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  • Answers to Your Common Oracle Database Lifecycle Management Questions

    - by Scott McNeil
    We recently ran a live webcast on Strategies for Managing Oracle Database's Lifecycle. There were tons of questions from our audience that we simply could not get to during the hour long presentation. Below are some of those questions along with their answers. Enjoy! Question: In the webcast the presenter talked about “gold” configuration standards, for those who want to use this technique, could you recommend a best practice to consider or follow? How do I get started? Answer:Gold configuration standardization is a quick and easy way to improve availability through consistency. Start by choosing a reference database and saving the configuration to the Oracle Enterprise Manager repository using the Save Configuration feature. Next create a comparison template using the Oracle provided template as a starting point and modify the ignored properties to eliminate expected differences in your environment. Finally create a comparison specification using the comparison template you created plus your saved gold configuration and schedule it to run on a regular basis. Don’t forget to fill in the email addresses of those you want to notify upon drift detection. Watch the database configuration management demo to learn more. Question: Can Oracle Lifecycle Management Pack for Database help with patching an Oracle Real Application Cluster (RAC) environment? Answer: Yes, Oracle Enterprise Manager supports both parallel and rolling patch application of Oracle Real Application Clusters. The use of rolling patching is recommended as there is no downtime involved. For more details watch this demo. Question: What are some of the things administrators can do to control configuration drift? Why is it important? Answer:Configuration drift is one of the main causes of instability and downtime of applications. Oracle Enterprise Manager makes it easy to manage and control drift using scheduled configuration comparisons combined with comparison templates. Question: Does Oracle Enterprise Manager 12c Release 2 offer an incremental update feature for "gold" images? For instance, if the source binary has a higher PSU level, what is the best approach to update the existing "gold" image in the software library? Do you have to create a new image or can you just update the original one? Answer:Provisioning Profiles (Gold images) can contain the installation files and database configuration templates. Although it is possible to make some changes to the profile after creation (mainly to configuration), it is normally recommended to simply create a new profile after applying a patch to your reference database. Question: The webcast talked about enforcing in-house standards, does Oracle Enterprise Manager 12c offer verification of your databases and systems to those standards? For example, the initial "gold" image has been massively deployed over time, and there may be some changes to it. How can you do regular checks from Enterprise Manager to ensure the in-house standards are being enforced? Answer:There are really two methods to validate conformity to standards. The first method is to use gold standards which you compare other databases to report unwanted differences. This method uses a new comparison template technology which allows users to ignore known differences (i.e. SID, Start time, etc) which results in a report only showing important or non-conformant differences. This method is quick to setup and configure and recommended for those who want to get started validating compliance quickly. The second method leverages the new compliance framework which allows the creation of specific and robust validations. These compliance rules are grouped into standards which can be assigned to databases quickly and easily. Compliance rules allow for targeted and more sophisticated validation beyond the basic equals operation available in the comparison method. The compliance framework can be used to implement just about any internal or industry standard. The compliance results will track current and historic compliance scores at the overall and individual database targets. When the issue is resolved, the score is automatically affected. Compliance framework is the recommended long term solution for validating compliance using Oracle Enterprise Manager 12c. Check out this demo on database compliance to learn more. Question: If you are using the integration between Oracle Enterprise Manager and My Oracle Support in an "offline" mode, how do you know if you have the latest My Oracle Support metadata? Answer:In Oracle Enterprise Manager 12c Release 2, you now only need to download one zip file containing all of the metadata xmls files. There is no indication that the metadata has changed but you could run a checksum on the file and compare it to the previously downloaded version to see if it has changed. Question: What happens if a patch fails while administrators are applying it to a database or system? Answer:A large portion of Oracle Enterprise Manager's patch automation is the pre-requisite checks that happen to ensure the highest level of confidence the patch will successfully apply. It is recommended you test the patch in a non-production environment and save the patch plan as a template once successful so you can create new plans using the saved template. If you are using the recommended ‘out of place’ patching methodology, there is no urgency because the database is still running as the cloned Oracle home is being patched. Users can address the issue and restart the patch procedure at the point it left off. If you are using 'in place' method, you can address the issue and continue where the procedure left off. Question: Can Oracle Enterprise Manager 12c R2 compare configurations between more than one target at the same time? Answer:Oracle Enterprise Manager 12c can compare any number of target configurations at one time. This is the basis of many important use cases including Configuration Drift Management. These comparisons can also be scheduled on a regular basis and emails notification sent should any differences appear. To learn more about configuration search and compare watch this demo. Question: How is data comparison done since changes are taking place in a live production system? Answer:There are many things to keep in mind when using the data comparison feature (as part of the Change Management ability to compare table data). It was primarily intended to be used for maintaining consistency of important but relatively static data. For example, application seed data and application setup configuration. This data does not change often but is critical when testing an application to ensure results are consistent with production. It is not recommended to use data comparison on highly dynamic data like transactional tables or very large tables. Question: Which versions of Oracle Database can be monitored through Oracle Enterprise Manager 12c? Answer:Oracle Database versions: 9.2.0.8, 10.1.0.5, 10.2.0.4, 10.2.0.5, 11.1.0.7, 11.2.0.1, 11.2.0.2, 11.2.0.3. Watch the On-Demand Webcast Stay Connected: Twitter | Facebook | YouTube | Linkedin | NewsletterDownload the Oracle Enterprise Manager Cloud Control12c Mobile app

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  • Consuming the Amazon S3 service from a Win8 Metro Application

    - by cibrax
    As many of the existing Http APIs for Cloud Services, AWS also provides a set of different platform SDKs for hiding many of complexities present in the APIs. While there is a platform SDK for .NET, which is open source and available in C#, that SDK does not work in Win8 Metro Applications for the changes introduced in WinRT. WinRT offers a complete different set of APIs for doing I/O operations such as doing http calls or using cryptography for signing or encrypting data, two aspects that are absolutely necessary for consuming AWS. All the I/O APIs available as part of WinRT are asynchronous, and uses the TPL model for .NET applications (HTML and JavaScript Metro applications use a model based in promises, which is similar concept).  In the case of S3, the http Authorization header is used for two purposes, authenticating clients and make sure the messages were not altered while they were in transit. For doing that, it uses a signature or hash of the message content and some of the headers using a symmetric key (That's just one of the available mechanisms). Windows Azure for example also uses the same mechanism in many of its APIs. There are three challenges that any developer working for first time in Metro will have to face to consume S3, the new WinRT APIs, the asynchronous nature of them and the complexity introduced for generating the Authorization header. Having said that, I decided to write this post with some of the gotchas I found myself trying to consume this Amazon service. 1. Generating the signature for the Authorization header All the cryptography APIs in WinRT are available under Windows.Security.Cryptography namespace. Many of operations available in these APIs uses the concept of buffers (IBuffer) for representing a chunk of binary data. As you will see in the example below, these buffers are mainly generated with the use of static methods in a WinRT class CryptographicBuffer available as part of the namespace previously mentioned. private string DeriveAuthToken(string resource, string httpMethod, string timestamp) { var stringToSign = string.Format("{0}\n" + "\n" + "\n" + "\n" + "x-amz-date:{1}\n" + "/{2}/", httpMethod, timestamp, resource); var algorithm = MacAlgorithmProvider.OpenAlgorithm("HMAC_SHA1"); var keyMaterial = CryptographicBuffer.CreateFromByteArray(Encoding.UTF8.GetBytes(this.secret)); var hmacKey = algorithm.CreateKey(keyMaterial); var signature = CryptographicEngine.Sign( hmacKey, CryptographicBuffer.CreateFromByteArray(Encoding.UTF8.GetBytes(stringToSign)) ); return CryptographicBuffer.EncodeToBase64String(signature); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The algorithm that determines the information or content you need to use for generating the signature is very well described as part of the AWS documentation. In this case, this method is generating a signature required for creating a new bucket. A HmacSha1 hash is computed using a secret or symetric key provided by AWS in the management console. 2. Sending an Http Request to the S3 service WinRT also ships with the System.Net.Http.HttpClient that was first introduced some months ago with ASP.NET Web API. This client provides a rich interface on top the traditional WebHttpRequest class, and also solves some of limitations found in this last one. There are a few things that don't work with a raw WebHttpRequest such as setting the Host header, which is something absolutely required for consuming S3. Also, HttpClient is more friendly for doing unit tests, as it receives a HttpMessageHandler as part of the constructor that can fake to emulate a real http call. This is how the code for consuming the service with HttpClient looks like, public async Task<S3Response> CreateBucket(string name, string region = null, params string[] acl) { var timestamp = string.Format("{0:r}", DateTime.UtcNow); var auth = DeriveAuthToken(name, "PUT", timestamp); var request = new HttpRequestMessage(HttpMethod.Put, "http://s3.amazonaws.com/"); request.Headers.Host = string.Format("{0}.s3.amazonaws.com", name); request.Headers.TryAddWithoutValidation("Authorization", "AWS " + this.key + ":" + auth); request.Headers.Add("x-amz-date", timestamp); var client = new HttpClient(); var response = await client.SendAsync(request); return new S3Response { Succeed = response.StatusCode == HttpStatusCode.OK, Message = (response.Content != null) ? await response.Content.ReadAsStringAsync() : null }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You will notice a few additional things in this code. By default, HttpClient validates the values for some well-know headers, and Authorization is one of them. It won't allow you to set a value with ":" on it, which is something that S3 expects. However, that's not a problem at all, as you can skip the validation by using the TryAddWithoutValidation method. Also, the code is heavily relying on the new async and await keywords to transform all the asynchronous calls into synchronous ones. In case you would want to unit test this code and faking the call to the real S3 service, you should have to modify it to inject a custom HttpMessageHandler into the HttpClient. The following implementation illustrates this concept, In case you would want to unit test this code and faking the call to the real S3 service, you should have to modify it to inject a custom HttpMessageHandler into the HttpClient. The following implementation illustrates this concept, public class FakeHttpMessageHandler : HttpMessageHandler { HttpResponseMessage response; public FakeHttpMessageHandler(HttpResponseMessage response) { this.response = response; } protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) { var tcs = new TaskCompletionSource<HttpResponseMessage>(); tcs.SetResult(response); return tcs.Task; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You can use this handler for injecting any response while you are unit testing the code.

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  • Consuming the Amazon S3 service from a Win8 Metro Application

    - by cibrax
    As many of the existing Http APIs for Cloud Services, AWS also provides a set of different platform SDKs for hiding many of complexities present in the APIs. While there is a platform SDK for .NET, which is open source and available in C#, that SDK does not work in Win8 Metro Applications for the changes introduced in WinRT. WinRT offers a complete different set of APIs for doing I/O operations such as doing http calls or using cryptography for signing or encrypting data, two aspects that are absolutely necessary for consuming AWS. All the I/O APIs available as part of WinRT are asynchronous, and uses the TPL model for .NET applications (HTML and JavaScript Metro applications use a model based in promises, which is similar concept).  In the case of S3, the http Authorization header is used for two purposes, authenticating clients and make sure the messages were not altered while they were in transit. For doing that, it uses a signature or hash of the message content and some of the headers using a symmetric key (That's just one of the available mechanisms). Windows Azure for example also uses the same mechanism in many of its APIs. There are three challenges that any developer working for first time in Metro will have to face to consume S3, the new WinRT APIs, the asynchronous nature of them and the complexity introduced for generating the Authorization header. Having said that, I decided to write this post with some of the gotchas I found myself trying to consume this Amazon service. 1. Generating the signature for the Authorization header All the cryptography APIs in WinRT are available under Windows.Security.Cryptography namespace. Many of operations available in these APIs uses the concept of buffers (IBuffer) for representing a chunk of binary data. As you will see in the example below, these buffers are mainly generated with the use of static methods in a WinRT class CryptographicBuffer available as part of the namespace previously mentioned. private string DeriveAuthToken(string resource, string httpMethod, string timestamp) { var stringToSign = string.Format("{0}\n" + "\n" + "\n" + "\n" + "x-amz-date:{1}\n" + "/{2}/", httpMethod, timestamp, resource); var algorithm = MacAlgorithmProvider.OpenAlgorithm("HMAC_SHA1"); var keyMaterial = CryptographicBuffer.CreateFromByteArray(Encoding.UTF8.GetBytes(this.secret)); var hmacKey = algorithm.CreateKey(keyMaterial); var signature = CryptographicEngine.Sign( hmacKey, CryptographicBuffer.CreateFromByteArray(Encoding.UTF8.GetBytes(stringToSign)) ); return CryptographicBuffer.EncodeToBase64String(signature); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The algorithm that determines the information or content you need to use for generating the signature is very well described as part of the AWS documentation. In this case, this method is generating a signature required for creating a new bucket. A HmacSha1 hash is computed using a secret or symetric key provided by AWS in the management console. 2. Sending an Http Request to the S3 service WinRT also ships with the System.Net.Http.HttpClient that was first introduced some months ago with ASP.NET Web API. This client provides a rich interface on top the traditional WebHttpRequest class, and also solves some of limitations found in this last one. There are a few things that don't work with a raw WebHttpRequest such as setting the Host header, which is something absolutely required for consuming S3. Also, HttpClient is more friendly for doing unit tests, as it receives a HttpMessageHandler as part of the constructor that can fake to emulate a real http call. This is how the code for consuming the service with HttpClient looks like, public async Task<S3Response> CreateBucket(string name, string region = null, params string[] acl) { var timestamp = string.Format("{0:r}", DateTime.UtcNow); var auth = DeriveAuthToken(name, "PUT", timestamp); var request = new HttpRequestMessage(HttpMethod.Put, "http://s3.amazonaws.com/"); request.Headers.Host = string.Format("{0}.s3.amazonaws.com", name); request.Headers.TryAddWithoutValidation("Authorization", "AWS " + this.key + ":" + auth); request.Headers.Add("x-amz-date", timestamp); var client = new HttpClient(); var response = await client.SendAsync(request); return new S3Response { Succeed = response.StatusCode == HttpStatusCode.OK, Message = (response.Content != null) ? await response.Content.ReadAsStringAsync() : null }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You will notice a few additional things in this code. By default, HttpClient validates the values for some well-know headers, and Authorization is one of them. It won't allow you to set a value with ":" on it, which is something that S3 expects. However, that's not a problem at all, as you can skip the validation by using the TryAddWithoutValidation method. Also, the code is heavily relying on the new async and await keywords to transform all the asynchronous calls into synchronous ones. In case you would want to unit test this code and faking the call to the real S3 service, you should have to modify it to inject a custom HttpMessageHandler into the HttpClient. The following implementation illustrates this concept, In case you would want to unit test this code and faking the call to the real S3 service, you should have to modify it to inject a custom HttpMessageHandler into the HttpClient. The following implementation illustrates this concept, public class FakeHttpMessageHandler : HttpMessageHandler { HttpResponseMessage response; public FakeHttpMessageHandler(HttpResponseMessage response) { this.response = response; } protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) { var tcs = new TaskCompletionSource<HttpResponseMessage>(); tcs.SetResult(response); return tcs.Task; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You can use this handler for injecting any response while you are unit testing the code.

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  • The Great Divorce

    - by BlackRabbitCoder
    I have a confession to make: I've been in an abusive relationship for more than 17 years now.  Yes, I am not ashamed to admit it, but I'm finally doing something about it. I met her in college, she was new and sexy and amazingly fast -- and I'd never met anything like her before.  Her style and her power captivated me and I couldn't wait to learn more about her.  I took a chance on her, and though I learned a lot from her -- and will always be grateful for my time with her -- I think it's time to move on. Her name was C++, and she so outshone my previous love, C, that any thoughts of going back evaporated in the heat of this new romance.  She promised me she'd be gentle and not hurt me the way C did.  She promised me she'd clean-up after herself better than C did.  She promised me she'd be less enigmatic and easier to keep happy than C was.  But I was deceived.  Oh sure, as far as truth goes, it wasn't a complete lie.  To some extent she was more fun, more powerful, safer, and easier to maintain.  But it just wasn't good enough -- or at least it's not good enough now. I loved C++, some part of me still does, it's my first-love of programming languages and I recognize its raw power, its blazing speed, and its improvements over its predecessor.  But with today's hardware, at speeds we could only dream to conceive of twenty years ago, that need for speed -- at the cost of all else -- has died, and that has left my feelings for C++ moribund. If I ever need to write an operating system or a device driver, then I might need that speed.  But 99% of the time I don't.  I'm a business-type programmer and chances are 90% of you are too, and even the ones who need speed at all costs may be surprised by how much you sacrifice for that.   That's not to say that I don't want my software to perform, and it's not to say that in the business world we don't care about speed or that our job is somehow less difficult or technical.  There's many times we write programs to handle millions of real-time updates or handle thousands of financial transactions or tracking trading algorithms where every second counts.  But if I choose to write my code in C++ purely for speed chances are I'll never notice the speed increase -- and equally true chances are it will be far more prone to crash and far less easy to maintain.  Nearly without fail, it's the macro-optimizations you need, not the micro-optimizations.  If I choose to write a O(n2) algorithm when I could have used a O(n) algorithm -- that can kill me.  If I choose to go to the database to load a piece of unchanging data every time instead of caching it on first load -- that too can kill me.  And if I cross the network multiple times for pieces of data instead of getting it all at once -- yes that can also kill me.  But choosing an overly powerful and dangerous mid-level language to squeeze out every last drop of performance will realistically not make stock orders process any faster, and more likely than not open up the system to more risk of crashes and resource leaks. And that's when my love for C++ began to die.  When I noticed that I didn't need that speed anymore.  That that speed was really kind of a lie.  Sure, I can be super efficient and pack bits in a byte instead of using separate boolean values.  Sure, I can use an unsigned char instead of an int.  But in the grand scheme of things it doesn't matter as much as you think it does.  The key is maintainability, and that's where C++ failed me.  I like to tell the other developers I work with that there's two levels of correctness in coding: Is it immediately correct? Will it stay correct? That is, you can hack together any piece of code and make it correct to satisfy a task at hand, but if a new developer can't come in tomorrow and make a fairly significant change to it without jeopardizing that correctness, it won't stay correct. Some people laugh at me when I say I now prefer maintainability over speed.  But that is exactly the point.  If you focus solely on speed you tend to produce code that is much harder to maintain over the long hall, and that's a load of technical debt most shops can't afford to carry and end up completely scrapping code before it's time.  When good code is written well for maintainability, though, it can be correct both now and in the future. And you know the best part is?  My new love is nearly as fast as C++, and in some cases even faster -- and better than that, I know C# will treat me right.  Her creators have poured hundreds of thousands of hours of time into making her the sexy beast she is today.  They made her easy to understand and not an enigmatic mess.  They made her consistent and not moody and amorphous.  And they made her perform as fast as I care to go by optimizing her both at compile time and a run-time. Her code is so elegant and easy on the eyes that I'm not worried where she will run to or what she'll pull behind my back.  She is powerful enough to handle all my tasks, fast enough to execute them with blazing speed, maintainable enough so that I can rely on even fairly new peers to modify my work, and rich enough to allow me to satisfy any need.  C# doesn't ask me to clean up her messes!  She cleans up after herself and she tries to make my life easier for me by taking on most of those optimization tasks C++ asked me to take upon myself.  Now, there are many of you who would say that I am the cause of my own grief, that it was my fault C++ didn't behave because I didn't pay enough attention to her.  That I alone caused the pain she inflicted on me.  And to some extent, you have a point.  But she was so high maintenance, requiring me to know every twist and turn of her vast and unrestrained power that any wrong term or bout of forgetfulness was met with painful reminders that she wasn't going to watch my back when I made a mistake.  But C#, she loves me when I'm good, and she loves me when I'm bad, and together we make beautiful code that is both fast and safe. So that's why I'm leaving C++ behind.  She says she's changing for me, but I have no interest in what C++0x may bring.  Oh, I'll still keep in touch, and maybe I'll see her now and again when she brings her problems to my door and asks for some attention -- for I always have a soft spot for her, you see.  But she's out of my house now.  I have three kids and a dog and a cat, and all require me to clean up after them, why should I have to clean up after my programming language as well?

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  • C#/.NET Little Wonders: Comparer&lt;T&gt;.Default

    - by James Michael Hare
    I’ve been working with a wonderful team on a major release where I work, which has had the side-effect of occupying most of my spare time preparing, testing, and monitoring.  However, I do have this Little Wonder tidbit to offer today. Introduction The IComparable<T> interface is great for implementing a natural order for a data type.  It’s a very simple interface with a single method: 1: public interface IComparer<in T> 2: { 3: // Compare two instances of same type. 4: int Compare(T x, T y); 5: }  So what do we expect for the integer return value?  It’s a pseudo-relative measure of the ordering of x and y, which returns an integer value in much the same way C++ returns an integer result from the strcmp() c-style string comparison function: If x == y, returns 0. If x > y, returns > 0 (often +1, but not guaranteed) If x < y, returns < 0 (often –1, but not guaranteed) Notice that the comparison operator used to evaluate against zero should be the same comparison operator you’d use as the comparison operator between x and y.  That is, if you want to see if x > y you’d see if the result > 0. The Problem: Comparing With null Can Be Messy This gets tricky though when you have null arguments.  According to the MSDN, a null value should be considered equal to a null value, and a null value should be less than a non-null value.  So taking this into account we’d expect this instead: If x == y (or both null), return 0. If x > y (or y only is null), return > 0. If x < y (or x only is null), return < 0. But here’s the problem – if x is null, what happens when we attempt to call CompareTo() off of x? 1: // what happens if x is null? 2: x.CompareTo(y); It’s pretty obvious we’ll get a NullReferenceException here.  Now, we could guard against this before calling CompareTo(): 1: int result; 2:  3: // first check to see if lhs is null. 4: if (x == null) 5: { 6: // if lhs null, check rhs to decide on return value. 7: if (y == null) 8: { 9: result = 0; 10: } 11: else 12: { 13: result = -1; 14: } 15: } 16: else 17: { 18: // CompareTo() should handle a null y correctly and return > 0 if so. 19: result = x.CompareTo(y); 20: } Of course, we could shorten this with the ternary operator (?:), but even then it’s ugly repetitive code: 1: int result = (x == null) 2: ? ((y == null) ? 0 : -1) 3: : x.CompareTo(y); Fortunately, the null issues can be cleaned up by drafting in an external Comparer.  The Soltuion: Comparer<T>.Default You can always develop your own instance of IComparer<T> for the job of comparing two items of the same type.  The nice thing about a IComparer is its is independent of the things you are comparing, so this makes it great for comparing in an alternative order to the natural order of items, or when one or both of the items may be null. 1: public class NullableIntComparer : IComparer<int?> 2: { 3: public int Compare(int? x, int? y) 4: { 5: return (x == null) 6: ? ((y == null) ? 0 : -1) 7: : x.Value.CompareTo(y); 8: } 9: }  Now, if you want a custom sort -- especially on large-grained objects with different possible sort fields -- this is the best option you have.  But if you just want to take advantage of the natural ordering of the type, there is an easier way.  If the type you want to compare already implements IComparable<T> or if the type is System.Nullable<T> where T implements IComparable, there is a class in the System.Collections.Generic namespace called Comparer<T> which exposes a property called Default that will create a singleton that represents the default comparer for items of that type.  For example: 1: // compares integers 2: var intComparer = Comparer<int>.Default; 3:  4: // compares DateTime values 5: var dateTimeComparer = Comparer<DateTime>.Default; 6:  7: // compares nullable doubles using the null rules! 8: var nullableDoubleComparer = Comparer<double?>.Default;  This helps you avoid having to remember the messy null logic and makes it to compare objects where you don’t know if one or more of the values is null. This works especially well when creating say an IComparer<T> implementation for a large-grained class that may or may not contain a field.  For example, let’s say you want to create a sorting comparer for a stock open price, but if the market the stock is trading in hasn’t opened yet, the open price will be null.  We could handle this (assuming a reasonable Quote definition) like: 1: public class Quote 2: { 3: // the opening price of the symbol quoted 4: public double? Open { get; set; } 5:  6: // ticker symbol 7: public string Symbol { get; set; } 8:  9: // etc. 10: } 11:  12: public class OpenPriceQuoteComparer : IComparer<Quote> 13: { 14: // Compares two quotes by opening price 15: public int Compare(Quote x, Quote y) 16: { 17: return Comparer<double?>.Default.Compare(x.Open, y.Open); 18: } 19: } Summary Defining a custom comparer is often needed for non-natural ordering or defining alternative orderings, but when you just want to compare two items that are IComparable<T> and account for null behavior, you can use the Comparer<T>.Default comparer generator and you’ll never have to worry about correct null value sorting again.     Technorati Tags: C#,.NET,Little Wonders,BlackRabbitCoder,IComparable,Comparer

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  • CodePlex Daily Summary for Monday, June 02, 2014

    CodePlex Daily Summary for Monday, June 02, 2014Popular ReleasesPortable Class Library for SQLite: Portable Class Library for SQLite - 3.8.4.4: This pull request from mattleibow addresses an issue with custom function creation (define functions in C# code and invoke them from SQLite as id they where regular SQL functions). Impact: Xamarin iOSTweetinvi a friendly Twitter C# API: Tweetinvi 0.9.3.x: Timelines- Added all the parameters available from the Timeline Endpoints in Tweetinvi. - This is available for HomeTimeline, UserTimeline, MentionsTimeline // Simple query var tweets = Timeline.GetHomeTimeline(); // Create a parameter for queries with specific parameters var timelineParameter = Timeline.GenerateHomeTimelineRequestParameter(); timelineParameter.ExcludeReplies = true; timelineParameter.TrimUser = true; var tweets = Timeline.GetHomeTimeline(timelineParameter); Tweets- Add mis...Sandcastle Help File Builder: Help File Builder and Tools v2014.5.31.0: General InformationIMPORTANT: On some systems, the content of the ZIP file is blocked and the installer may fail to run. Before extracting it, right click on the ZIP file, select Properties, and click on the Unblock button if it is present in the lower right corner of the General tab in the properties dialog. This release completes removal of the branding transformations and implements the new VS2013 presentation style that utilizes the new lightweight website format. Several breaking cha...Tooltip Web Preview: ToolTip Web Preview: Version 1.0Database Helper: Release 1.0.0.0: First Release of Database HelperCoMaSy: CoMaSy1.0.2: !Contact Management SystemImage View Slider: Image View Slider: This is a .NET component. We create this using VB.NET. Here you can use an Image Viewer with several properties to your application form. We wish somebody to improve freely. Try this out! Author : Steven Renaldo Antony Yustinus Arjuna Purnama Putra Andre Wijaya P Martin Lidau PBK GENAP 2014 - TI UKDWAspose for Apache POI: Missing Features of Apache POI WP - v 1.1: Release contain the Missing Features in Apache POI WP SDK in Comparison with Aspose.Words for dealing with Microsoft Word. What's New ?Following Examples: Insert Picture in Word Document Insert Comments Set Page Borders Mail Merge from XML Data Source Moving the Cursor Feedback and Suggestions Many more examples are yet to come here. Keep visiting us. Raise your queries and suggest more examples via Aspose Forums or via this social coding site.SEToolbox: 01.032.014 Release 1: Added fix when loading game Textures for icons causing 'Unable to read beyond the end of the stream'. Added new Resource Report, that displays all in game resources in a concise report. Added in temp directory cleaner, to keep excess files from building up. Fixed use of colors on the windows, to work better with desktop schemes. Adding base support for multilingual resources. This will allow loading of the Space Engineers resources to show localized names, and display localized date a...ClosedXML - The easy way to OpenXML: ClosedXML 0.71.2: More memory and performance improvements. Fixed an issue with pivot table field order.Vi-AIO SearchBar: Vi – AIO Search Bar: Version 1.0Top Verses ( Ayat Emas ): Binary Top Verses: This one is the bin folder of the component. the .dll component is inside.Traditional Calendar Component: Traditional Calender Converter: Duta Wacana Christian University This file containing Traditional Calendar Component and Demo Aplication that using Traditional Calendar Component. This component made with .NET Framework 4 and the programming language is C# .SQLSetupHelper: 1.0.0.0: First Stable Version of SQL SetupComposite Iconote: Composite Iconote: This is a composite has been made by Microsoft Visual Studio 2013. Requirement: To develop this composite or use this component in your application, your computer must have .NET framework 4.5 or newer.Magick.NET: Magick.NET 6.8.9.101: Magick.NET linked with ImageMagick 6.8.9.1. Breaking changes: - Int/short Set methods of WritablePixelCollection are now unsigned. - The Q16 build no longer uses HDRI, switch to the new Q16-HDRI build if you need HDRI.fnr.exe - Find And Replace Tool: 1.7: Bug fixes Refactored logic for encoding text values to command line to handle common edge cases where find/replace operation works in GUI but not in command line Fix for bug where selection in Encoding drop down was different when generating command line in some cases. It was reported in: https://findandreplace.codeplex.com/workitem/34 Fix for "Backslash inserted before dot in replacement text" reported here: https://findandreplace.codeplex.com/discussions/541024 Fix for finding replacing...VG-Ripper & PG-Ripper: VG-Ripper 2.9.59: changes NEW: Added Support for 'GokoImage.com' links NEW: Added Support for 'ViperII.com' links NEW: Added Support for 'PixxxView.com' links NEW: Added Support for 'ImgRex.com' links NEW: Added Support for 'PixLiv.com' links NEW: Added Support for 'imgsee.me' links NEW: Added Support for 'ImgS.it' linksToolbox for Dynamics CRM 2011/2013: XrmToolBox (v1.2014.5.28): XrmToolbox improvement XrmToolBox updates (v1.2014.5.28)Fix connecting to a connection with custom authentication without saved password Tools improvement New tool!Solution Components Mover (v1.2014.5.22) Transfer solution components from one solution to another one Import/Export NN relationships (v1.2014.3.7) Allows you to import and export many to many relationships Tools updatesAttribute Bulk Updater (v1.2014.5.28) Audit Center (v1.2014.5.28) View Layout Replicator (v1.2014.5.28) Scrip...Microsoft Ajax Minifier: Microsoft Ajax Minifier 5.10: Fix for Issue #20875 - echo switch doesn't work for CSS CSS should honor the SASS source-file comments JS should allow multi-line comment directivesNew Projects[ISEN] Rendu de projet Naughty3Dogs - Pong3D: Pong3D est un jeu qui reprend le principe classique du Pong en le portant dans un environnement 3D à l'aide du langage c# et du moteur Unity3DBootstrap for MVC: Bootstrap for MVC.F. A. Q. - Najczesciej zadawane pytania: FAQForuMvc: Technifutur short projecthomework456: no.iStoody: Studies organize solution, available through app for Windows and Windows Phone.liaoliao: ???????????Price Tracker: Allows a user to track prices based on parsed emailsRoslynEval: RoslynRx Hub: Rx Hub provides server side computation which initiate by subscriber requestSharepoint Online AppCache Reset: We are an IT resource company providing Virtual IT services and custom and opensource programs for everyday needs. UnitConversionLib : Smart Unit Conversion Library in C#: Conversion of units, arithmetic operation and parsing quantities with their units on run time. Smart unit converter and conversion lib for physical quantities,

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  • Inheritance Mapping Strategies with Entity Framework Code First CTP5: Part 2 – Table per Type (TPT)

    - by mortezam
    In the previous blog post you saw that there are three different approaches to representing an inheritance hierarchy and I explained Table per Hierarchy (TPH) as the default mapping strategy in EF Code First. We argued that the disadvantages of TPH may be too serious for our design since it results in denormalized schemas that can become a major burden in the long run. In today’s blog post we are going to learn about Table per Type (TPT) as another inheritance mapping strategy and we'll see that TPT doesn’t expose us to this problem. Table per Type (TPT)Table per Type is about representing inheritance relationships as relational foreign key associations. Every class/subclass that declares persistent properties—including abstract classes—has its own table. The table for subclasses contains columns only for each noninherited property (each property declared by the subclass itself) along with a primary key that is also a foreign key of the base class table. This approach is shown in the following figure: For example, if an instance of the CreditCard subclass is made persistent, the values of properties declared by the BillingDetail base class are persisted to a new row of the BillingDetails table. Only the values of properties declared by the subclass (i.e. CreditCard) are persisted to a new row of the CreditCards table. The two rows are linked together by their shared primary key value. Later, the subclass instance may be retrieved from the database by joining the subclass table with the base class table. TPT Advantages The primary advantage of this strategy is that the SQL schema is normalized. In addition, schema evolution is straightforward (modifying the base class or adding a new subclass is just a matter of modify/add one table). Integrity constraint definition are also straightforward (note how CardType in CreditCards table is now a non-nullable column). Another much more important advantage is the ability to handle polymorphic associations (a polymorphic association is an association to a base class, hence to all classes in the hierarchy with dynamic resolution of the concrete class at runtime). A polymorphic association to a particular subclass may be represented as a foreign key referencing the table of that particular subclass. Implement TPT in EF Code First We can create a TPT mapping simply by placing Table attribute on the subclasses to specify the mapped table name (Table attribute is a new data annotation and has been added to System.ComponentModel.DataAnnotations namespace in CTP5): public abstract class BillingDetail {     public int BillingDetailId { get; set; }     public string Owner { get; set; }     public string Number { get; set; } } [Table("BankAccounts")] public class BankAccount : BillingDetail {     public string BankName { get; set; }     public string Swift { get; set; } } [Table("CreditCards")] public class CreditCard : BillingDetail {     public int CardType { get; set; }     public string ExpiryMonth { get; set; }     public string ExpiryYear { get; set; } } public class InheritanceMappingContext : DbContext {     public DbSet<BillingDetail> BillingDetails { get; set; } } If you prefer fluent API, then you can create a TPT mapping by using ToTable() method: protected override void OnModelCreating(ModelBuilder modelBuilder) {     modelBuilder.Entity<BankAccount>().ToTable("BankAccounts");     modelBuilder.Entity<CreditCard>().ToTable("CreditCards"); } Generated SQL For QueriesLet’s take an example of a simple non-polymorphic query that returns a list of all the BankAccounts: var query = from b in context.BillingDetails.OfType<BankAccount>() select b; Executing this query (by invoking ToList() method) results in the following SQL statements being sent to the database (on the bottom, you can also see the result of executing the generated query in SQL Server Management Studio): Now, let’s take an example of a very simple polymorphic query that requests all the BillingDetails which includes both BankAccount and CreditCard types: projects some properties out of the base class BillingDetail, without querying for anything from any of the subclasses: var query = from b in context.BillingDetails             select new { b.BillingDetailId, b.Number, b.Owner }; -- var query = from b in context.BillingDetails select b; This LINQ query seems even more simple than the previous one but the resulting SQL query is not as simple as you might expect: -- As you can see, EF Code First relies on an INNER JOIN to detect the existence (or absence) of rows in the subclass tables CreditCards and BankAccounts so it can determine the concrete subclass for a particular row of the BillingDetails table. Also the SQL CASE statements that you see in the beginning of the query is just to ensure columns that are irrelevant for a particular row have NULL values in the returning flattened table. (e.g. BankName for a row that represents a CreditCard type) TPT ConsiderationsEven though this mapping strategy is deceptively simple, the experience shows that performance can be unacceptable for complex class hierarchies because queries always require a join across many tables. In addition, this mapping strategy is more difficult to implement by hand— even ad-hoc reporting is more complex. This is an important consideration if you plan to use handwritten SQL in your application (For ad hoc reporting, database views provide a way to offset the complexity of the TPT strategy. A view may be used to transform the table-per-type model into the much simpler table-per-hierarchy model.) SummaryIn this post we learned about Table per Type as the second inheritance mapping in our series. So far, the strategies we’ve discussed require extra consideration with regard to the SQL schema (e.g. in TPT, foreign keys are needed). This situation changes with the Table per Concrete Type (TPC) that we will discuss in the next post. References ADO.NET team blog Java Persistence with Hibernate book a { text-decoration: none; } a:visited { color: Blue; } .title { padding-bottom: 5px; font-family: Segoe UI; font-size: 11pt; font-weight: bold; padding-top: 15px; } .code, .typeName { font-family: consolas; } .typeName { color: #2b91af; } .padTop5 { padding-top: 5px; } .padTop10 { padding-top: 10px; } p.MsoNormal { margin-top: 0in; margin-right: 0in; margin-bottom: 10.0pt; margin-left: 0in; line-height: 115%; font-size: 11.0pt; font-family: "Calibri" , "sans-serif"; }

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  • I see no LOBs!

    - by Paul White
    Is it possible to see LOB (large object) logical reads from STATISTICS IO output on a table with no LOB columns? I was asked this question today by someone who had spent a good fraction of their afternoon trying to work out why this was occurring – even going so far as to re-run DBCC CHECKDB to see if any corruption had taken place.  The table in question wasn’t particularly pretty – it had grown somewhat organically over time, with new columns being added every so often as the need arose.  Nevertheless, it remained a simple structure with no LOB columns – no TEXT or IMAGE, no XML, no MAX types – nothing aside from ordinary INT, MONEY, VARCHAR, and DATETIME types.  To add to the air of mystery, not every query that ran against the table would report LOB logical reads – just sometimes – but when it did, the query often took much longer to execute. Ok, enough of the pre-amble.  I can’t reproduce the exact structure here, but the following script creates a table that will serve to demonstrate the effect: IF OBJECT_ID(N'dbo.Test', N'U') IS NOT NULL DROP TABLE dbo.Test GO CREATE TABLE dbo.Test ( row_id NUMERIC IDENTITY NOT NULL,   col01 NVARCHAR(450) NOT NULL, col02 NVARCHAR(450) NOT NULL, col03 NVARCHAR(450) NOT NULL, col04 NVARCHAR(450) NOT NULL, col05 NVARCHAR(450) NOT NULL, col06 NVARCHAR(450) NOT NULL, col07 NVARCHAR(450) NOT NULL, col08 NVARCHAR(450) NOT NULL, col09 NVARCHAR(450) NOT NULL, col10 NVARCHAR(450) NOT NULL, CONSTRAINT [PK dbo.Test row_id] PRIMARY KEY CLUSTERED (row_id) ) ; The next script loads the ten variable-length character columns with one-character strings in the first row, two-character strings in the second row, and so on down to the 450th row: WITH Numbers AS ( -- Generates numbers 1 - 450 inclusive SELECT TOP (450) n = ROW_NUMBER() OVER (ORDER BY (SELECT 0)) FROM master.sys.columns C1, master.sys.columns C2, master.sys.columns C3 ORDER BY n ASC ) INSERT dbo.Test WITH (TABLOCKX) SELECT REPLICATE(N'A', N.n), REPLICATE(N'B', N.n), REPLICATE(N'C', N.n), REPLICATE(N'D', N.n), REPLICATE(N'E', N.n), REPLICATE(N'F', N.n), REPLICATE(N'G', N.n), REPLICATE(N'H', N.n), REPLICATE(N'I', N.n), REPLICATE(N'J', N.n) FROM Numbers AS N ORDER BY N.n ASC ; Once those two scripts have run, the table contains 450 rows and 10 columns of data like this: Most of the time, when we query data from this table, we don’t see any LOB logical reads, for example: -- Find the maximum length of the data in -- column 5 for a range of rows SELECT result = MAX(DATALENGTH(T.col05)) FROM dbo.Test AS T WHERE row_id BETWEEN 50 AND 100 ; But with a different query… -- Read all the data in column 1 SELECT result = MAX(DATALENGTH(T.col01)) FROM dbo.Test AS T ; …suddenly we have 49 LOB logical reads, as well as the ‘normal’ logical reads we would expect. The Explanation If we had tried to create this table in SQL Server 2000, we would have received a warning message to say that future INSERT or UPDATE operations on the table might fail if the resulting row exceeded the in-row storage limit of 8060 bytes.  If we needed to store more data than would fit in an 8060 byte row (including internal overhead) we had to use a LOB column – TEXT, NTEXT, or IMAGE.  These special data types store the large data values in a separate structure, with just a small pointer left in the original row. Row Overflow SQL Server 2005 introduced a feature called row overflow, which allows one or more variable-length columns in a row to move to off-row storage if the data in a particular row would otherwise exceed 8060 bytes.  You no longer receive a warning when creating (or altering) a table that might need more than 8060 bytes of in-row storage; if SQL Server finds that it can no longer fit a variable-length column in a particular row, it will silently move one or more of these columns off the row into a separate allocation unit. Only variable-length columns can be moved in this way (for example the (N)VARCHAR, VARBINARY, and SQL_VARIANT types).  Fixed-length columns (like INTEGER and DATETIME for example) never move into ‘row overflow’ storage.  The decision to move a column off-row is done on a row-by-row basis – so data in a particular column might be stored in-row for some table records, and off-row for others. In general, if SQL Server finds that it needs to move a column into row-overflow storage, it moves the largest variable-length column record for that row.  Note that in the case of an UPDATE statement that results in the 8060 byte limit being exceeded, it might not be the column that grew that is moved! Sneaky LOBs Anyway, that’s all very interesting but I don’t want to get too carried away with the intricacies of row-overflow storage internals.  The point is that it is now possible to define a table with non-LOB columns that will silently exceed the old row-size limit and result in ordinary variable-length columns being moved to off-row storage.  Adding new columns to a table, expanding an existing column definition, or simply storing more data in a column than you used to – all these things can result in one or more variable-length columns being moved off the row. Note that row-overflow storage is logically quite different from old-style LOB and new-style MAX data type storage – individual variable-length columns are still limited to 8000 bytes each – you can just have more of them now.  Having said that, the physical mechanisms involved are very similar to full LOB storage – a column moved to row-overflow leaves a 24-byte pointer record in the row, and the ‘separate storage’ I have been talking about is structured very similarly to both old-style LOBs and new-style MAX types.  The disadvantages are also the same: when SQL Server needs a row-overflow column value it needs to follow the in-row pointer a navigate another chain of pages, just like retrieving a traditional LOB. And Finally… In the example script presented above, the rows with row_id values from 402 to 450 inclusive all exceed the total in-row storage limit of 8060 bytes.  A SELECT that references a column in one of those rows that has moved to off-row storage will incur one or more lob logical reads as the storage engine locates the data.  The results on your system might vary slightly depending on your settings, of course; but in my tests only column 1 in rows 402-450 moved off-row.  You might like to play around with the script – updating columns, changing data type lengths, and so on – to see the effect on lob logical reads and which columns get moved when.  You might even see row-overflow columns moving back in-row if they are updated to be smaller (hint: reduce the size of a column entry by at least 1000 bytes if you hope to see this). Be aware that SQL Server will not warn you when it moves ‘ordinary’ variable-length columns into overflow storage, and it can have dramatic effects on performance.  It makes more sense than ever to choose column data types sensibly.  If you make every column a VARCHAR(8000) or NVARCHAR(4000), and someone stores data that results in a row needing more than 8060 bytes, SQL Server might turn some of your column data into pseudo-LOBs – all without saying a word. Finally, some people make a distinction between ordinary LOBs (those that can hold up to 2GB of data) and the LOB-like structures created by row-overflow (where columns are still limited to 8000 bytes) by referring to row-overflow LOBs as SLOBs.  I find that quite appealing, but the ‘S’ stands for ‘small’, which makes expanding the whole acronym a little daft-sounding…small large objects anyone? © Paul White 2011 email: [email protected] twitter: @SQL_Kiwi

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  • How do I restrict concurrent statistics gathering to a small set of tables from a single schema?

    - by Maria Colgan
    I got an interesting question from one of my colleagues in the performance team last week about how to restrict a concurrent statistics gather to a small subset of tables from one schema, rather than the entire schema. I thought I would share the solution we came up with because it was rather elegant, and took advantage of concurrent statistics gathering, incremental statistics, and the not so well known “obj_filter_list” parameter in DBMS_STATS.GATHER_SCHEMA_STATS procedure. You should note that the solution outline below with “obj_filter_list” still applies, even when concurrent statistics gathering and/or incremental statistics gathering is disabled. The reason my colleague had asked the question in the first place was because he wanted to enable incremental statistics for 5 large partitioned tables in one schema. The first time you gather statistics after you enable incremental statistics on a table, you have to gather statistics for all of the existing partitions so that a synopsis may be created for them. If the partitioned table in question is large and contains a lot of partition, this could take a considerable amount of time. Since my colleague only had the Exadata environment at his disposal overnight, he wanted to re-gather statistics on 5 partition tables as quickly as possible to ensure that it all finished before morning. Prior to Oracle Database 11g Release 2, the only way to do this would have been to write a script with an individual DBMS_STATS.GATHER_TABLE_STATS command for each partition, in each of the 5 tables, as well as another one to gather global statistics on the table. Then, run each script in a separate session and manually manage how many of this session could run concurrently. Since each table has over one thousand partitions that would definitely be a daunting task and would most likely keep my colleague up all night! In Oracle Database 11g Release 2 we can take advantage of concurrent statistics gathering, which enables us to gather statistics on multiple tables in a schema (or database), and multiple (sub)partitions within a table concurrently. By using concurrent statistics gathering we no longer have to run individual statistics gathering commands for each partition. Oracle will automatically create a statistics gathering job for each partition, and one for the global statistics on each partitioned table. With the use of concurrent statistics, our script can now be simplified to just five DBMS_STATS.GATHER_TABLE_STATS commands, one for each table. This approach would work just fine but we really wanted to get this down to just one command. So how can we do that? You may be wondering why we didn’t just use the DBMS_STATS.GATHER_SCHEMA_STATS procedure with the OPTION parameter set to ‘GATHER STALE’. Unfortunately the statistics on the 5 partitioned tables were not stale and enabling incremental statistics does not mark the existing statistics stale. Plus how would we limit the schema statistics gather to just the 5 partitioned tables? So we went to ask one of the statistics developers if there was an alternative way. The developer told us the advantage of the “obj_filter_list” parameter in DBMS_STATS.GATHER_SCHEMA_STATS procedure. The “obj_filter_list” parameter allows you to specify a list of objects that you want to gather statistics on within a schema or database. The parameter takes a collection of type DBMS_STATS.OBJECTTAB. Each entry in the collection has 5 feilds; the schema name or the object owner, the object type (i.e., ‘TABLE’ or ‘INDEX’), object name, partition name, and subpartition name. You don't have to specify all five fields for each entry. Empty fields in an entry are treated as if it is a wildcard field (similar to ‘*’ character in LIKE predicates). Each entry corresponds to one set of filter conditions on the objects. If you have more than one entry, an object is qualified for statistics gathering as long as it satisfies the filter conditions in one entry. You first must create the collection of objects, and then gather statistics for the specified collection. It’s probably easier to explain this with an example. I’m using the SH sample schema but needed a couple of additional partitioned table tables to get recreate my colleagues scenario of 5 partitioned tables. So I created SALES2, SALES3, and COSTS2 as copies of the SALES and COSTS table respectively (setup.sql). I also deleted statistics on all of the tables in the SH schema beforehand to more easily demonstrate our approach. Step 0. Delete the statistics on the tables in the SH schema. Step 1. Enable concurrent statistics gathering. Remember, this has to be done at the global level. Step 2. Enable incremental statistics for the 5 partitioned tables. Step 3. Create the DBMS_STATS.OBJECTTAB and pass it to the DBMS_STATS.GATHER_SCHEMA_STATS command. Here, you will notice that we defined two variables of DBMS_STATS.OBJECTTAB type. The first, filter_lst, will be used to pass the list of tables we want to gather statistics on, and will be the value passed to the obj_filter_list parameter. The second, obj_lst, will be used to capture the list of tables that have had statistics gathered on them by this command, and will be the value passed to the objlist parameter. In Oracle Database 11g Release 2, you need to specify the objlist parameter in order to get the obj_filter_list parameter to work correctly due to bug 14539274. Will also needed to define the number of objects we would supply in the obj_filter_list. In our case we ere specifying 5 tables (filter_lst.extend(5)). Finally, we need to specify the owner name and object name for each of the objects in the list. Once the list definition is complete we can issue the DBMS_STATS.GATHER_SCHEMA_STATS command. Step 4. Confirm statistics were gathered on the 5 partitioned tables. Here are a couple of other things to keep in mind when specifying the entries for the  obj_filter_list parameter. If a field in the entry is empty, i.e., null, it means there is no condition on this field. In the above example , suppose you remove the statement Obj_filter_lst(1).ownname := ‘SH’; You will get the same result since when you have specified gather_schema_stats so there is no need to further specify ownname in the obj_filter_lst. All of the names in the entry are normalized, i.e., uppercased if they are not double quoted. So in the above example, it is OK to use Obj_filter_lst(1).objname := ‘sales’;. However if you have a table called ‘MyTab’ instead of ‘MYTAB’, then you need to specify Obj_filter_lst(1).objname := ‘”MyTab”’; As I said before, although we have illustrated the usage of the obj_filter_list parameter for partitioned tables, with concurrent and incremental statistics gathering turned on, the obj_filter_list parameter is generally applicable to any gather_database_stats, gather_dictionary_stats and gather_schema_stats command. You can get a copy of the script I used to generate this post here. +Maria Colgan

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  • Getting Started With Tailoring Business Processes

    - by Richard Bingham
    In this article, and for the sake of simplicity, we will use the term “On-Premise” to mean a deployment where you have design-time development access to the instance, including administration of the technology components, the applications filesystem, and the database. In reality this might be a local development instance that is then supported by a team who can deploy your customizations to the restricted production instance equivalents. Tools Overview Firstly let’s look at the Design-Time tools within JDeveloper for customizing and extending the artifacts of a Business Process. In essence this falls into two buckets; SOA Composite Editor for working with BPEL processes, and the BPM Studio. The SOA Composite Editor As a standard extension to JDeveloper, this graphical design tool should be familiar to anyone previously worked with Oracle SOA Server. With easy-to-use modeling capability, backed-up by full XML source-view (for read-only), it provides everything that is needed to implement the technical design. In simple terms, once deployed to the remote SOA Server the composite components (like Mediator) leverage the Event Delivery Network (EDN) for interaction with the application logic. If you are customizing an existing Fusion Applications BPEL process then be aware that it does support MDS-based customization layers just like Page Composer where different customizations are used based on the run-time context, like for a specific Product or Business Unit. This also makes them safe from patching and upgrades, although only a single active version of the composite is available at run-time. This is defined by a field on the composite record, available in Enterprise Manager. Obviously if you wish to fire different activities and tasks based on the user context then you can should include switches to fork the flows in your custom BPEL process. Figure 1 – A BPEL process in Composite Editor The following describes the simplified steps for making customizations to BPEL processes. This is the most common method of changing the business processes of Fusion Applications, as over 400 BPEL-based composite applications are provided out-of-the-box. Setup your local Fusion Applications JDeveloper environment. The SOA Composite Editor should be installed as part of the Fusion Applications extension. If there are problems you can also find it under the ‘Check for Updates’ help menu option. Since SOA Server is not part of the JDeveloper integrated WebLogic Server, setup a standalone WebLogic environment for deploying and testing. Obviously you might use a Fusion Applications development instance also. Package the existing standard Fusion Applications SOA Composite using Enterprise Manager and export it as a complete SOA Archive (SAR) file, resulting in a local .jar file. You may need to ask your system administrator for this. Import the exported SAR .jar file into JDeveloper using the File menu, under the option ‘SOA Archive into SOA Project’. In JDeveloper set the appropriate customization layer values, and then change from the default role to the Fusion Applications Customization Developer role. Make the customizations and save the application project. Finally redeploy the composite application, either to a direct Application Server connection, or as a fresh SAR (jar) file that can then be re-imported and deployed via Enterprise Manager. The Business Process Management (BPM) Suite In addition to the relatively low-level development environment associated with BPEL process creation, Oracle provides a suite of products that allow business process adjustments to be made without the need for some of the programming skills.  The aim is to abstract much of the technical implementation and to provide a Business Analyst tools for immediately implementing organization changes. Obviously there are some limitations on what they can do, however the BPM Suite functionality increases with each release and for the majority of the cases the tools remains as applicable as its developer-orientated sister. At the current time business processes must be explicitly coded to support just one of these use-cases, either BPEL for developer use or BPM for business analyst use. That said, they both run on the same SOA Server in much the same way. The components bundled in each SOA Composite Application can be verified by inspection through Enterprise Manager. Figure 2 – A BPM Process in JDeveloper BPM Suite. BPM processes are written in a standard notation (BPMN) and the modeling tools are very similar to that of BPEL. The steps to deploy a custom BPM process are also essentially much the same, since the BPM process is bundled into a SOA Composite just like a BPEL process. As such the SOA Composite Editor  actually has support for both artifacts and even allows use of them together, such as a calling a BPM process as a partnerlink from a BPEL process. For more details see the references below. Business Analyst Tooling In addition to using JDeveloper extensions for BPM development, there are run-time tools that Business Analysts can use to make adjustments, so that without high costs of an IT project the system can be tuned to match changes to the business operation. The first tool to consider is the BPM Composer, deployed with the middleware SOA Server and accessible online, and for Fusion Applications it is under the Business Process icon on the homepage of the Application Composer. Figure 3 – Business Process Composer showing a CRM process flow. The key difference between this and using JDeveloper is that the BPM Composer has a Business Catalog prepopulated with features and functions that can be used, mostly through registered WebServices. This means no coding or complex interface development is required, simply drag-drop-configure. The items in the business catalog are seeded by either Oracle (as a BPM Template) or added to by your own custom development. You cannot create or generate catalog content from BPM Composer directly. As per the screenshot you can see the Business Catalog content in the BPM Project browser region. In addition, other online tools for use by Business Analysts include the BPM Worklist application for editing business rules and approval management configuration, plus the SOA Composer which focuses on non-approval business rules and domain value maps. At the current time there are only a handful of BPM processes shipped with Fusion Applications HCM and CRM, including on-boarding workers and processing customer registrations.  This also means a limited number of associated BPM Templates provided out-of-the-box, therefore a limited Business Catalog. That said, BPM-based extension is a powerful capability to leverage and will most likely develop going forwards, especially for use in SaaS deployments where full design-time JDeveloper access is not available. Further Reading For BPEL – Fusion Applications Extensibility Guide – Section 12 For BPM – Fusion Applications Extensibility Guide – Section 7 The product-specific documentation and implementation guides for Fusion Applications Fusion Middleware Developers Guide for SOA Suite Modeling and Implementation Guide for Oracle Business Process Management User’s Guide for Oracle Business Process Composer Oracle University courses on BPM Suite and SOA Development

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  • CodePlex Daily Summary for Monday, July 15, 2013

    CodePlex Daily Summary for Monday, July 15, 2013Popular ReleasesMVC Forum: MVC Forum v1.0: Finally version 1.0 is here! We have been fixing a few bugs, and making sure the release is as stable as possible. We have also changed the way configuration of the application works, mostly how to add your own code or replace some of the standard code with your own. If you download and use our software, please give us some sort of feedback, good or bad!SharePoint 2013 TypeScript Definitions: Release 1.1: TypeScript 0.9 support SharePoint TypeScript Definitions are now compliant with the new version of TypeScript TypeScript generics are now used for defining collection classes (derivatives of SP.ClientCollection object) Improved coverage Added mQuery definitions (m$) Added SPClientAutoFill definitions SP.Utilities namespace is now fully covered SP.UI modal dialog definitions improved CSR definitions improved, added some missing methods and context properties, mostly related to list ...GoAgent GUI: GoAgent GUI ??? 1.0.0: ????GoAgent GUI????,???????????.Net Framework 4.0 ???????: Windows 8 x64 Windows 8 x86 Windows 7 x64 Windows 7 x86 ???????: Windows 8.1 Preview (x86/x64) ???????: Windows XP ????: ????????GoAgent????,????????,?????????????,???????????????????,??????????,????。PiGraph: PiGraph 2.0.8.13: C?p nh?t:Các l?i dã s?a: S?a l?i không nh?p du?c s? âm. L?i tabindex trong giao di?n Thêm hàm Các l?i chua kh?c ph?c: L?i ghi chú nh?p nháy màu. L?i khung ghi chú vu?t ra kh?i biên khi luu file. Luu ý:N?u không kh?i d?ng duoc chuong trình, b?n nên c?p nh?t driver card d? h?a phiên b?n m?i nh?t: AMD Graphics Drivers NVIDIA Driver Xem yêu c?u h? th?ngD3D9Client: D3D9Client R12 for Orbiter Beta: D3D9Client release for orbiter BetaVidCoder: 1.4.23: New in 1.4.23 Added French translation. Fixed non-x264 video encoders not sticking in video tab. New in 1.4 Updated HandBrake core to 0.9.9 Blu-ray subtitle (PGS) support Additional framerates: 30, 50, 59.94, 60 Additional sample rates: 8, 11.025, 12 and 16 kHz Additional higher bitrates for audio Same as Source Constant Framerate 24-bit FLAC encoding Added Windows Phone 8 and Apple TV 3 presets Introduced process isolation for encodes. Now if HandBrake crashes, VidCoder will ...Project Server 2013 Event Handler Admin Tool: PSI Event Admin Tool: Download & exract the File. Use LoggerAdmin to upload the event handlers in project server 2013. PSIEventLogger\LoggerAdmin\bin\DebugGherkin editor: Gherkin Editor Beta 2: Fix issue #7 and add some refactoring and code cleanupNew-NuGetPackage PowerShell Script: New-NuGetPackage.ps1 PowerShell Script v1.2: Show nuget gallery to push to when prompting user if they want to push their package.Site Templates By Steve: SharePoint 2010 CORE Site Theme By Steve WSP: Great Site Theme to start with from Steve. See project home page for install instructions. This is a nice centered, mega-menu, fixed width masterpage with styles. Remember to update the mega menu lists.SharePoint Solution Installer: SharePoint Solution Installer V1.2.8: setup2013.exe now supports CompatibilityLevel to target specific hive Use setup.exe for SP2007 & SP2010. Use setup2013.exe for SP2013.TBox - tool to make developer's life easier.: TBox 1.021: 1)Add console unit tests runner, to run unit tests in parallel from console. Also this new sub tool can save valid xml nunit report. It can help you in continuous integration. 2)Fix build scripts.LifeInSharepoint Modern UI Update: Version 2: Some minor improvements, including Audience Targeting support for quick launch links. Also removing all NextDocs references.Virtual Photonics: VTS MATLAB Package 1.0.13 Beta: This is the beta release of the MATLAB package with examples of using the VTS libraries within MATLAB. Changes for this release: Added two new examples to vts_solver_demo.m that: 1) generates and plots R(lambda) at a given rho, and chromophore concentrations assuming a power law for scattering, and 2) solves inverse problem for R(lambda) at given rho. This example solves for concentrations of HbO2, Hb and H20 given simulated measurements created using Nurbs scaled Monte Carlo and inverted u...Advanced Resource Tab for Blend: Advanced Resource Tab: This is the first alpha release of the advanced resource tab for Blend for Visual Studio 2012.Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.96: Fix for issue #19957: EXE should output the name of the file(s) being minified. Discussion #449181: throw a Sev-2 warning when trailing commas are detected on an Array literal. Perfectly legal to do so, but the behavior ends up working differently on different browsers, so throw a cross-browser warning. Add a few more known global names for improved ES6 compatibility update Nuget package to version 2.5 and automatically add the AjaxMin.targets to your project when you update the package...Outlook 2013 Add-In: Categories and Colors: This new version has a major change in the drawing of the list items: - Using owner drawn code to format the appointments using GDI (some flickering may occur, but it looks a little bit better IMHO, with separate sections). - Added category color support (if more than one category, only one color will be shown). Here, the colors Outlook uses are slightly different than the ones available in System.Drawing, so I did a first approach matching. ;-) - Added appointment status support (to show fr...Columbus Remote Desktop: 2.0 Sapphire: Added configuration settings Added update notifications Added ability to disable GPU acceleration Fixed connection bugsLINQ to Twitter: LINQ to Twitter v2.1.07: Supports .NET 3.5, .NET 4.0, .NET 4.5, Silverlight 4.0, Windows Phone 7.1, Windows Phone 8, Client Profile, Windows 8, and Windows Azure. 100% Twitter API coverage. Also supports Twitter API v1.1! Also on NuGet.DotNetNuke® Community Edition CMS: 06.02.08: Major Highlights Fixed issue where the application throws an Unhandled Error and an HTTP Response Code of 200 when the connection to the database is lost. Security FixesNone Updated Modules/Providers ModulesNone ProvidersNoneNew Projects[.Net Intl] harroc_c;mallar_a;olouso_f: The goal of this project is to create a web crawler and a web front who allows you to search in your index. You will create a mini (or large!) search engine basButterfly Storage: Butterfly Storage is a data access technology based on object-oriented database model for Windows Store applications.KaveCompany: KaveCompleave that girl alone: a team project!MyClrProfiler: This project helps you learn about and develop your own CLR profiler.NETDeob: Deobfuscate obfuscated .NET files easilyProgram stomatologie: SummarySimple Graph Library: Simple portable class library for graphs data structures. .NET, Silverlight 4/5, Windows Phone, Windows RT, Xbox 360T6502 Emulator: T6502 is a 6502 emulator written in TypeScript using AngularJS. The goal is well-organized, readable code over performance.WP8 File Access Webserver: C# HTTP server and web application on Windows Phone 8. Implements file access, browsing and downloading.wpadk: wpadk????wp7?????? ?????????,?????、SDK、wpadk?????????????。??????????????????。??????????????????,????wpadk?????????????????????????????????????。xlmUnit: xlmUnit, Unit Testing

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  • CodePlex Daily Summary for Sunday, August 03, 2014

    CodePlex Daily Summary for Sunday, August 03, 2014Popular ReleasesBoxStarter: Boxstarter 2.4.76: Running the Setup.bat file will install Chocolatey if not present and then install the Boxstarter modules.GMare: GMare Beta 1.2: Features Added: - Instance painting by holding the alt key down while pressing the left mouse button - Functionality to the binary exporter so that backgrounds from image files can be used - On the binary exporter background information can be edited manually now - Update to the GMare binary read GML script - Game Maker Studio export - Import from GMare project. Multiple options to import desired properties of a .gmpx - 10 undo/redo levels instead of 5 is now the default - New preferences dia...Json.NET: Json.NET 6.0 Release 4: New feature - Added Merge to LINQ to JSON New feature - Added JValue.CreateNull and JValue.CreateUndefined New feature - Added Windows Phone 8.1 support to .NET 4.0 portable assembly New feature - Added OverrideCreator to JsonObjectContract New feature - Added support for overriding the creation of interfaces and abstract types New feature - Added support for reading UUID BSON binary values as a Guid New feature - Added MetadataPropertyHandling.Ignore New feature - Improv...SQL Server Dialog: SQL Server Dialog: Input server, user and password Show folder and file in treeview Customize icon Filter file extension Skip system generate folder and fileAitso-a platform for spatial optimization and based on artificial immune systems: Aitso_0.14.08.01: Aitso0.14.08.01Installer.zipVidCoder: 1.5.24 Beta: Added NL-Means denoiser. Updated HandBrake core to SVN 6254. Added extra error handling to DVD player code to avoid a crash when the player was moved.AutoUpdater.NET : Auto update library for VB.NET and C# Developer: AutoUpdater.NET 1.3: Fixed problem in DownloadUpdateDialog where download continues even if you close the dialog. Added support for new url field for 64 bit application setup. AutoUpdater.NET will decide which download url to use by looking at the value of IntPtr.Size. Added German translation provided by Rene Kannegiesser. Now developer can handle update logic herself using event suggested by ricorx7. Added italian translation provided by Gianluca Mariani. Fixed bug that prevents Application from exiti...SEToolbox: SEToolbox 01.041.012 Release 1: Added voxel material textures to read in with mods. Fixed missing texture replacements for mods. Fixed rounding issue in raytrace code. Fixed repair issue with corrupt checkpoint file. Fixed issue with updated SE binaries 01.041.012 using new container configuration.Magick.NET: Magick.NET 6.8.9.601: Magick.NET linked with ImageMagick 6.8.9.6 Breaking changes: - Changed arguments for the Map method of MagickImage. - QuantizeSettings uses Riemersma by default.Multiple Threads TCP Server: Project: this Project is based on VS 2013, .net freamwork 4.0, you can open it by vs 2010 or laterAricie Shared: Aricie.Shared Version 1.8.00: Version 1.8.0 - Release Notes New: Expression Builder to design Flee Expressions New: Cryptographic helpers and configuration classes Improvement: Many fixes and improvements with property editor Improvement: Token Replace Property explorer now has a restricted mode for additional security Improvement: Better variables, types and object manipulation Fixed: smart file and flee bugs Fixed: Removed Exception while trying to read unsuported files Improvement: several performance twe...Accesorios de sitios Torrent en Español para Synology Download Station: Pack de Torrents en Español 6.0.0: Agregado los módulos de DivXTotal, el módulo de búsqueda depende del de alojamiento para bajar las series Utiliza el rss: http://www.divxtotal.com/rss.php DbEntry.Net (Leafing Framework): DbEntry.Net 4.2: DbEntry.Net is a lightweight Object Relational Mapping (ORM) database access compnent for .Net 4.0+. It has clearly and easily programing interface for ORM and sql directly, and supoorted Access, Sql Server, MySql, SQLite, Firebird, PostgreSQL and Oracle. It also provide a Ruby On Rails style MVC framework. Asp.Net DataSource and a simple IoC. DbEntry.Net.v4.2.Setup.zip include the setup package. DbEntry.Net.v4.2.Src.zip include source files and unit tests. DbEntry.Net.v4.2.Samples.zip ...Azure Storage Explorer: Azure Storage Explorer 6 Preview 1: Welcome to Azure Storage Explorer 6 Preview 1 This is the first release of the latest Azure Storage Explorer, code-named Phoenix. What's New?Here are some important things to know about version 6: Open Source Now being run as a full open source project. Full source code on CodePlex. Collaboration encouraged! Updated Code Base Brand-new code base (WPF/C#/.NET 4.5) Visual Studio 2013 solution (previously VS2010) Uses the Task Parallel Library (TPL) for asynchronous background operat...Wsus Package Publisher: release v1.3.1407.29: Updated WPP to recognize the very latest console version. Some files was missing into the latest release of WPP which lead to crash when trying to make a custom update. Add a workaround to avoid clipboard modification when double-clicking on a label when creating a custom update. Add the ability to publish detectoids. (This feature is still in a BETA phase. Packages relying on these detectoids to determine which computers need to be updated, may apply to all computers).VG-Ripper & PG-Ripper: PG-Ripper 1.4.32: changes NEW: Added Support for 'ImgMega.com' links NEW: Added Support for 'ImgCandy.net' links NEW: Added Support for 'ImgPit.com' links NEW: Added Support for 'Img.yt' links FIXED: 'Radikal.ru' links FIXED: 'ImageTeam.org' links FIXED: 'ImgSee.com' links FIXED: 'Img.yt' linksAsp.Net MVC-4,Entity Framework and JQGrid Demo with Todo List WebApplication: Asp.Net MVC-4,Entity Framework and JQGrid Demo: Asp.Net MVC-4,Entity Framework and JQGrid Demo with simple Todo List WebApplication, Overview TodoList is a simple web application to create, store and modify Todo tasks to be maintained by the users, which comprises of following fields to the user (Task Name, Task Description, Severity, Target Date, Task Status). TodoList web application is created using MVC - 4 architecture, code-first Entity Framework (ORM) and Jqgrid for displaying the data.Waterfox: Waterfox 31.0 Portable: New features in Waterfox 31.0: Added support for Unicode 7.0 Experimental support for WebCL New features in Firefox 31.0:New Add the search field to the new tab page Support of Prefer:Safe http header for parental control mozilla::pkix as default certificate verifier Block malware from downloaded files Block malware from downloaded files audio/video .ogg and .pdf files handled by Firefox if no application specified Changed Removal of the CAPS infrastructure for specifying site-sp...SuperSocket, an extensible socket server framework: SuperSocket 1.6.3: The changes below are included in this release: fixed an exception when collect a server's status but it has been stopped fixed a bug that can cause an exception in case of sending data when the connection dropped already fixed the log4net missing issue for a QuickStart project fixed a warning in a QuickStart projectYnote Classic: Ynote Classic 2.8.5 Beta: Several Changes - Multiple Carets and Multiple Selections - Improved Startup Time - Improved Syntax Highlighting - Search Improvements - Shell Command - Improved StabilityNew ProjectsCreek: Creek is a Collection of many C# Frameworks and my ownSpeaking Speedometer (android): Simple speaking speedometerT125Protocol { Alpha version }: implement T125 Protocol for communicate with a mainframe.Unix Time: This library provides a System.UnixTime as a new Type providing conversion between Unix Time and .NET DateTime.

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  • Refactoring Part 1 : Intuitive Investments

    - by Wes McClure
    Fear, it’s what turns maintaining applications into a nightmare.  Technology moves on, teams move on, someone is left to operate the application, what was green is now perceived brown.  Eventually the business will evolve and changes will need to be made.  The approach to those changes often dictates the long term viability of the application.  Fear of change, lack of passion and a lack of interest in understanding the domain often leads to a paranoia to do anything that doesn’t involve duct tape and bailing twine.  Don’t get me wrong, those have a place in the short term viability of a project but they don’t have a place in the long term.  Add to it “us versus them” in regards to the original team and those that maintain it, internal politics and other factors and you have a recipe for disaster.  This results in code that quickly becomes unmanageable.  Even the most clever of designs will eventually become sub optimal and debt will amount that exponentially makes changes difficult.  This is where refactoring comes in, and it’s something I’m very passionate about.  Refactoring is about improving the process whereby we make change, it’s an exponential investment in the process of change. Without it we will incur exponential complexity that halts productivity. Investments, especially in the long term, require intuition and reflection.  How can we tackle new development effectively via evolving the original design and paying off debt that has been incurred? The longer we wait to ask and answer this question, the more it will cost us.  Small requests don’t warrant big changes, but realizing when changes now will pay off in the long term, and especially in the short term, is valuable. I have done my fair share of maintaining applications and continuously refactoring as needed, but recently I’ve begun work on a project that hasn’t had much debt, if any, paid down in years.  This is the first in a series of blog posts to try to capture the process which is largely driven by intuition of smaller refactorings from other projects. Signs that refactoring could help: Testability How can decreasing test time not pay dividends? One of the first things I found was that a very important piece often takes 30+ minutes to test.  I can only imagine how much time this has cost historically, but more importantly the time it might cost in the coming weeks: I estimate at least 10-20 hours per person!  This is simply unacceptable for almost any situation.  As it turns out, about 6 hours of working with this part of the application and I was able to cut the time down to under 30 seconds!  In less than the lost time of one week, I was able to fix the problem for all future weeks! If we can’t test fast then we can’t change fast, nor with confidence. Code is used by end users and it’s also used by developers, consider your own needs in terms of the code base.  Adding logic to enable/disable features during testing can help decouple parts of an application and lead to massive improvements.  What exactly is so wrong about test code in real code?  Often, these become features for operators and sometimes end users.  If you cannot run an integration test within a test runner in your IDE, it’s time to refactor. Readability Are variables named meaningfully via a ubiquitous language? Is the code segmented functionally or behaviorally so as to minimize the complexity of any one area? Are aspects properly segmented to avoid confusion (security, logging, transactions, translations, dependency management etc) Is the code declarative (what) or imperative (how)?  What matters, not how.  LINQ is a great abstraction of the what, not how, of collection manipulation.  The Reactive framework is a great example of the what, not how, of managing streams of data. Are constants abstracted and named, or are they just inline? Do people constantly bitch about the code/design? If the code is hard to understand, it will be hard to change with confidence.  It’s a large undertaking if the original designers didn’t pay much attention to readability and as such will never be done to “completion.”  Make sure not to go over board, instead use this as you change an application, not in lieu of changes (like with testability). Complexity Simplicity will never be achieved, it’s highly subjective.  That said, a lot of code can be significantly simplified, tidy it up as you go.  Refactoring will often converge upon a simplification step after enough time, keep an eye out for this. Understandability In the process of changing code, one often gains a better understanding of it.  Refactoring code is a good way to learn how it works.  However, it’s usually best in combination with other reasons, in effect killing two birds with one stone.  Often this is done when readability is poor, in which case understandability is usually poor as well.  In the large undertaking we are making with this legacy application, we will be replacing it.  Therefore, understanding all of its features is important and this refactoring technique will come in very handy. Unused code How can deleting things not help? This is a freebie in refactoring, it’s very easy to detect with modern tools, especially in statically typed languages.  We have VCS for a reason, if in doubt, delete it out (ok that was cheesy)! If you don’t know where to start when refactoring, this is an excellent starting point! Duplication Do not pray and sacrifice to the anti-duplication gods, there are excellent examples where consolidated code is a horrible idea, usually with divergent domains.  That said, mediocre developers live by copy/paste.  Other times features converge and aren’t combined.  Tools for finding similar code are great in the example of copy/paste problems.  Knowledge of the domain helps identify convergent concepts that often lead to convergent solutions and will give intuition for where to look for conceptual repetition. 80/20 and the Boy Scouts It’s often said that 80% of the time 20% of the application is used most.  These tend to be the parts that are changed.  There are also parts of the code where 80% of the time is spent changing 20% (probably for all the refactoring smells above).  I focus on these areas any time I make a change and follow the philosophy of the Boy Scout in cleaning up more than I messed up.  If I spend 2 hours changing an application, in the 20%, I’ll always spend at least 15 minutes cleaning it or nearby areas. This gives a huge productivity edge on developers that don’t. Ironically after a short period of time the 20% shrinks enough that we don’t have to spend 80% of our time there and can move on to other areas.   Refactoring is highly subjective, never attempt to refactor to completion!  Learn to be comfortable with leaving one part of the application in a better state than others.  It’s an evolution, not a revolution.  These are some simple areas to look into when making changes and can help get one started in the process.  I’ve often found that refactoring is a convergent process towards simplicity that sometimes spans a few hours but often can lead to massive simplifications over the timespan of weeks and months of regular development.

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  • When is a Seek not a Seek?

    - by Paul White
    The following script creates a single-column clustered table containing the integers from 1 to 1,000 inclusive. IF OBJECT_ID(N'tempdb..#Test', N'U') IS NOT NULL DROP TABLE #Test ; GO CREATE TABLE #Test ( id INTEGER PRIMARY KEY CLUSTERED ); ; INSERT #Test (id) SELECT V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 1000 ; Let’s say we need to find the rows with values from 100 to 170, excluding any values that divide exactly by 10.  One way to write that query would be: SELECT T.id FROM #Test AS T WHERE T.id IN ( 101,102,103,104,105,106,107,108,109, 111,112,113,114,115,116,117,118,119, 121,122,123,124,125,126,127,128,129, 131,132,133,134,135,136,137,138,139, 141,142,143,144,145,146,147,148,149, 151,152,153,154,155,156,157,158,159, 161,162,163,164,165,166,167,168,169 ) ; That query produces a pretty efficient-looking query plan: Knowing that the source column is defined as an INTEGER, we could also express the query this way: SELECT T.id FROM #Test AS T WHERE T.id >= 101 AND T.id <= 169 AND T.id % 10 > 0 ; We get a similar-looking plan: If you look closely, you might notice that the line connecting the two icons is a little thinner than before.  The first query is estimated to produce 61.9167 rows – very close to the 63 rows we know the query will return.  The second query presents a tougher challenge for SQL Server because it doesn’t know how to predict the selectivity of the modulo expression (T.id % 10 > 0).  Without that last line, the second query is estimated to produce 68.1667 rows – a slight overestimate.  Adding the opaque modulo expression results in SQL Server guessing at the selectivity.  As you may know, the selectivity guess for a greater-than operation is 30%, so the final estimate is 30% of 68.1667, which comes to 20.45 rows. The second difference is that the Clustered Index Seek is costed at 99% of the estimated total for the statement.  For some reason, the final SELECT operator is assigned a small cost of 0.0000484 units; I have absolutely no idea why this is so, or what it models.  Nevertheless, we can compare the total cost for both queries: the first one comes in at 0.0033501 units, and the second at 0.0034054.  The important point is that the second query is costed very slightly higher than the first, even though it is expected to produce many fewer rows (20.45 versus 61.9167). If you run the two queries, they produce exactly the same results, and both complete so quickly that it is impossible to measure CPU usage for a single execution.  We can, however, compare the I/O statistics for a single run by running the queries with STATISTICS IO ON: Table '#Test'. Scan count 63, logical reads 126, physical reads 0. Table '#Test'. Scan count 01, logical reads 002, physical reads 0. The query with the IN list uses 126 logical reads (and has a ‘scan count’ of 63), while the second query form completes with just 2 logical reads (and a ‘scan count’ of 1).  It is no coincidence that 126 = 63 * 2, by the way.  It is almost as if the first query is doing 63 seeks, compared to one for the second query. In fact, that is exactly what it is doing.  There is no indication of this in the graphical plan, or the tool-tip that appears when you hover your mouse over the Clustered Index Seek icon.  To see the 63 seek operations, you have click on the Seek icon and look in the Properties window (press F4, or right-click and choose from the menu): The Seek Predicates list shows a total of 63 seek operations – one for each of the values from the IN list contained in the first query.  I have expanded the first seek node to show the details; it is seeking down the clustered index to find the entry with the value 101.  Each of the other 62 nodes expands similarly, and the same information is contained (even more verbosely) in the XML form of the plan. Each of the 63 seek operations starts at the root of the clustered index B-tree and navigates down to the leaf page that contains the sought key value.  Our table is just large enough to need a separate root page, so each seek incurs 2 logical reads (one for the root, and one for the leaf).  We can see the index depth using the INDEXPROPERTY function, or by using the a DMV: SELECT S.index_type_desc, S.index_depth FROM sys.dm_db_index_physical_stats ( DB_ID(N'tempdb'), OBJECT_ID(N'tempdb..#Test', N'U'), 1, 1, DEFAULT ) AS S ; Let’s look now at the Properties window when the Clustered Index Seek from the second query is selected: There is just one seek operation, which starts at the root of the index and navigates the B-tree looking for the first key that matches the Start range condition (id >= 101).  It then continues to read records at the leaf level of the index (following links between leaf-level pages if necessary) until it finds a row that does not meet the End range condition (id <= 169).  Every row that meets the seek range condition is also tested against the Residual Predicate highlighted above (id % 10 > 0), and is only returned if it matches that as well. You will not be surprised that the single seek (with a range scan and residual predicate) is much more efficient than 63 singleton seeks.  It is not 63 times more efficient (as the logical reads comparison would suggest), but it is around three times faster.  Let’s run both query forms 10,000 times and measure the elapsed time: DECLARE @i INTEGER, @n INTEGER = 10000, @s DATETIME = GETDATE() ; SET NOCOUNT ON; SET STATISTICS XML OFF; ; WHILE @n > 0 BEGIN SELECT @i = T.id FROM #Test AS T WHERE T.id IN ( 101,102,103,104,105,106,107,108,109, 111,112,113,114,115,116,117,118,119, 121,122,123,124,125,126,127,128,129, 131,132,133,134,135,136,137,138,139, 141,142,143,144,145,146,147,148,149, 151,152,153,154,155,156,157,158,159, 161,162,163,164,165,166,167,168,169 ) ; SET @n -= 1; END ; PRINT DATEDIFF(MILLISECOND, @s, GETDATE()) ; GO DECLARE @i INTEGER, @n INTEGER = 10000, @s DATETIME = GETDATE() ; SET NOCOUNT ON ; WHILE @n > 0 BEGIN SELECT @i = T.id FROM #Test AS T WHERE T.id >= 101 AND T.id <= 169 AND T.id % 10 > 0 ; SET @n -= 1; END ; PRINT DATEDIFF(MILLISECOND, @s, GETDATE()) ; On my laptop, running SQL Server 2008 build 4272 (SP2 CU2), the IN form of the query takes around 830ms and the range query about 300ms.  The main point of this post is not performance, however – it is meant as an introduction to the next few parts in this mini-series that will continue to explore scans and seeks in detail. When is a seek not a seek?  When it is 63 seeks © Paul White 2011 email: [email protected] twitter: @SQL_kiwi

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  • Real tortoises keep it slow and steady. How about the backups?

    - by Maria Zakourdaev
      … Four tortoises were playing in the backyard when they decided they needed hibiscus flower snacks. They pooled their money and sent the smallest tortoise out to fetch the snacks. Two days passed and there was no sign of the tortoise. "You know, she is taking a lot of time", said one of the tortoises. A little voice from just out side the fence said, "If you are going to talk that way about me I won't go." Is it too much to request from the quite expensive 3rd party backup tool to be a way faster than the SQL server native backup? Or at least save a respectable amount of storage by producing a really smaller backup files?  By saying “really smaller”, I mean at least getting a file in half size. After Googling the internet in an attempt to understand what other “sql people” are using for database backups, I see that most people are using one of three tools which are the main players in SQL backup area:  LiteSpeed by Quest SQL Backup by Red Gate SQL Safe by Idera The feedbacks about those tools are truly emotional and happy. However, while reading the forums and blogs I have wondered, is it possible that many are accustomed to using the above tools since SQL 2000 and 2005.  This can easily be understood due to the fact that a 300GB database backup for instance, using regular a SQL 2005 backup statement would have run for about 3 hours and have produced ~150GB file (depending on the content, of course).  Then you take a 3rd party tool which performs the same backup in 30 minutes resulting in a 30GB file leaving you speechless, you run to management persuading them to buy it due to the fact that it is definitely worth the price. In addition to the increased speed and disk space savings you would also get backup file encryption and virtual restore -  features that are still missing from the SQL server. But in case you, as well as me, don’t need these additional features and only want a tool that performs a full backup MUCH faster AND produces a far smaller backup file (like the gain you observed back in SQL 2005 days) you will be quite disappointed. SQL Server backup compression feature has totally changed the market picture. Medium size database. Take a look at the table below, check out how my SQL server 2008 R2 compares to other tools when backing up a 300GB database. It appears that when talking about the backup speed, SQL 2008 R2 compresses and performs backup in similar overall times as all three other tools. 3rd party tools maximum compression level takes twice longer. Backup file gain is not that impressive, except the highest compression levels but the price that you pay is very high cpu load and much longer time. Only SQL Safe by Idera was quite fast with it’s maximum compression level but most of the run time have used 95% cpu on the server. Note that I have used two types of destination storage, SATA 11 disks and FC 53 disks and, obviously, on faster storage have got my backup ready in half time. Looking at the above results, should we spend money, bother with another layer of complexity and software middle-man for the medium sized databases? I’m definitely not going to do so.  Very large database As a next phase of this benchmark, I have moved to a 6 terabyte database which was actually my main backup target. Note, how multiple files usage enables the SQL Server backup operation to use parallel I/O and remarkably increases it’s speed, especially when the backup device is heavily striped. SQL Server supports a maximum of 64 backup devices for a single backup operation but the most speed is gained when using one file per CPU, in the case above 8 files for a 2 Quad CPU server. The impact of additional files is minimal.  However, SQLsafe doesn’t show any speed improvement between 4 files and 8 files. Of course, with such huge databases every half percent of the compression transforms into the noticeable numbers. Saving almost 470GB of space may turn the backup tool into quite valuable purchase. Still, the backup speed and high CPU are the variables that should be taken into the consideration. As for us, the backup speed is more critical than the storage and we cannot allow a production server to sustain 95% cpu for such a long time. Bottomline, 3rd party backup tool developers, we are waiting for some breakthrough release. There are a few unanswered questions, like the restore speed comparison between different tools and the impact of multiple backup files on restore operation. Stay tuned for the next benchmarks.    Benchmark server: SQL Server 2008 R2 sp1 2 Quad CPU Database location: NetApp FC 15K Aggregate 53 discs Backup statements: No matter how good that UI is, we need to run the backup tasks from inside of SQL Server Agent to make sure they are covered by our monitoring systems. I have used extended stored procedures (command line execution also is an option, I haven’t noticed any impact on the backup performance). SQL backup LiteSpeed SQL Backup SQL safe backup database <DBNAME> to disk= '\\<networkpath>\par1.bak' , disk= '\\<networkpath>\par2.bak', disk= '\\<networkpath>\par3.bak' with format, compression EXECUTE master.dbo.xp_backup_database @database = N'<DBName>', @backupname= N'<DBName> full backup', @desc = N'Test', @compressionlevel=8, @filename= N'\\<networkpath>\par1.bak', @filename= N'\\<networkpath>\par2.bak', @filename= N'\\<networkpath>\par3.bak', @init = 1 EXECUTE master.dbo.sqlbackup '-SQL "BACKUP DATABASE <DBNAME> TO DISK= ''\\<networkpath>\par1.sqb'', DISK= ''\\<networkpath>\par2.sqb'', DISK= ''\\<networkpath>\par3.sqb'' WITH DISKRETRYINTERVAL = 30, DISKRETRYCOUNT = 10, COMPRESSION = 4, INIT"' EXECUTE master.dbo.xp_ss_backup @database = 'UCMSDB', @filename = '\\<networkpath>\par1.bak', @backuptype = 'Full', @compressionlevel = 4, @backupfile = '\\<networkpath>\par2.bak', @backupfile = '\\<networkpath>\par3.bak' If you still insist on using 3rd party tools for the backups in your production environment with maximum compression level, you will definitely need to consider limiting cpu usage which will increase the backup operation time even more: RedGate : use THREADPRIORITY option ( values 0 – 6 ) LiteSpeed : use  @throttle ( percentage, like 70%) SQL safe :  the only thing I have found was @Threads option.   Yours, Maria

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  • SQL SERVER – Weekly Series – Memory Lane – #031

    - by Pinal Dave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Find Table without Clustered Index – Find Table with no Primary Key Clustered index is very important concept for any table. They impact the performance very heavily. Here is a quick script to find tables without a clustered index. Replace TEXT with VARCHAR(MAX) – Stop using TEXT, NTEXT, IMAGE Data Types Question: “Is VARCHAR (MAX) big enough to store the TEXT field?” Answer: “Yes, VARCHAR(MAX) is big enough to accommodate TEXT field. TEXT, NTEXT and IMAGE data types of SQL Server 2000 will be deprecated in a future version of SQL Server, SQL Server 2005 provides backward compatibility to data types but it is recommended to use new data types which are VARHCAR (MAX), NVARCHAR (MAX) and VARBINARY (MAX).” Limiting Result Sets by Using TABLESAMPLE – Examples Introduced in SQL Server 2005, TABLESAMPLE allows you to extract a sampling of rows from a table in the FROM clause. The rows retrieved are random and they are are not in any order. This sampling can be based on a percentage of number of rows. You can use TABLESAMPLE when only a sampling of rows is necessary for the application instead of a full result set. User Defined Functions (UDF) Limitations UDF have its own advantage and usage but in this article we will see the limitation of UDF. Things UDF can not do and why Stored Procedure are considered as more flexible then UDFs. Stored Procedure are more flexibility then User Defined Functions(UDF). However, this blog post is a good read to know what are the limitations of UDF. Change Database Compatible Level – Backward Compatibility For a long time SQL Server stayed on the compatibility level of 80 which is of SQL Server 2000. However, as soon as SQL Server 2005 introduced the issue of compatibility was quite a major issue. Since that time MS has been releasing the versions at every 2-3 years, changing compatibility is a ever popular topic. In this blog post, we learn how we can do the same using T-SQL. We can also do the same using SSMS and here is the blog post for the same: Change Database Compatible Level – Backward Compatibility – Part 2 – Management Studio. Constraint on VARCHAR(MAX) Field To Limit It Certain Length How can I limit the VARCHAR(MAX) field with maximum length of 12500 characters only. His Question was valid as our application was allowed 12500 characters. First of all – this requirement is bit strange but if someone wants to do the same, they can do it as described in this blog post. 2008 UNPIVOT Table Example Understanding UNPIVOT can be very complicated at times. In this blog post, I have attempted to explain the same concept in very simple words. Create Default Constraint Over Table Column A simple straight to script blog post – I still use this blog quite many times for my own reference. UDF – Get the Day of the Week Function It took me 4 iteration to find this very simple function which can immediately get the day of the week in a single line. 2009 Find Hostname and Current Logged In User Name There are two tricks listed in this blog post where users can find out the hostname and current logged user name immediately and very easily. Interesting Observation of Logon Trigger On All Servers When I was doing a project, I made an interesting observation of executing a logon trigger multiple times. It was absolutely unexpected for me! As I was logging only once, naturally, I was expecting the entry only once. However, it did it multiple times on different threads – indeed an eccentric phenomenon at first sight! Difference Between Candidate Keys and Primary Key One needs to be very careful in selecting the Primary Key as an incorrect selection can adversely impact the database architect and future normalization. For a Candidate Key to qualify as a Primary Key, it should be Non-NULL and unique in any domain. I have observed quite often that Primary Keys are seldom changed. I would like to have your feedback on not changing a Primary Key. Create Multiple Filegroup For Single Database Why should one create multiple file group for any database and what are the advantages of the same. In this blog post, I explain the same in detail. List All Objects Created on All Filegroups in Database In this blog post we discuss the essential question – “How can I find which object belongs to which filegroup. Is there any way to know this?” 2010 DATE and TIME in SQL Server 2008 When DATE is converted to DATETIME it adds the of midnight. When TIME is converted to DATETIME it adds the date of 1900 and it is something one wants to consider if you are going to run scripts from SQL Server 2008 to earlier version with CONVERT. Disabled Index and Update Statistics If you do not need a nonclustered index, I suggest you to drop it as keeping them disabled is an overhead on your system. This is because every time the statistics are updated for system all the statistics for disabled indexes are also updated. Precision of SMALLDATETIME – A 1 Minute Precision The precision of the datatype SMALLDATETIME is 1 minute. It discards the seconds by rounding up or rounding down any seconds greater than zero. 2011 Getting Columns Headers without Result Data – SET FMTONLY ON SET FMTONLY ON returns only metadata to the client. It can be used to test the format of the response without actually running the query. When this setting is ON the resultset only have headers of the results but no data. Copy Database from Instance to Another Instance – Copy Paste in SQL Server SQL Server has a feature which copy database from one database to another database and it can be automated as well using SSIS. Make sure you have SQL Server Agent Turned on as this feature will create a job. Puzzle – SELECT * vs SELECT COUNT(*) If you have ever wondered SELECT * gives error when executed alone but SELECT COUNT(*) does not. Why? in that case, you should read this blog post. Creating All New Database with Full Recovery Model This blog post is very based on very interesting story where the user wants to do something by default for every single new database created. Model database is a secret weapon which should be used very carefully and with proper evalution. If used carefully this can be a very much beneficiary when we need a newly created database behave in certain fashion. 2012 In year 2012 I had two interesting series ran on the blog. If there is no fun in learning, the learning becomes a burden. For the same reason, I had decided to build a three part quiz around SEQUENCE. The quiz was to identify the next value of the sequence. I encourage all of you to take part in this fun quiz. Guess the Next Value – Puzzle 1 Guess the Next Value – Puzzle 2 Guess the Next Value – Puzzle 3 Can anyone remember their final day of schooling?  This is probably a silly question because – of course you can!  Many people mark this as the most exciting, happiest day of their life.  It marks the end of testing, the end of following rules set by teachers, and the beginning of finally being able to earn money and work in your chosen field. Read five part series on developer training subject Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Fun with Aggregates

    - by Paul White
    There are interesting things to be learned from even the simplest queries.  For example, imagine you are given the task of writing a query to list AdventureWorks product names where the product has at least one entry in the transaction history table, but fewer than ten. One possible query to meet that specification is: SELECT p.Name FROM Production.Product AS p JOIN Production.TransactionHistory AS th ON p.ProductID = th.ProductID GROUP BY p.ProductID, p.Name HAVING COUNT_BIG(*) < 10; That query correctly returns 23 rows (execution plan and data sample shown below): The execution plan looks a bit different from the written form of the query: the base tables are accessed in reverse order, and the aggregation is performed before the join.  The general idea is to read all rows from the history table, compute the count of rows grouped by ProductID, merge join the results to the Product table on ProductID, and finally filter to only return rows where the count is less than ten. This ‘fully-optimized’ plan has an estimated cost of around 0.33 units.  The reason for the quote marks there is that this plan is not quite as optimal as it could be – surely it would make sense to push the Filter down past the join too?  To answer that, let’s look at some other ways to formulate this query.  This being SQL, there are any number of ways to write logically-equivalent query specifications, so we’ll just look at a couple of interesting ones.  The first query is an attempt to reverse-engineer T-SQL from the optimized query plan shown above.  It joins the result of pre-aggregating the history table to the Product table before filtering: SELECT p.Name FROM ( SELECT th.ProductID, cnt = COUNT_BIG(*) FROM Production.TransactionHistory AS th GROUP BY th.ProductID ) AS q1 JOIN Production.Product AS p ON p.ProductID = q1.ProductID WHERE q1.cnt < 10; Perhaps a little surprisingly, we get a slightly different execution plan: The results are the same (23 rows) but this time the Filter is pushed below the join!  The optimizer chooses nested loops for the join, because the cardinality estimate for rows passing the Filter is a bit low (estimate 1 versus 23 actual), though you can force a merge join with a hint and the Filter still appears below the join.  In yet another variation, the < 10 predicate can be ‘manually pushed’ by specifying it in a HAVING clause in the “q1” sub-query instead of in the WHERE clause as written above. The reason this predicate can be pushed past the join in this query form, but not in the original formulation is simply an optimizer limitation – it does make efforts (primarily during the simplification phase) to encourage logically-equivalent query specifications to produce the same execution plan, but the implementation is not completely comprehensive. Moving on to a second example, the following query specification results from phrasing the requirement as “list the products where there exists fewer than ten correlated rows in the history table”: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) < 10 ); Unfortunately, this query produces an incorrect result (86 rows): The problem is that it lists products with no history rows, though the reasons are interesting.  The COUNT_BIG(*) in the EXISTS clause is a scalar aggregate (meaning there is no GROUP BY clause) and scalar aggregates always produce a value, even when the input is an empty set.  In the case of the COUNT aggregate, the result of aggregating the empty set is zero (the other standard aggregates produce a NULL).  To make the point really clear, let’s look at product 709, which happens to be one for which no history rows exist: -- Scalar aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709;   -- Vector aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709 GROUP BY th.ProductID; The estimated execution plans for these two statements are almost identical: You might expect the Stream Aggregate to have a Group By for the second statement, but this is not the case.  The query includes an equality comparison to a constant value (709), so all qualified rows are guaranteed to have the same value for ProductID and the Group By is optimized away. In fact there are some minor differences between the two plans (the first is auto-parameterized and qualifies for trivial plan, whereas the second is not auto-parameterized and requires cost-based optimization), but there is nothing to indicate that one is a scalar aggregate and the other is a vector aggregate.  This is something I would like to see exposed in show plan so I suggested it on Connect.  Anyway, the results of running the two queries show the difference at runtime: The scalar aggregate (no GROUP BY) returns a result of zero, whereas the vector aggregate (with a GROUP BY clause) returns nothing at all.  Returning to our EXISTS query, we could ‘fix’ it by changing the HAVING clause to reject rows where the scalar aggregate returns zero: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) BETWEEN 1 AND 9 ); The query now returns the correct 23 rows: Unfortunately, the execution plan is less efficient now – it has an estimated cost of 0.78 compared to 0.33 for the earlier plans.  Let’s try adding a redundant GROUP BY instead of changing the HAVING clause: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY th.ProductID HAVING COUNT_BIG(*) < 10 ); Not only do we now get correct results (23 rows), this is the execution plan: I like to compare that plan to quantum physics: if you don’t find it shocking, you haven’t understood it properly :)  The simple addition of a redundant GROUP BY has resulted in the EXISTS form of the query being transformed into exactly the same optimal plan we found earlier.  What’s more, in SQL Server 2008 and later, we can replace the odd-looking GROUP BY with an explicit GROUP BY on the empty set: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ); I offer that as an alternative because some people find it more intuitive (and it perhaps has more geek value too).  Whichever way you prefer, it’s rather satisfying to note that the result of the sub-query does not exist for a particular correlated value where a vector aggregate is used (the scalar COUNT aggregate always returns a value, even if zero, so it always ‘EXISTS’ regardless which ProductID is logically being evaluated). The following query forms also produce the optimal plan and correct results, so long as a vector aggregate is used (you can probably find more equivalent query forms): WHERE Clause SELECT p.Name FROM Production.Product AS p WHERE ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) < 10; APPLY SELECT p.Name FROM Production.Product AS p CROSS APPLY ( SELECT NULL FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ) AS ca (dummy); FROM Clause SELECT q1.Name FROM ( SELECT p.Name, cnt = ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) FROM Production.Product AS p ) AS q1 WHERE q1.cnt < 10; This last example uses SUM(1) instead of COUNT and does not require a vector aggregate…you should be able to work out why :) SELECT q.Name FROM ( SELECT p.Name, cnt = ( SELECT SUM(1) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID ) FROM Production.Product AS p ) AS q WHERE q.cnt < 10; The semantics of SQL aggregates are rather odd in places.  It definitely pays to get to know the rules, and to be careful to check whether your queries are using scalar or vector aggregates.  As we have seen, query plans do not show in which ‘mode’ an aggregate is running and getting it wrong can cause poor performance, wrong results, or both. © 2012 Paul White Twitter: @SQL_Kiwi email: [email protected]

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  • The Presentation Isn't Over Until It's Over

    - by Phil Factor
    The senior corporate dignitaries settled into their seats looking important in a blue-suited sort of way. The lights dimmed as I strode out in front to give my presentation.  I had ten vital minutes to make my pitch.  I was about to dazzle the top management of a large software company who were considering the purchase of my software product. I would present them with a dazzling synthesis of diagrams, graphs, followed by  a live demonstration of my software projected from my laptop.  My preparation had been meticulous: It had to be: A year’s hard work was at stake, so I’d prepared it to perfection.  I stood up and took them all in, with a gaze of sublime confidence. Then the laptop expired. There are several possible alternative plans of action when this happens     A. Stare at the smoking laptop vacuously, flapping ones mouth slowly up and down     B. Stand frozen like a statue, locked in indecision between fright and flight.     C. Run out of the room, weeping     D. Pretend that this was all planned     E. Abandon the presentation in favour of a stilted and tedious dissertation about the software     F. Shake your fist at the sky, and curse the sense of humour of your preferred deity I started for a few seconds on plan B, normally referred to as the ‘Rabbit in the headlamps of the car’ technique. Suddenly, a little voice inside my head spoke. It spoke the famous inane words of Yogi Berra; ‘The game isn't over until it's over.’ ‘Too right’, I thought. What to do? I ran through the alternatives A-F inclusive in my mind but none appealed to me. I was completely unprepared for this. Nowadays, longevity has since taught me more than I wanted to know about the wacky sense of humour of fate, and I would have taken two laptops. I hadn’t, but decided to do the presentation anyway as planned. I started out ignoring the dead laptop, but pretending, instead that it was still working. The audience looked startled. They were expecting plan B to be succeeded by plan C, I suspect. They weren’t used to denial on this scale. After my introductory talk, which didn’t require any visuals, I came to the diagram that described the application I’d written.  I’d taken ages over it and it was hot stuff. Well, it would have been had it been projected onto the screen. It wasn’t. Before I describe what happened then, I must explain that I have thespian tendencies.  My  triumph as Professor Higgins in My Fair Lady at the local operatic society is now long forgotten, but I remember at the time of my finest performance, the moment that, glancing up over the vast audience of  moist-eyed faces at the during the poignant  scene between Eliza and Higgins at the end, I  realised that I had a talent that one day could possibly  be harnessed for commercial use I just talked about the diagram as if it was there, but throwing in some extra description. The audience nodded helpfully when I’d done enough. Emboldened, I began a sort of mime, well, more of a ballet, to represent each slide as I came to it. Heaven knows I’d done my preparation and, in my mind’s eye, I could see every detail, but I had to somehow project the reality of that vision to the audience, much the same way any actor playing Macbeth should do the ghost of Banquo.  My desperation gave me a manic energy. If you’ve ever demonstrated a windows application entirely by mime, gesture and florid description, you’ll understand the scale of the challenge, but then I had nothing to lose. With a brief sentence of description here and there, and arms flailing whilst outlining the size and shape of  graphs and diagrams, I used the many tricks of mime, gesture and body-language  learned from playing Captain Hook, or the Sheriff of Nottingham in pantomime. I set out determinedly on my desperate venture. There wasn’t time to do anything but focus on the challenge of the task: the world around me narrowed down to ten faces and my presentation: ten souls who had to be hypnotized into seeing a Windows application:  one that was slick, well organized and functional I don’t remember the details. Eight minutes of my life are gone completely. I was a thespian berserker.  I know however that I followed the basic plan of building the presentation in a carefully controlled crescendo until the dazzling finale where the results were displayed on-screen.  ‘And here you see the results, neatly formatted and grouped carefully to enhance the significance of the figures, together with running trend-graphs!’ I waved a mime to signify an animated  window-opening, and looked up, in my first pause, to gaze defiantly  at the audience.  It was a sight I’ll never forget. Ten pairs of eyes were gazing in rapt attention at the imaginary window, and several pairs of eyes were glancing at the imaginary graphs and figures.  I hadn’t had an audience like that since my starring role in  Beauty and the Beast.  At that moment, I realized that my desperate ploy might work. I sat down, slightly winded, when my ten minutes were up.  For the first and last time in my life, the audience of a  ‘PowerPoint’ presentation burst into spontaneous applause. ‘Any questions?’ ‘Yes,  Have you got an agent?’ Yes, in case you’re wondering, I got the deal. They bought the software product from me there and then. However, it was a life-changing experience for me and I have never ever again trusted technology as part of a presentation.  Even if things can’t go wrong, they’ll go wrong and they’ll kill the flow of what you’re presenting.  if you can’t do something without the techno-props, then you shouldn’t do it.  The greatest lesson of all is that great presentations require preparation and  ‘stage-presence’ rather than fancy graphics. They’re a great supporting aid, but they should never dominate to the point that you’re lost without them.

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  • Five Key Strategies in Master Data Management

    - by david.butler(at)oracle.com
    Here is a very interesting Profit Magazine article on MDM: A recent customer survey reveals the deleterious effects of data fragmentation. by Trevor Naidoo, December 2010   Across industries and geographies, IT organizations have grown in complexity, whether due to mergers and acquisitions, or decentralized systems supporting functional or departmental requirements. With systems architected over time to support unique, one-off process needs, they are becoming costly to maintain, and the Internet has only further added to the complexity. Data fragmentation has become a key inhibitor in delivering flexible, user-friendly systems. The Oracle Insight team conducted a survey assessing customers' master data management (MDM) capabilities over the past two years to get a sense of where they are in terms of their capabilities. The responses, by 27 respondents from six different industries, reveal five key areas in which customers need to improve their data management in order to get better financial results. 1. Less than 15 percent of organizations surveyed understand the sources and quality of their master data, and have a roadmap to address missing data domains. Examples of the types of master data domains referred to are customer, supplier, product, financial and site. Many organizations have multiple sources of master data with varying degrees of data quality in each source -- customer data stored in the customer relationship management system is inconsistent with customer data stored in the order management system. Imagine not knowing how many places you stored your customer information, and whether a customer's address was the most up to date in each source. In fact, more than 55 percent of the respondents in the survey manage their data quality on an ad-hoc basis. It is important for organizations to document their inventory of data sources and then profile these data sources to ensure that there is a consistent definition of key data entities throughout the organization. Some questions to ask are: How do we define a customer? What is a product? How do we define a site? The goal is to strive for one common repository for master data that acts as a cross reference for all other sources and ensures consistent, high-quality master data throughout the organization. 2. Only 18 percent of respondents have an enterprise data management strategy to ensure that data is treated as an asset to the organization. Most respondents handle data at the department or functional level and do not have an enterprise view of their master data. The sales department may track all their interactions with customers as they move through the sales cycle, the service department is tracking their interactions with the same customers independently, and the finance department also has a different perspective on the same customer. The salesperson may not be aware that the customer she is trying to sell to is experiencing issues with existing products purchased, or that the customer is behind on previous invoices. The lack of a data strategy makes it difficult for business users to turn data into information via reports. Without the key building blocks in place, it is difficult to create key linkages between customer, product, site, supplier and financial data. These linkages make it possible to understand patterns. A well-defined data management strategy is aligned to the business strategy and helps create the governance needed to ensure that data stewardship is in place and data integrity is intact. 3. Almost 60 percent of respondents have no strategy to integrate data across operational applications. Many respondents have several disparate sources of data with no strategy to keep them in sync with each other. Even though there is no clear strategy to integrate the data (see #2 above), the data needs to be synced and cross-referenced to keep the business processes running. About 55 percent of respondents said they perform this integration on an ad hoc basis, and in many cases, it is done manually with the help of Microsoft Excel spreadsheets. For example, a salesperson needs a report on global sales for a specific product, but the product has different product numbers in different countries. Typically, an analyst will pull all the data into Excel, manually create a cross reference for that product, and then aggregate the sales. The exact same procedure has to be followed if the same report is needed the following month. A well-defined consolidation strategy will ensure that a central cross-reference is maintained with updates in any one application being propagated to all the other systems, so that data is synchronized and up to date. This can be done in real time or in batch mode using integration technology. 4. Approximately 50 percent of respondents spend manual efforts cleansing and normalizing data. Information stored in various systems usually follows different standards and formats, making it difficult to match the data. A customer's address can be stored in different ways using a variety of abbreviations -- for example, "av" or "ave" for avenue. Similarly, a product's attributes can be stored in a number of different ways; for example, a size attribute can be stored in inches and can also be entered as "'' ". These types of variations make it difficult to match up data from different sources. Today, most customers rely on manual, heroic efforts to match, cleanse, and de-duplicate data -- clearly not a scalable, sustainable model. To solve this challenge, organizations need the ability to standardize data for customers, products, sites, suppliers and financial accounts; however, less than 10 percent of respondents have technology in place to automatically resolve duplicates. It is no wonder, therefore, that we get communications about products we don't own, at addresses we don't reside, and using channels (like direct mail) we don't like. An all-too-common example of a potential challenge follows: Customers end up receiving duplicate communications, which not only impacts customer satisfaction, but also incurs additional mailing costs. Cleansing, normalizing, and standardizing data will help address most of these issues. 5. Only 10 percent of respondents have the ability to share data that was mastered in a master data hub. Close to 60 percent of respondents have efforts in place that profile, standardize and cleanse data manually, and the output of these efforts are stored in spreadsheets in various parts of the organization. This valuable information is not easily shared with the rest of the organization and, more importantly, this enriched information cannot be sent back to the source systems so that the data is fixed at the source. A key benefit of a master data management strategy is not only to clean the data, but to also share the data back to the source systems as well as other systems that need the information. Aside from the source systems, another key beneficiary of this data is the business intelligence system. Having clean master data as input to business intelligence systems provides more accurate and enhanced reporting.  Characteristics of Stellar MDM When deciding on the right master data management technology, organizations should look for solutions that have four main characteristics: enterprise-grade MDM performance complete technology that can be rapidly deployed and addresses multiple business issues end-to-end MDM process management with data quality monitoring and assurance pre-built MDM business relevant applications with data stores and workflows These master data management capabilities will aid in moving closer to a best-practice maturity level, delivering tremendous efficiencies and savings as well as revenue growth opportunities as a result of better understanding your customers.  Trevor Naidoo is a senior director in Industry Strategy and Insight at Oracle. 

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  • CodePlex Daily Summary for Saturday, June 16, 2012

    CodePlex Daily Summary for Saturday, June 16, 2012Popular ReleasesCosmos (C# Open Source Managed Operating System): Release 92560: Prerequisites Visual Studio 2010 - Any version including Express. Express users must also install Visual Studio 2010 Integrated Shell runtime VMWare - Cosmos can run on real hardware as well as other virtualization environments but our default debug setup is configured for VMWare. VMWare Player (Free). or Workstation VMWare VIX API 1.11AutoUpdaterdotNET : Autoupdate for VB.NET and C# Developer: AutoUpdater.NET 1.1: Release Notes *New feature added that allows user to select remind later interval.Sumzlib: API document: API documentMicrosoft SQL Server Product Samples: Database: AdventureWorks 2008 OLTP Script: Install AdventureWorks2008 OLTP database from script The AdventureWorks database can be created by running the instawdb.sql DDL script contained in the AdventureWorks 2008 OLTP Script.zip file. The instawdb.sql script depends on two path environment variables: SqlSamplesDatabasePath and SqlSamplesSourceDataPath. The SqlSamplesDatabasePath environment variable is set to the default Microsoft ® SQL Server 2008 path. You will need to change the SqlSamplesSourceDataPath environment variable to th...HigLabo: HigLabo_20120613: Bug fix HigLabo.Mail Decode header encoded by CP1252Jasc (just another script compressor): 1.3.1: Updated Ajax Minifier to 4.55.WipeTouch, a jQuery touch plugin: 1.2.0: Changes since 1.1.0: New: wipeMove event, triggered while moving the mouse/finger. New: added "source" to the result object. Bug fix: sometimes vertical wipe events would not trigger correctly. Bug fix: improved tapToClick handler. General code refactoring. Windows Phone 7 is not supported, yet! Its behaviour is completely broken and would require some special tricks to make it work. Maybe in the future...Phalanger - The PHP Language Compiler for the .NET Framework: 3.0.0.3026 (June 2012): Fixes: round( 0.0 ) local TimeZone name TimeZone search compiling multi-script-assemblies PhpString serialization DocDocument::loadHTMLFile() token_get_all() parse_url()BlackJumboDog: Ver5.6.4: 2012.06.13 Ver5.6.4  (1) Web???????、???POST??????????????????Yahoo! UI Library: YUI Compressor for .Net: Version 2.0.0.0 - Ferret: - Merging both 3.5 and 2.0 codebases to a single .NET 2.0 assembly. - MSBuild Task. - NAnt Task.Bumblebee: Version 0.3.1: Changed default config values to decent ones. Restricted visibility of Hive.fs to internal. Added some XML documentation. Added Array.shuffle utility. The dll is also available on NuGet My apologies, the initial source code referenced was missing one file which prevented it from building The source code contains two examples, one in C#, one in F#, illustrating the usage of the framework on the Travelling Salesman Problem: Source CodeSharePoint XSL Templates: SPXSLT 0.0.9: Added new template FixAmpersands. Fixed the contents of the MultiSelectValueCheck.xsl file, which was missing the stylesheet wrapper.ExcelFileEditor: .CS File: nothingBizTalk Scheduled Task Adapter: Release 4.0: Works with BizTalk Server 2010. Compiled in .NET Framework 4.0. In this new version are available small improvements compared to the current version (3.0). We can highlight the following improvements or changes: 24 hours support in “start time” property. Previous versions had an issue with setting the start time, as it shown 12 hours watch but no AM/PM. Daily scheduler review. Solved a small bug on Daily Properties: unable to switch between “Every day” and “on these days” Installation e...Weapsy - ASP.NET MVC CMS: 1.0.0 RC: - Upgrade to Entity Framework 4.3.1 - Added AutoMapper custom version (by nopCommerce Team) - Added missed model properties and localization resources of Plugin Definitions - Minor changes - Fixed some bugsXenta Framework - extensible enterprise n-tier application framework: Xenta Framework 1.8.0 Beta: Catalog and Publication reviews and ratings Store language packs in data base Improve reporting system Improve Import/Export system A lot of WebAdmin app UI improvements Initial implementation of the WebForum app DB indexes Improve and simplify architecture Less abstractions Modernize architecture Improve, simplify and unify API Simplify and improve testing A lot of new unit tests Codebase refactoring and ReSharpering Utilize Castle Windsor Utilize NHibernate ORM ...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.55: Properly handle IE extension to CSS3 grammar that allows for multiple parameters to functional pseudo-class selectors. add new switch -braces:(new|same) that affects where opening braces are placed in multi-line output. The default, "new" puts them on their own new line; "same" outputs them at the end of the previous line. add new optional values to the -inline switch: -inline:(force|noforce), which can be combined with the existing boolean value via comma-separators; value "force" (which...Microsoft Media Platform: Player Framework: MMP Player Framework 2.7 (Silverlight and WP7): Additional DownloadsSMFv2.7 Full Installer (MSI) - This will install everything you need in order to develop your own SMF player application, including the IIS Smooth Streaming Client. It only includes the assemblies. If you want the source code please follow the link above. Smooth Streaming Sample Player - This is a pre-built player that includes support for IIS Smooth Streaming. You can configure the player to playback your content by simplying editing a configuration file - no need to co...Liberty: v3.2.1.0 Release 10th June 2012: Change Log -Added -Liberty is now digitally signed! If the certificate on Liberty.exe is missing, invalid, or does not state that it was developed by "Xbox Chaos, Open Source Developer," your copy of Liberty may have been altered in some (possibly malicious) way. -Reach Mass biped max health and shield changer -Fixed -H3/ODST Fixed all of the glitches that users kept reporting (also reverted the changes made in 3.2.0.2) -Reach Made some tag names clearer and more consistent between m...Media Companion: Media Companion 3.503b: It has been a while, so it's about time we release another build! Major effort has been for fixing trailer downloads, plus a little bit of work for episode guide tag in TV show NFOs.New Projects.NinJa (dotNinja): An extensive JavaScript Framework revolving around principles found in .NET and aiming to integrate full Intellisense support. bab-rizg: solve unemployment problemBizTalk Multi-part Message Attachments Zipper Pipeline Component: This pipeline component replaces all attachments of a multi-part message, in a send pipeline, for its zipped equivalent.Boggle.Net: A basic implementation of Boggle for WPF.CFScript: CFScript is an ANT-like scripting system for Compact Framework. Tasks like copying files, setting registry values o install CAB files can be done with CFScript.Diablo3: Diablo3Dygraphs.NET: Dygraphs.NETDynamics CRM plugin for nopCommerce: This plugins is a bridge between nopCommerce and Dynamics CRM. nms.gaming: Place holderProject Bright Star: Project Bright Star. Deal with it.RDFSharp: RDFSharp is a library designed to ease the development of .NET applications based on the RDF and Semantic Web data model.SlamCMS: An application framework that allows you to build content managed sites leveraging SharePoint 2010 for publishing with tools to query and manifest your data.test02: no

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  • Nginx Subdomain Problem

    - by user292299
    i can't access my subdomain on localhost. my localdomain is localhost.dev and it's work.but i want to auto subdomain for php script (username.localhost.dev) i try this server { listen 80 default_server; listen [::]:80 default_server ipv6only=on; access_log /var/www/access.log; error_log /var/www/error.log; root /var/www; index index.php index.html index.htm; # Make site accessible from http://localhost/ server_name localhost.dev ***.localhost.dev**; location / { # First attempt to serve request as file, then # as directory, then fall back to displaying a 404. try_files $uri $uri/ /index.html; # Uncomment to enable naxsi on this location # include /etc/nginx/naxsi.rules } location /f2/public/ { try_files $uri $uri/ /f2/public/index.php?$args; } location /doc/ { alias /usr/share/doc/; autoindex on; allow 127.0.0.1; allow ::1; deny all; } # Only for nginx-naxsi used with nginx-naxsi-ui : process denied requests #location /RequestDenied { # proxy_pass http://127.0.0.1:8080; #} #error_page 404 /404.html; # redirect server error pages to the static page /50x.html # #error_page 500 502 503 504 /50x.html; #location = /50x.html { # root /usr/share/nginx/html; #} # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000 # location ~ \.php$ { # fastcgi_split_path_info ^(.+\.php)(/.+)$; # # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini # # # With php5-cgi alone: # fastcgi_pass 127.0.0.1:9000; # # With php5-fpm: # fastcgi_pass unix:/var/run/php5-fpm.sock; # fastcgi_index index.php; # include fastcgi_params; include /etc/nginx/fastcgi_params; try_files $uri =404; fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; } # deny access to .htaccess files, if Apache's document root # concurs with nginx's one # #location ~ /\.ht { # deny all; #} } it's not working.i change server_name for testing server_name localhost.dev asd.localhost.dev; i can't access asd.localhost.dev and i try this double server{} section # You may add here your # server { # ... # } # statements for each of your virtual hosts to this file ## # You should look at the following URL's in order to grasp a solid understanding # of Nginx configuration files in order to fully unleash the power of Nginx. # http://wiki.nginx.org/Pitfalls # http://wiki.nginx.org/QuickStart # http://wiki.nginx.org/Configuration # # Generally, you will want to move this file somewhere, and start with a clean # file but keep this around for reference. Or just disable in sites-enabled. # # Please see /usr/share/doc/nginx-doc/examples/ for more detailed examples. ## server { listen 80 default_server; listen [::]:80 default_server ipv6only=on; access_log /var/www/access.log; error_log /var/www/error.log; root /var/www; index index.php index.html index.htm; # Make site accessible from http://localhost/ server_name localhost.dev; location / { # First attempt to serve request as file, then # as directory, then fall back to displaying a 404. try_files $uri $uri/ /index.html; # Uncomment to enable naxsi on this location # include /etc/nginx/naxsi.rules } location /f2/public/ { try_files $uri $uri/ /f2/public/index.php?$args; } location /doc/ { alias /usr/share/doc/; autoindex on; allow 127.0.0.1; allow ::1; deny all; } # Only for nginx-naxsi used with nginx-naxsi-ui : process denied requests #location /RequestDenied { # proxy_pass http://127.0.0.1:8080; #} #error_page 404 /404.html; # redirect server error pages to the static page /50x.html # #error_page 500 502 503 504 /50x.html; #location = /50x.html { # root /usr/share/nginx/html; #} # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000 # location ~ \.php$ { # fastcgi_split_path_info ^(.+\.php)(/.+)$; # # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini # # # With php5-cgi alone: # fastcgi_pass 127.0.0.1:9000; # # With php5-fpm: # fastcgi_pass unix:/var/run/php5-fpm.sock; # fastcgi_index index.php; # include fastcgi_params; include /etc/nginx/fastcgi_params; try_files $uri =404; fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; } # deny access to .htaccess files, if Apache's document root # concurs with nginx's one # #location ~ /\.ht { # deny all; #} } ############################### server { access_log /var/www/access.log; error_log /var/www/error.log; root /var/www; index index.php index.html index.htm; # Make site accessible from http://localhost/ server_name asd.localhost.dev; location / { # First attempt to serve request as file, then # as directory, then fall back to displaying a 404. try_files $uri $uri/ /index.html; # Uncomment to enable naxsi on this location # include /etc/nginx/naxsi.rules } location /f2/public/ { try_files $uri $uri/ /f2/public/index.php?$args; } location /doc/ { alias /usr/share/doc/; autoindex on; allow 127.0.0.1; allow ::1; deny all; } # Only for nginx-naxsi used with nginx-naxsi-ui : process denied requests #location /RequestDenied { # proxy_pass http://127.0.0.1:8080; #} #error_page 404 /404.html; # redirect server error pages to the static page /50x.html # #error_page 500 502 503 504 /50x.html; #location = /50x.html { # root /usr/share/nginx/html; #} # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000 # location ~ \.php$ { # fastcgi_split_path_info ^(.+\.php)(/.+)$; # # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini # # # With php5-cgi alone: # fastcgi_pass 127.0.0.1:9000; # # With php5-fpm: # fastcgi_pass unix:/var/run/php5-fpm.sock; # fastcgi_index index.php; # include fastcgi_params; include /etc/nginx/fastcgi_params; try_files $uri =404; fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; } # deny access to .htaccess files, if Apache's document root # concurs with nginx's one # #location ~ /\.ht { # deny all; #} } # another virtual host using mix of IP-, name-, and port-based configuration # #server { # listen 8000; # listen somename:8080; # server_name somename alias another.alias; # root html; # index index.html index.htm; # # location / { # try_files $uri $uri/ =404; # } #} # HTTPS server # #server { # listen 443; # server_name localhost; # # root html; # index index.html index.htm; # # ssl on; # ssl_certificate cert.pem; # ssl_certificate_key cert.key; # # ssl_session_timeout 5m; # # ssl_protocols SSLv3 TLSv1; # ssl_ciphers ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv3:+EXP; # ssl_prefer_server_ciphers on; # # location / { # try_files $uri $uri/ =404; # } #} i can't success

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  • PASS: The Budget Process

    - by Bill Graziano
    Every fiscal year PASS creates a detailed budget.  This helps us set priorities and communicate to our members what we’re going to do in the upcoming year.  You can review the current budget on the PASS Governance page.  That page currently requires you to login but I’m talking with HQ to see if there are any legal issues with opening that up. The Accounting Team The PASS accounting team is two people.  The Executive Vice-President of Finance (“EVP”) and the PASS Accounting Manager.  Sandy Cherry is the accounting manager and works at PASS HQ.  Sandy has been with PASS since we switched management companies in 2007.  Throughout this document when I talk about any actual work related to the budget that’s all Sandy :)  She’s the glue that gets us through this process.  Last year we went through 32 iterations of the budget before the Board approved so it’s a pretty busy time for her us – well, mostly her. Fiscal Year The PASS fiscal year runs from July 1st through June 30th the following year.  Right now we’re in fiscal year 2011.  Our 2010 Summit actually occurred in FY2011.  We switched to this schedule from a calendar year in 2006.  Our goal was to have the Summit occur early in our fiscal year.  That gives us the rest of the year to handle any significant financial impact from the Summit.  If registrations are down we can reduce spending.  If registrations are up we can decide how much to increase our reserves and how much to spend.  Keep in mind that the Summit is budgeted to generate 82% of our revenue this year.  How it performs has a significant impact on our financials.  The other benefit of this fiscal year is that it matches the Microsoft fiscal year.  We sign an annual sponsorship agreement with Microsoft and it’s very helpful that our fiscal years match. This year our budget process will probably start in earnest in March or April.  I’d like to be done in early June so we can publish before July 1st.  I was late publishing it this year and I’m trying not to repeat that. Our Budget Our actual budget is an Excel spreadsheet with 36 sheets.  We remove some of those when we publish it since they include salary information.  The budget is broken up into various portfolios or departments.  We have 20 portfolios.  They include chapters, marketing, virtual chapters, marketing, etc.  Ideally each portfolio is assigned to a Board member.  Each portfolio also typically has a staff person assigned to it.  Portfolios that aren’t assigned to a Board member are monitored by HQ and the ExecVP-Finance (me).  These are typically smaller portfolios such as deferred membership or Summit futures.  (More on those in a later post.)  All portfolios are reviewed by all Board members during the budget approval process, when interim financials are released internally and at year-end. The Process Our first step is to budget revenues.  The Board determines a target attendee number.  We have formulas based on historical performance that convert that to an overall attendee revenue number.  Other revenue projections (such as vendor sponsorships) come from different parts of the organization.  I hope to have another post with more details on how we project revenues. The next step is to budget expenses.  Board members fill out a sample spreadsheet with their budget for the year.  They can add line items and notes describing what the amounts are for.  Each Board portfolio typically has from 10 to 30 line items.  Any new initiatives they want to pursue needs to be budgeted.  The Summit operations budget is managed by HQ.  It includes the cost for food, electrical, internet, etc.  Most of these come from our estimate of attendees and our contract with the convention center.  During this process the Board can ask for more or less to be spent on various line items.  For example, if we weren’t happy with the Internet at the last Summit we can ask them to look into different options and/or increasing the budget.  HQ will also make adjustments to these numbers based on what they see at the events and the feedback we receive on the surveys. After we have all the initial estimates we start reviewing the entire budget.  It is sent out to the Board and we can see what each portfolio requested and what the overall profit and loss number is.  We usually start with too much in expenses and need to cut.  In years past the Board started haggling over these numbers as a group.  This past year they decided I should take a first cut and present them with a reasonable budget and a list of what I changed.  That worked well and I think we’ll continue to do that in the future. We go through a number of iterations on the budget.  If I remember correctly, we went through 32 iterations before we passed the budget.  At each iteration various revenue and expense numbers can change.  Keep in mind that the PASS budget has 200+ line items spread over 20 portfolios.  Many of these depend on other numbers.  For example, if we decide increase the projected attendees that cascades through our budget.  At each iteration we list what changed and the impact.  Ideally these discussions will take place at a face-to-face Board meeting.  Many of them also take place over the phone.  Board members explain any increase they are asking for while performing due diligence on other budget requests.  Eventually a budget emerges and is passed. Publishing After the budget is passed we create a version without the formulas and salaries for posting on the web site.  Sandy also creates some charts to help our members understand the budget.  The EVP writes a nice little letter describing some of the changes from last year’s budget.  You can see my letter and our budget on the PASS Governance page. And then, eight months later, we start all over again.

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  • Disaster, or Migration?

    - by Rob Farley
    This post is in two parts – technical and personal. And I should point out that it’s prompted in part by this month’s T-SQL Tuesday, hosted by Allen Kinsel. First, the technical: I’ve had a few conversations with people recently about migration – moving a SQL Server database from one box to another (sometimes, but not primarily, involving an upgrade). One question that tends to come up is that of downtime. Obviously there will be some period of time between the old server being available and the new one. The way that most people seem to think of migration is this: Build a new server. Stop people from using the old server. Take a backup of the old server Restore it on the new server. Reconfigure the client applications (or alternatively, configure the new server to use the same address as the old) Make the new server online. There are other things involved, such as testing, of course. But this is essentially the process that people tell me they’re planning to follow. The bit that I want to look at today (as you’ve probably guessed from my title) is the “backup and restore” section. If a SQL database is using the Simple Recovery Model, then the only restore option is the last database backup. This backup could be full or differential. The transaction log never gets backed up in the Simple Recovery Model. Instead, it truncates regularly to stay small. One that’s using the Full Recovery Model (or Bulk-Logged) won’t truncate its log – the log must be backed up regularly. This provides the benefit of having a lot more option available for restores. It’s a requirement for most systems of High Availability, because if you’re making sure that a spare box is up-and-running, ready to take over, then you have to be interested in the logs that are happening on the current box, rather than truncating them all the time. A High Availability system such as Mirroring, Replication or Log Shipping will initialise the spare machine by restoring a full database backup (and maybe a differential backup if available), and then any subsequent log backups. Once the secondary copy is close, transactions can be applied to keep the two in sync. The main aspect of any High Availability system is to have a redundant system that is ready to take over. So the similarity for migration should be obvious. If you need to move a database from one box to another, then introducing a High Availability mechanism can help. By turning on the Full Recovery Model and then taking a backup (so that the now-interesting logs have some context), logs start being kept, and are therefore available for getting the new box ready (even if it’s an upgraded version). When the migration is ready to occur, a failover can be done, letting the new server take over the responsibility of the old, just as if a disaster had happened. Except that this is a planned failover, not a disaster at all. There’s a fine line between a disaster and a migration. Failovers can be useful in patching, upgrading, maintenance, and more. Hopefully, even an unexpected disaster can be seen as just another failover, and there can be an opportunity there – perhaps to get some work done on the principal server to increase robustness. And if I’ve just set up a High Availability system for even the simplest of databases, it’s not necessarily a bad thing. :) So now the personal: It’s been an interesting time recently... June has been somewhat odd. A court case with which I was involved got resolved (through mediation). I can’t go into details, but my lawyers tell me that I’m allowed to say how I feel about it. The answer is ‘lousy’. I don’t regret pursuing it as long as I did – but in the end I had to make a decision regarding the commerciality of letting it continue, and I’m going to look forward to the days when the kind of money I spent on my lawyers is small change. Mind you, if I had a similar situation with an employer, I’d do the same again, but that doesn’t really stop me feeling frustrated about it. The following day I had to fly to country Victoria to see my grandmother, who wasn’t expected to last the weekend. She’s still around a week later as I write this, but her 92-year-old body has basically given up on her. She’s been a Christian all her life, and is looking forward to eternity. We’ll all miss her though, and it’s hard to see my family grieving. Then on Tuesday, I was driving back to the airport with my family to come home, when something really bizarre happened. We were travelling down the freeway, just pulled out to go past a truck (farm-truck sized, not a semi-trailer), when a car-sized mass of metal fell off it. It was something like an industrial air-conditioner, but from where I was sitting, it was just a mass of spinning metal, like something out of a movie (one friend described it as “holidays by Michael Bay”). Somehow, and I’m really don’t know how, the part of it nearest us bounced high enough to clear the car, and there wasn’t even a scratch. We pulled over the check, and I was just thanking God that we’d changed lanes when we had, and that we remained unharmed. I had all kinds of thoughts about what could’ve happened if we’d had something that size land on the windscreen... All this has drilled home that while I feel that I haven’t provided as well for the family as I could’ve done (like by pursuing an expensive legal case), I shouldn’t even consider that I have proper control over things. I get to live life, and make decisions based on what I feel is right at the time. But I’m not going to get everything right, and there will be things that feel like disasters, some which could’ve been in my control and some which are very much beyond my control. The case feels like something I could’ve pursued differently, a disaster that could’ve been avoided in some way. Gran dying is lousy of course. An accident on the freeway would have been awful. I need to recognise that the worst disasters are ones that I can’t affect, and that I need to look at things in context – perhaps seeing everything that happens as a migration instead. Life is never the same from one day to the next. Every event has a before and an after – sometimes it’s clearly positive, sometimes it’s not. I remember good events in my life (such as my wedding), and bad (such as the loss of my father when I was ten, or the back injury I had eight years ago). I’m not suggesting that I know how to view everything from the “God works all things for good” perspective, but I am trying to look at last week as a migration of sorts. Those things are behind me now, and the future is in God’s hands. Hopefully I’ve learned things, and will be able to live accordingly. I’ve come through this time now, and even though I’ll miss Gran, I’ll see her again one day, and the future is bright.

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  • Scheduling thread tiles with C++ AMP

    - by Daniel Moth
    This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

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  • General Policies and Procedures for Maintaining the Value of Data Assets

    Here is a general list for policies and procedures regarding maintaining the value of data assets. Data Backup Policies and Procedures Backups are very important when dealing with data because there is always the chance of losing data due to faulty hardware or a user activity. So the need for a strategic backup system should be mandatory for all companies. This being said, in the real world some companies that I have worked for do not really have a good data backup plan. Typically when companies tend to take this kind of approach in data backups usually the data is not really recoverable.  Unfortunately when companies do not regularly test their backup plans they get a false sense of security because they think that they are covered. However, I can tell you from personal and professional experience that a backup plan/system is never fully implemented until it is regularly tested prior to the time when it actually needs to be used. Disaster Recovery Plan Expanding on Backup Policies and Procedures, a company needs to also have a disaster recovery plan in order to protect its data in case of a catastrophic disaster.  Disaster recovery plans typically encompass how to restore all of a company’s data and infrastructure back to a restored operational status.  Most Disaster recovery plans also include time estimates on how long each step of the disaster recovery plan should take to be executed.  It is important to note that disaster recovery plans are never fully implemented until they have been tested just like backup plans. Disaster recovery plans should be tested regularly so that the business can be confident in not losing any or minimal data due to a catastrophic disaster. Firewall Policies and Content Filters One way companies can protect their data is by using a firewall to separate their internal network from the outside. Firewalls allow for enabling or disabling network access as data passes through it by applying various defined restrictions. Furthermore firewalls can also be used to prevent access from the internal network to the outside by these same factors. Common Firewall Restrictions Destination/Sender IP Address Destination/Sender Host Names Domain Names Network Ports Companies can also desire to restrict what their network user’s view on the internet through things like content filters. Content filters allow a company to track what webpages a person has accessed and can also restrict user’s access based on established rules set up in the content filter. This device and/or software can block access to domains or specific URLs based on a few factors. Common Content Filter Criteria Known malicious sites Specific Page Content Page Content Theme  Anti-Virus/Mal-ware Polices Fortunately, most companies utilize antivirus programs on all computers and servers for good reason, virus have been known to do the following: Corrupt/Invalidate Data, Destroy Data, and Steal Data. Anti-Virus applications are a great way to prevent any malicious application from being able to gain access to a company’s data.  However, anti-virus programs must be constantly updated because new viruses are always being created, and the anti-virus vendors need to distribute updates to their applications so that they can catch and remove them. Data Validation Policies and Procedures Data validation is very important to ensure that only accurate information is stored. The existence of invalid data can cause major problems when businesses attempt to use data for knowledge based decisions and for performance reporting. Data Scrubbing Policies and Procedures Data scrubbing is valuable to companies in one of two ways. The first can be used to clean data prior to being analyzed for report generation. The second is that it allows companies to remove things like personally Identifiable information from its data prior to transmit it between multiple environments or if the information is sent to an external location. An example of this can be seen with medical records in regards to HIPPA laws that prohibit the storage of specific personal and medical information. Additionally, I have professionally run in to a scenario where the Canadian government does not allow any Canadian’s personal information to be stored on a server not located in Canada. Encryption Practices The use of encryption is very valuable when a company needs to any personal information. This allows users with the appropriated access levels to view or confirm the existence or accuracy of data within a system by either decrypting the information or encrypting a piece of data and comparing it to the stored version.  Additionally, if for some unforeseen reason the data got in to the wrong hands then they would have to first decrypt the data before they could even be able to read it. Encryption just adds and additional layer of protection around data itself. Standard Normalization Practices The use of standard data normalization practices is very important when dealing with data because it can prevent allot of potential issues by eliminating the potential for unnecessary data duplication. Issues caused by data duplication include excess use of data storage, increased chance for invalidated data, and over use of data processing. Network and Database Security/Access Policies Every company has some form of network/data access policy even if they have none. These policies help secure data from being seen by inappropriate users along with preventing the data from being updated or deleted by users. In addition, without a good security policy there is a large potential for data to be corrupted by unassuming users or even stolen. Data Storage Policies Data storage polices are very important depending on how they are implemented especially when a company is trying to utilize them in conjunction with other policies like Data Backups. I have worked at companies where all network user folders are constantly backed up, and if a user wanted to ensure the existence of a piece of data in the form of a file then they had to store that file in their network folder. Conversely, I have also worked in places where when a user logs on or off of the network there entire user profile is backed up. Training Policies One of the biggest ways to prevent data loss and ensure that data will remain a company asset is through training. The practice of properly train employees on how to work with in systems that access data is crucial when trying to ensure a company’s data will remain an asset. Users need to be trained on how to manipulate a company’s data in order to perform their tasks to reduce the chances of invalidating data.

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