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  • Extending ASP.NET Output Caching

    One of the most sure-fire ways to improve a web application's performance is to employ caching. Caching takes some expensive operation and stores its results in a quickly accessible location. Since it's inception, ASP.NET has offered two flavors of caching:<ul><li><b>Output Caching</b> - caches the entire rendered markup of an ASP.NET page or <a href="http://www.asp101.com/lessons/usercontrols.asp">User Control</a> for a specified duration.</li><li><b>Data Caching</b> - a API for caching objects. Using the data cache you can write code to add, remove, and retrieve items from the cache.</li></ul>Until recently, the underlying functionality of these two caching mechanisms was fixed - both cached data

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  • SQL SERVER – Guest Post by Sandip Pani – SQL Server Statistics Name and Index Creation

    - by pinaldave
    Sometimes something very small or a common error which we observe in daily life teaches us new things. SQL Server Expert Sandip Pani (winner of Joes 2 Pros Contests) has come across similar experience. Sandip has written a guest post on an error he faced in his daily work. Sandip is working for QSI Healthcare as an Associate Technical Specialist and have more than 5 years of total experience. He blogs at SQLcommitted.com and contribute in various forums. His social media hands are LinkedIn, Facebook and Twitter. Once I faced following error when I was working on performance tuning project and attempt to create an Index. Mug 1913, Level 16, State 1, Line 1 The operation failed because an index or statistics with name ‘Ix_Table1_1′ already exists on table ‘Table1′. The immediate reaction to the error was that I might have created that index earlier and when I researched it further I found the same as the index was indeed created two times. This totally makes sense. This can happen due to many reasons for example if the user is careless and executes the same code two times as well, when he attempts to create index without checking if there was index already on the object. However when I paid attention to the details of the error, I realize that error message also talks about statistics along with the index. I got curious if the same would happen if I attempt to create indexes with the same name as statistics already created. There are a few other questions also prompted in my mind. I decided to do a small demonstration of the subject and build following demonstration script. The goal of my experiment is to find out the relation between statistics and the index. Statistics is one of the important input parameter for the optimizer during query optimization process. If the query is nontrivial then only optimizer uses statistics to perform a cost based optimization to select a plan. For accuracy and further learning I suggest to read MSDN. Now let’s find out the relationship between index and statistics. We will do the experiment in two parts. i) Creating Index ii) Creating Statistics We will be using the following T-SQL script for our example. IF (OBJECT_ID('Table1') IS NOT NULL) DROP TABLE Table1 GO CREATE TABLE Table1 (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO We will be using following two queries to check if there are any index or statistics on our sample table Table1. -- Details of Index SELECT OBJECT_NAME(OBJECT_ID) AS TableName, Name AS IndexName, type_desc FROM sys.indexes WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO -- Details of Statistics SELECT OBJECT_NAME(OBJECT_ID) TableName, Name AS StatisticsName FROM sys.stats WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO When I ran above two scripts on the table right after it was created it did not give us any result which was expected. Now let us begin our test. 1) Create an index on the table Create following index on the table. CREATE NONCLUSTERED INDEX Ix_Table1_1 ON Table1(Col1) GO Now let us use above two scripts and see their results. We can see that when we created index at the same time it created statistics also with the same name. Before continuing to next set of demo – drop the table using following script and re-create the table using a script provided at the beginning of the table. DROP TABLE table1 GO 2) Create a statistic on the table Create following statistics on the table. CREATE STATISTICS Ix_table1_1 ON Table1 (Col1) GO Now let us use above two scripts and see their results. We can see that when we created statistics Index is not created. The behavior of this experiment is different from the earlier experiment. Clean up the table setup using the following script: DROP TABLE table1 GO Above two experiments teach us very valuable lesson that when we create indexes, SQL Server generates the index and statistics (with the same name as the index name) together. Now due to the reason if we have already had statistics with the same name but not the index, it is quite possible that we will face the error to create the index even though there is no index with the same name. A Quick Check To validate that if we create statistics first and then index after that with the same name, it will throw an error let us run following script in SSMS. Make sure to drop the table and clean up our sample table at the end of the experiment. -- Create sample table CREATE TABLE TestTable (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO -- Create Statistics CREATE STATISTICS IX_TestTable_1 ON TestTable (Col1) GO -- Create Index CREATE NONCLUSTERED INDEX IX_TestTable_1 ON TestTable(Col1) GO -- Check error /*Msg 1913, Level 16, State 1, Line 2 The operation failed because an index or statistics with name 'IX_TestTable_1' already exists on table 'TestTable'. */ -- Clean up DROP TABLE TestTable GO While creating index it will throw the following error as statistics with the same name is already created. In simple words – when we create index the name of the index should be different from any of the existing indexes and statistics. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Statistics

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  • Windows Azure Use Case: Hybrid Applications

    - by BuckWoody
    This is one in a series of posts on when and where to use a distributed architecture design in your organization's computing needs. You can find the main post here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx  Description: Organizations see the need for computing infrastructures that they can “rent” or pay for only when they need them. They also understand the benefits of distributed computing, but do not want to create this infrastructure themselves. However, they may have considerations that prevent them from moving all of their current IT investment to a distributed environment: Private data (do not want to send or store sensitive data off-site) High dollar investment in current infrastructure Applications currently running well, but may need additional periodic capacity Current applications not designed in a stateless fashion In these situations, a “hybrid” approach works best. In fact, with Windows Azure, a hybrid approach is an optimal way to implement distributed computing even when the stipulations above do not apply. Keeping a majority of the computing function in an organization local while exploring and expanding that footprint into Windows and SQL Azure is a good migration or expansion strategy. A “hybrid” architecture merely means that part of a computing cycle is shared between two architectures. For instance, some level of computing might be done in a Windows Azure web-based application, while the data is stored locally at the organization. Implementation: There are multiple methods for implementing a hybrid architecture, in a spectrum from very little interaction from the local infrastructure to Windows or SQL Azure. The patterns fall into two broad schemas, and even these can be mixed. 1. Client-Centric Hybrid Patterns In this pattern, programs are coded such that the client system sends queries or compute requests to multiple systems. The “client” in this case might be a web-based codeset actually stored on another system (which acts as a client, the user’s device serving as the presentation layer) or a compiled program. In either case, the code on the client requestor carries the burden of defining the layout of the requests. While this pattern is often the easiest to code, it’s the most brittle. Any change in the architecture must be reflected on each client, but this can be mitigated by using a centralized system as the client such as in the web scenario. 2. System-Centric Hybrid Patterns Another approach is to create a distributed architecture by turning on-site systems into “services” that can be called from Windows Azure using the service Bus or the Access Control Services (ACS) capabilities. Code calls from a series of in-process client application. In this pattern you move the “client” interface into the server application logic. If you do not wish to change the application itself, you can “layer” the results of the code return using a product (such as Microsoft BizTalk) that exposes a Web Services Definition Language (WSDL) endpoint to Windows Azure using the Application Fabric. In effect, this is similar to creating a Service Oriented Architecture (SOA) environment, and has the advantage of de-coupling your computing architecture. If each system offers a “service” of the results of some software processing, the operating system or platform becomes immaterial, assuming it adheres to a service contract. There are important considerations when you federate a system, whether to Windows or SQL Azure or any other distributed architecture. While these considerations are consistent with coding any application for distributed computing, they are especially important for a hybrid application. Connection resiliency - Applications on-premise normally have low-latency and good connection properties, something you’re not always guaranteed in a distributed and hybrid application. Whether a centralized client or a distributed one, the code should be able to handle extended retry logic. Authorization and Access - In a single authorization environment like a Active Directory domain, security is handled at a user-password level. In a distributed computing environment, you have more options. You can mitigate this with  using The Windows Azure Application Fabric feature of ACS to make the Azure application aware of the App Fabric as an ADFS provider. However, a claims-based authentication structure is often a superior choice.  Consistency and Concurrency - When you have a Relational Database Management System (RDBMS), Consistency and Concurrency are part of the design. In a Service Architecture, you need to plan for sequential message handling and lifecycle. Resources: How to Build a Hybrid On-Premise/In Cloud Application: http://blogs.msdn.com/b/ignitionshowcase/archive/2010/11/09/how-to-build-a-hybrid-on-premise-in-cloud-application.aspx  General Architecture guidance: http://blogs.msdn.com/b/buckwoody/archive/2010/12/21/windows-azure-learning-plan-architecture.aspx   

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  • How can Swift be so much faster than Objective-C in these comparisons?

    - by Yellow
    Apple launched its new programming language Swift at WWDC14. In the presentation, they made some performance comparisons between Objective-C and Python. The following is a picture of one of their slides, of a comparison of those three languages performing some complex object sort: There was an even more incredible graph about a performance comparison using the RC4 encryption algorithm. Obviously this is a marketing talk, and they didn't go into detail on how this was implemented in each. I leaves me wondering though: How can a new programming language be so much faster? Are the Objective-C results caused by a bad compiler or is there something less efficient in Objective-C than Swift? How would you explain a 40% performance increase? I understand that garbage collection/automated reference control might produce some additional overhead, but this much?

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  • How To Disable the Amazon Search Ads in Ubuntu’s Unity Dash

    - by Chris Hoffman
    Upgrade to Ubuntu 12.10 (Quantal Quetzal) and you’ll run into a surprise – Ubuntu now shows you advertisements for Amazon products when you search in your dash. There’s also an Amazon shortcut pinned to Unity’s launcher. There are several ways to disable these ads, and they aren’t immediately obvious. However, you can easily disable the Amazon search results if you don’t want to see them, or if you’re concerned about the privacy implications. What To Do If You Get a Virus on Your Computer Why Enabling “Do Not Track” Doesn’t Stop You From Being Tracked HTG Explains: What is the Windows Page File and Should You Disable It?

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  • SQLBits - Unicode Porn

    - by Most Valuable Yak (Rob Volk)
    We've just finished up a fantastic event at SQLBits X in London!  If you've never been to SQLBits and you can make it to the UK, I highly recommend it.  If you didn't attend, here's what you missed. Meanwhile, for those who attended the Lightning Talk sessions and were disappointed that I ran out of time, here's the last part that you would have seen: /*    How to Lose Friends and Irritate People...With Unicode!     Rob Volk     SQLBits X - London - March 31, 2012 */ -- some sexy SQL DECLARE @oohbaby TABLE(i INT NOT NULL UNIQUE, uni_char AS NCHAR(i), hex AS CAST(i AS BINARY(2))) INSERT @oohbaby VALUES(664),(1022),(1023),(1120),(1150),(8857),(11609),(42420),(42427) -- change results font to larger size, some only work in grid font SELECT * FROM @oohbaby SELECT NCHAR(1022) + NCHAR(1023) AS Page3Girl It's probably better that you run this yourself, in the privacy of your own home/office, you know *wink* *wink* *nudge* *nudge* *say no more*

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  • How to find domain registrar and DNS hosting with good DNSSEC support?

    - by rsp
    Simplified problem I want to buy a domain and make a website that is fully secured with DNSSEC. Background I've been hearing about the insecurity of DNS for years. I've watched all of the talks by Dan Kaminsky and others from DNS exploits to The future of DNS Security Panel. I knew that using DNS without security is a disaster waiting to happen. I followed the development of the DNSSEC standard. I celebrated the key signing ceremony. Everything was on the right track to finally have a secure DNS system in place. And now more than 2 years later I wanted to just do what everyone said I should do: use DNSSEC for a new domain. So I need a domain registrar and a DNS hosting service that supports DNSSEC. Surprisingly it is not that easy to even find out who does support DNSSEC. It was actually much easier to find info on DNSSEC two years ago when everyone was going to support DNSSEC Real Soon Now but now years passed and I hardly see any progress done. I just hope that I was just looking in the wrong places and someone here will explain all of the doubts. I hope that other people who want to have a secure website will also find this question useful. What is needed registrar and DNS servers with full DNSSEC support for .com domains What is not needed IPv6 support Web hosting anything more What I found out so far Go Daddy offers Premium DNS service for additional $36 per year that lets you "Secure up to 5 domains with DNSSEC". easyDNS has DNSSEC available in Beta across all service levels (you need to enable the "beta" flag in configuration) but it doesn't seem to be production ready and judging from the lack of updates it isn't a feature of highest priority (the last update from March 2011 on the easyDNS blog). Name.com - according to The Register (US domain registrar does IPv6, DNSSEC) it has DNSSEC support since 2010 but right now (October 2012) I couldn't find anything related to DNSSEC on their website. Dynadot that is very often recommended doesn't support DNSSEC Namecheap that is also often recommended doesn't support DNSSEC. The support answer from 2011 suggested that it was being added but in 2012 still no ETA is given to customers. DynDNS was supposed to support DNSSEC, I found a link explaining DNSSEC support but it gives 404 Not Found page and offers a search box - when searching for DNSSEC I get "No results were found for your query." GKG was recommended online for DNSSEC support but it's hard to find any information on the level of DNSSEC support - there is a brief explanation on what is DNSSEC and how to sign Delegation Signer records in their FAQ but no information about the level of actual support can be found. Ask Slashdot: Which Registrars Support DNSSEC? from July 2011 - Answers list Go Daddy, DynDNS, GKG, Name.com as registrars that support DNSSEC but: see above. Related questions How to find web hosting that meets my requirements? What is needed to add DNSSEC to my site? DNS hosting better managed by Domain provider or Hosting provider? Registrar with good security, DNS hosting, and DNSSEC and IPv6 resolvers? In no. 1 no one is ever mentioning DNS at all. In no. 2 answers only mention the .se TLD, there are very few answers and they seem very outdated. In no. 3 one answer says "On projects that demand higher security, I might look for a web host that supports DNSSEC" but no more information is provided. The only relevant answers are in no. 4 where easyDNS is recommended by someone who has never used them personally. Meanwhile, as of October 2012, the support of DNSSEC is described as "in beta" on the easyDNS feature list. Another one recommends SiteGround but searching their site for DNSSEC returns no results. Other answers recommend web hosting providers that don't meet the requirement of DNSSEC support. Also the question mentioned above lists 9 very specific requirements other than only DNSSEC (like eg. HTTP-only login cookies, two-factor authentications, no DNS record limits, DNS statistics of queries/day, audit trails etc.) which might have excluded many possible recommendations if one is only interested in DNSSEC support. Conclusions I thought that by the end of 2012 the support of DNSSEC among domain registrars and DNS providers would be nearly universal. I am shocked that the support seems virtually nonexistent. Is this a result of some serious problems with the DNSSEC adoption? Or is it just not a hot topic and no one bothers anymore? According to the DNSSEC Scoreboard roughly about 0.1% of .com domains support DNSSEC. Could that be caused by the lack of DNSSEC support among registrars and DNS providers, is the information too hard to find or maybe no one cares? There is even no "dnssec" tag here. Questions The information is surprisingly hard to find. That is why I am asking for first-hand experience and personal recommendations. Has anyone here actually set up a website with DNSSEC, from the domain registration to the configuration of DNS servers? Can anyone recommend any of the registrars mentioned above? Can anyone recommend any registrar not mentioned above?

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  • Connecting to Magento Web Services with Java

    - by kerry
    I was in the unenviable position of needing to connect to Magento, a PHP ecommerce platform, web services using Java.  It was kind of difficult to get the classes generated from the WSDL so I figured I would throw the results up on my github account for any other poor sap in a similar position. First, pull down the project using git: git clone git://github.com/webdevwilson/magento-java.git and build it with maven: mvn install Here is a quick example of how to pull an order using the generated classes: MagentoServiceLocator serviceLocator = new MagentoServiceLocator(); String url = "http://domain.com/index.php/api/v2_soap"; Mage_Api_Model_Server_V2_HandlerPortType port = serviceLocator.getMage_Api_Model_Server_V2_HandlerPort(url); String sessionId = port.login("username", "key"); SalesOrderEntity salesOrder = port.salesOrderInfo(sessionId, orderId); I also have some wrapper code in there that makes it a little easier to call the API. Checkout the project at https://github.com/webdevwilson/magento-java There is another option. it’s called Magja and it is located at google code.

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  • Are there real world applications where the use of prefix versus postfix operators matters?

    - by Kenneth
    In college it is taught how you can do math problems which use the ++ or -- operators on some variable referenced in the equation such that the result of the equation would yield different results if you switched the operator from postfix to prefix or vice versa. Are there any real world applications of using postfix or prefix operator where it makes a difference as to which you use? It doesn't seem to me (maybe I just don't have enough experience yet in programming) that there really is much use to having the different operators if it only applies in math equations. EDIT: Suggestions so far include: function calls //f(++x) != f(x++) loop comparison //while (++i < MAX) != while (i++ < MAX)

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  • MySQL Query Cache

    - by BRADINO
    According to MySQL.com the query cache stores the text of a SELECT statement together with the corresponding result that was sent to the client. If an identical statement is received later, the server retrieves the results from the query cache rather than parsing and executing the statement again. The query cache is shared among sessions, so a result set generated by one client can be sent in response to the same query issued by another client. Purely hypothetical example: SELECT `name` FROM `beers` WHERE `favorite` = true To force the database NOT to give you a cached result simply add SQL_NO_CACHE to the query: SELECT SQL_NO_CACHE `name` FROM `beers` WHERE `favorite` = true mysql query cache sql no cache mysql nocache

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  • HTTP Basic Auth Protected Services using Web Service Data Control

    - by vishal.s.jain(at)oracle.com
    With Oracle JDeveloper 11g (11.1.1.4.0) one can now create Web Service Data Control for services which are protected with HTTP Basic Authentication.So when you provide such a service to the Data Control Wizard, a dialog pops up prompting you to entry the authentication details:After you give the details, you can proceed with the creation of Data Control.Once the Data Control is created, you can use the WSDC Tester to quickly test the service.In this case, since the service is protected, we need to first edit the connection to provide username details:Enter the authentication details against username and password. Once done, select DataControl.dcx and using the context menu, select 'Run'. This will bring up the Tester.On the Tester, select the Service Node and using context menu pick 'Operations'. This will bring up the methods which you can test:Now you can pick a method, provide the input parameters and hit execute to see the results.

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  • How do I draw a border around a display object in Corona Lua?

    - by Greg
    What would be the easiest way to draw a thin border around a display object in Corona Lua? You could assume it's rectangular image display object. EDIT - re "this question shows no research effort. You should tell us what you've tried and how it didn't work" Reviewed API and could not find a "border" method/property on displayObject Have tried creating a black box slightly bigger behind object, however can not see how to place object behind an existing object hence question How do I move an existing display object behind another in Corona Lua? Google results for putting a border around a display object in corona didn't help

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  • Tokenizing JavaScript: A look at what’s left after minification

    - by InfinitiesLoop
    Minifiers JavaScript minifiers are popular these days. Closure , YUI Compressor , Microsoft Ajax Minifier , to name a few. Using one is essential for any site that uses more than a little script and cares about performance. Each tool of course has advantages and disadvantages. But they all do a pretty good job. The results vary only slightly in the grand scheme of things. Not enough to make so much of a difference that I’d say you should always use one over the other – use whatever fits in with your...(read more)

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  • AWS: setting up auto-scale for EC2 instances

    - by Elton Stoneman
    Originally posted on: http://geekswithblogs.net/EltonStoneman/archive/2013/10/16/aws-setting-up-auto-scale-for-ec2-instances.aspxWith Amazon Web Services, there’s no direct equivalent to Azure Worker Roles – no Elastic Beanstalk-style application for .NET background workers. But you can get the auto-scale part by configuring an auto-scaling group for your EC2 instance. This is a step-by-step guide, that shows you how to create the auto-scaling configuration, which for EC2 you need to do with the command line, and then link your scaling policies to CloudWatch alarms in the Web console. I’m using queue size as my metric for CloudWatch,  which is a good fit if your background workers are pulling messages from a queue and processing them.  If the queue is getting too big, the “high” alarm will fire and spin up a new instance to share the workload. If the queue is draining down, the “low” alarm will fire and shut down one of the instances. To start with, you need to manually set up your app in an EC2 VM, for a background worker that would mean hosting your code in a Windows Service (I always use Topshelf). If you’re dual-running Azure and AWS, then you can isolate your logic in one library, with a generic entry point that has Start() and Stop()  functions, so your Worker Role and Windows Service are essentially using the same code. When you have your instance set up with the Windows Service running automatically, and you’ve tested it starts up and works properly from a reboot, shut the machine down and take an image of the VM, using Create Image (EBS AMI) from the Web Console: When that completes, you’ll have your own AMI which you can use to spin up new instances, and you’re ready to create your auto-scaling group. You need to dip into the command-line tools for this, so follow this guide to set up the AWS autoscale command line tool. Now we’re ready to go. 1. Create a launch configuration This launch configuration tells AWS what to do when a new instance needs to be spun up. You create it with the as-create-launch-config command, which looks like this: as-create-launch-config sc-xyz-launcher # name of the launch config --image-id ami-7b9e9f12 # id of the AMI you extracted from your VM --region eu-west-1 # which region the new instance gets created in --instance-type t1.micro # size of the instance to create --group quicklaunch-1 #security group for the new instance 2. Create an auto-scaling group The auto-scaling group links to the launch config, and defines the overall configuration of the collection of instances: as-create-auto-scaling-group sc-xyz-asg # auto-scaling group name --region eu-west-1 # region to create in --launch-configuration sc-xyz-launcher # name of the launch config to invoke for new instances --min-size 1 # minimum number of nodes in the group --max-size 5 # maximum number of nodes in the group --default-cooldown 300 # period to wait (in seconds) after each scaling event, before checking if another scaling event is required --availability-zones eu-west-1a eu-west-1b eu-west-1c # which availability zones you want your instances to be allocated in – multiple entries means EC@ will use any of them 3. Create a scale-up policy The policy dictates what will happen in response to a scaling event being triggered from a “high” alarm being breached. It links to the auto-scaling group; this sample results in one additional node being spun up: as-put-scaling-policy scale-up-policy # policy name -g sc-psod-woker-asg # auto-scaling group the policy works with --adjustment 1 # size of the adjustment --region eu-west-1 # region --type ChangeInCapacity # type of adjustment, this specifies a fixed number of nodes, but you can use PercentChangeInCapacity to make an adjustment relative to the current number of nodes, e.g. increasing by 50% 4. Create a scale-down policy The policy dictates what will happen in response to a scaling event being triggered from a “low” alarm being breached. It links to the auto-scaling group; this sample results in one node from the group being taken offline: as-put-scaling-policy scale-down-policy -g sc-psod-woker-asg "--adjustment=-1" # in Windows, use double-quotes to surround a negative adjustment value –-type ChangeInCapacity --region eu-west-1 5. Create a “high” CloudWatch alarm We’re done with the command line now. In the Web Console, open up the CloudWatch view and create a new alarm. This alarm will monitor your metrics and invoke the scale-up policy from your auto-scaling group, when the group is working too hard. Configure your metric – this example will fire the alarm if there are more than 10 messages in my queue for over a minute: Then link the alarm to the scale-up policy in your group: 6. Create a “low” CloudWatch alarm The opposite of step 4, this alarm will trigger when the instances in your group don’t have enough work to do (e.g fewer than 2 messages in the queue for 1 minute), and will invoke the scale-down policy. And that’s it. You don’t need your original VM as the auto-scale group has a minimum number of nodes connected. You can test out the scaling by flexing your CloudWatch metric – in this example, filling up a queue from a  stub publisher – and watching AWS create new nodes as required, then stopping the publisher and watch AWS kill off the spare nodes.

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  • SQL SERVER – Parsing SSIS Catalog Messages – Notes from the Field #030

    - by Pinal Dave
    [Note from Pinal]: This is a new episode of Notes from the Field series. SQL Server Integration Service (SSIS) is one of the most key essential part of the entire Business Intelligence (BI) story. It is a platform for data integration and workflow applications. The tool may also be used to automate maintenance of SQL Server databases and updates to multidimensional cube data. In this episode of the Notes from the Field series I requested SSIS Expert Andy Leonard to discuss one of the most interesting concepts of SSIS Catalog Messages. There are plenty of interesting and useful information captured in the SSIS catalog and we will learn together how to explore the same. The SSIS Catalog captures a lot of cool information by default. Here’s a query I use to parse messages from the catalog.operation_messages table in the SSISDB database, where the logged messages are stored. This query is set up to parse a default message transmitted by the Lookup Transformation. It’s one of my favorite messages in the SSIS log because it gives me excellent information when I’m tuning SSIS data flows. The message reads similar to: Data Flow Task:Information: The Lookup processed 4485 rows in the cache. The processing time was 0.015 seconds. The cache used 1376895 bytes of memory. The query: USE SSISDB GO DECLARE @MessageSourceType INT = 60 DECLARE @StartOfIDString VARCHAR(100) = 'The Lookup processed ' DECLARE @ProcessingTimeString VARCHAR(100) = 'The processing time was ' DECLARE @CacheUsedString VARCHAR(100) = 'The cache used ' DECLARE @StartOfIDSearchString VARCHAR(100) = '%' + @StartOfIDString + '%' DECLARE @ProcessingTimeSearchString VARCHAR(100) = '%' + @ProcessingTimeString + '%' DECLARE @CacheUsedSearchString VARCHAR(100) = '%' + @CacheUsedString + '%' SELECT operation_id , SUBSTRING(MESSAGE, (PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1)) - (PATINDEX(@StartOfIDSearchString, MESSAGE) + LEN(@StartOfIDString) + 1))) AS LookupRowsCount , SUBSTRING(MESSAGE, (PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1)) - (PATINDEX(@ProcessingTimeSearchString, MESSAGE) + LEN(@ProcessingTimeString) + 1))) AS LookupProcessingTime , CASE WHEN (CONVERT(numeric(3,3),SUBSTRING(MESSAGE, (PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1)) - (PATINDEX(@ProcessingTimeSearchString, MESSAGE) + LEN(@ProcessingTimeString) + 1))))) = 0 THEN 0 ELSE CONVERT(bigint,SUBSTRING(MESSAGE, (PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1)) - (PATINDEX(@StartOfIDSearchString, MESSAGE) + LEN(@StartOfIDString) + 1)))) / CONVERT(numeric(3,3),SUBSTRING(MESSAGE, (PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@ProcessingTimeSearchString,MESSAGE) + LEN(@ProcessingTimeString) + 1)) - (PATINDEX(@ProcessingTimeSearchString, MESSAGE) + LEN(@ProcessingTimeString) + 1)))) END AS LookupRowsPerSecond , SUBSTRING(MESSAGE, (PATINDEX(@CacheUsedSearchString,MESSAGE) + LEN(@CacheUsedString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@CacheUsedSearchString,MESSAGE) + LEN(@CacheUsedString) + 1)) - (PATINDEX(@CacheUsedSearchString, MESSAGE) + LEN(@CacheUsedString) + 1))) AS LookupBytesUsed ,CASE WHEN (CONVERT(bigint,SUBSTRING(MESSAGE, (PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1)) - (PATINDEX(@StartOfIDSearchString, MESSAGE) + LEN(@StartOfIDString) + 1)))))= 0 THEN 0 ELSE CONVERT(bigint,SUBSTRING(MESSAGE, (PATINDEX(@CacheUsedSearchString,MESSAGE) + LEN(@CacheUsedString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@CacheUsedSearchString,MESSAGE) + LEN(@CacheUsedString) + 1)) - (PATINDEX(@CacheUsedSearchString, MESSAGE) + LEN(@CacheUsedString) + 1)))) / CONVERT(bigint,SUBSTRING(MESSAGE, (PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1), ((CHARINDEX(' ', MESSAGE, PATINDEX(@StartOfIDSearchString,MESSAGE) + LEN(@StartOfIDString) + 1)) - (PATINDEX(@StartOfIDSearchString, MESSAGE) + LEN(@StartOfIDString) + 1)))) END AS LookupBytesPerRow FROM [catalog].[operation_messages] WHERE message_source_type = @MessageSourceType AND MESSAGE LIKE @StartOfIDSearchString GO Note that you have to set some parameter values: @MessageSourceType [int] – represents the message source type value from the following results: Value     Description 10           Entry APIs, such as T-SQL and CLR Stored procedures 20           External process used to run package (ISServerExec.exe) 30           Package-level objects 40           Control Flow tasks 50           Control Flow containers 60           Data Flow task 70           Custom execution message Note: Taken from Reza Rad’s (excellent!) helper.MessageSourceType table found here. @StartOfIDString [VarChar(100)] – use this to uniquely identify the message field value you wish to parse. In this case, the string ‘The Lookup processed ‘ identifies all the Lookup Transformation messages I desire to parse. @ProcessingTimeString [VarChar(100)] – this parameter is message-specific. I use this parameter to specifically search the message field value for the beginning of the Lookup Processing Time value. For this execution, I use the string ‘The processing time was ‘. @CacheUsedString [VarChar(100)] – this parameter is also message-specific. I use this parameter to specifically search the message field value for the beginning of the Lookup Cache  Used value. It returns the memory used, in bytes. For this execution, I use the string ‘The cache used ‘. The other parameters are built from variations of the parameters listed above. The query parses the values into text. The string values are converted to numeric values for ratio calculations; LookupRowsPerSecond and LookupBytesPerRow. Since ratios involve division, CASE statements check for denominators that equal 0. Here are the results in an SSMS grid: This is not the only way to retrieve this information. And much of the code lends itself to conversion to functions. If there is interest, I will share the functions in an upcoming post. If you want to get started with SSIS with the help of experts, read more over at Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: SSIS

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  • System reverts to 87Hz refresh rate at every startup after I have installed nvidia drivers

    - by Mohammad Kamil Nadeem
    Every time the system starts the screen's refresh rate reverts to 87Hz which results in a pixelated and flickery screen which I have to manually correct every time by either selecting 60Hz as my refresh rate. I have tried "save to X configuration files" and even tried by making the changes as Root but to no avail as it again reverts to 87Hz on every system startup The Open Source Drivers are Okay for regular Unity but many games don't work on it hence I had to install the nvidia drivers. I have been facing this since the Beta Phase although this is on a fresh installation of 12.04 final release. I am also providing my Xorg.conf file just in case it might help http://paste.ubuntu.com/952196/ Also for some reason Displays shows my CRT monitor as Laptop but on open source drivers it was mentioning it as a 14" CRT only This bug is also present on Edubuntu 12.04 This is not present on Xubuntu 12.04 I had selected to install updates and 3rd party software on the install and was greeted with a correct refresh rate screen on the Boot Up. I like Xubuntu.

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  • Entity Framework Batch Update and Future Queries

    - by pwelter34
    Entity Framework Extended Library A library the extends the functionality of Entity Framework. Features Batch Update and Delete Future Queries Audit Log Project Package and Source NuGet Package PM> Install-Package EntityFramework.Extended NuGet: http://nuget.org/List/Packages/EntityFramework.Extended Source: http://github.com/loresoft/EntityFramework.Extended Batch Update and Delete A current limitations of the Entity Framework is that in order to update or delete an entity you have to first retrieve it into memory. Now in most scenarios this is just fine. There are however some senerios where performance would suffer. Also, for single deletes, the object must be retrieved before it can be deleted requiring two calls to the database. Batch update and delete eliminates the need to retrieve and load an entity before modifying it. Deleting //delete all users where FirstName matches context.Users.Delete(u => u.FirstName == "firstname"); Update //update all tasks with status of 1 to status of 2 context.Tasks.Update( t => t.StatusId == 1, t => new Task {StatusId = 2}); //example of using an IQueryable as the filter for the update var users = context.Users .Where(u => u.FirstName == "firstname"); context.Users.Update( users, u => new User {FirstName = "newfirstname"}); Future Queries Build up a list of queries for the data that you need and the first time any of the results are accessed, all the data will retrieved in one round trip to the database server. Reducing the number of trips to the database is a great. Using this feature is as simple as appending .Future() to the end of your queries. To use the Future Queries, make sure to import the EntityFramework.Extensions namespace. Future queries are created with the following extension methods... Future() FutureFirstOrDefault() FutureCount() Sample // build up queries var q1 = db.Users .Where(t => t.EmailAddress == "[email protected]") .Future(); var q2 = db.Tasks .Where(t => t.Summary == "Test") .Future(); // this triggers the loading of all the future queries var users = q1.ToList(); In the example above, there are 2 queries built up, as soon as one of the queries is enumerated, it triggers the batch load of both queries. // base query var q = db.Tasks.Where(t => t.Priority == 2); // get total count var q1 = q.FutureCount(); // get page var q2 = q.Skip(pageIndex).Take(pageSize).Future(); // triggers execute as a batch int total = q1.Value; var tasks = q2.ToList(); In this example, we have a common senerio where you want to page a list of tasks. In order for the GUI to setup the paging control, you need a total count. With Future, we can batch together the queries to get all the data in one database call. Future queries work by creating the appropriate IFutureQuery object that keeps the IQuerable. The IFutureQuery object is then stored in IFutureContext.FutureQueries list. Then, when one of the IFutureQuery objects is enumerated, it calls back to IFutureContext.ExecuteFutureQueries() via the LoadAction delegate. ExecuteFutureQueries builds a batch query from all the stored IFutureQuery objects. Finally, all the IFutureQuery objects are updated with the results from the query. Audit Log The Audit Log feature will capture the changes to entities anytime they are submitted to the database. The Audit Log captures only the entities that are changed and only the properties on those entities that were changed. The before and after values are recorded. AuditLogger.LastAudit is where this information is held and there is a ToXml() method that makes it easy to turn the AuditLog into xml for easy storage. The AuditLog can be customized via attributes on the entities or via a Fluent Configuration API. Fluent Configuration // config audit when your application is starting up... var auditConfiguration = AuditConfiguration.Default; auditConfiguration.IncludeRelationships = true; auditConfiguration.LoadRelationships = true; auditConfiguration.DefaultAuditable = true; // customize the audit for Task entity auditConfiguration.IsAuditable<Task>() .NotAudited(t => t.TaskExtended) .FormatWith(t => t.Status, v => FormatStatus(v)); // set the display member when status is a foreign key auditConfiguration.IsAuditable<Status>() .DisplayMember(t => t.Name); Create an Audit Log var db = new TrackerContext(); var audit = db.BeginAudit(); // make some updates ... db.SaveChanges(); var log = audit.LastLog;

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  • Measuring Usability with Common Industry Format (CIF) Usability Tests

    - by Applications User Experience
    Sean Rice, Manager, Applications User Experience A User-centered Research and Design Process The Oracle Fusion Applications user experience was five years in the making. The development of this suite included an extensive and comprehensive user experience design process: ethnographic research, low-fidelity workflow prototyping, high fidelity user interface (UI) prototyping, iterative formative usability testing, development feedback and iteration, and sales and customer evaluation throughout the design cycle. However, this process does not stop when our products are released. We conduct summative usability testing using the ISO 25062 Common Industry Format (CIF) for usability test reports as an organizational framework. CIF tests allow us to measure the overall usability of our released products.  These studies provide benchmarks that allow for comparisons of a specific product release against previous versions of our product and against other products in the marketplace. What Is a CIF Usability Test? CIF refers to the internationally standardized method for reporting usability test findings used by the software industry. The CIF is based on a formal, lab-based test that is used to benchmark the usability of a product in terms of human performance and subjective data. The CIF was developed and is endorsed by more than 375 software customer and vendor organizations led by the National Institute for Standards and Technology (NIST), a US government entity. NIST sponsored the CIF through the American National Standards Institute (ANSI) and International Organization for Standardization (ISO) standards-making processes. Oracle played a key role in developing the CIF. The CIF report format and metrics are consistent with the ISO 9241-11 definition of usability: “The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use.” Our goal in conducting CIF tests is to measure performance and satisfaction of a representative sample of users on a set of core tasks and to help predict how usable a product will be with the larger population of customers. Why Do We Perform CIF Testing? The overarching purpose of the CIF for usability test reports is to promote incorporation of usability as part of the procurement decision-making process for interactive products. CIF provides a common format for vendors to report the methods and results of usability tests to customer organizations, and enables customers to compare the usability of our software to that of other suppliers. CIF also enables us to compare our current software with previous versions of our software. CIF Testing for Fusion Applications Oracle Fusion Applications comprises more than 100 modules in seven different product families. These modules encompass more than 400 task flows and 400 user roles. Due to resource constraints, we cannot perform comprehensive CIF testing across the entire product suite. Therefore, we had to develop meaningful inclusion criteria and work with other stakeholders across the applications development organization to prioritize product areas for testing. Ultimately, we want to test the product areas for which customers might be most interested in seeing CIF data. We also want to build credibility with customers; we need to be able to make the case to current and prospective customers that the product areas tested are representative of the product suite as a whole. Our goal is to test the top use cases for each product. The primary activity in the scoping process was to work with the individual product teams to identify the key products and business process task flows in each product to test. We prioritized these products and flows through a series of negotiations among the user experience managers, product strategy, and product management directors for each of the primary product families within the Oracle Fusion Applications suite (Human Capital Management, Supply Chain Management, Customer Relationship Management, Financials, Projects, and Procurement). The end result of the scoping exercise was a list of 47 proposed CIF tests for the Fusion Applications product suite.  Figure 1. A participant completes tasks during a usability test in Oracle’s Usability Labs Fusion Supplier Portal CIF Test The first Fusion CIF test was completed on the Supplier Portal application in July of 2011.  Fusion Supplier Portal is part of an integrated suite of Procurement applications that helps supplier companies manage orders, schedules, shipments, invoices, negotiations and payments. The user roles targeted for the usability study were Supplier Account Receivables Specialists and Supplier Sales Representatives, including both experienced and inexperienced users across a wide demographic range.  The test specifically focused on the following functionality and features: Manage payments – view payments Manage invoices – view invoice status and create invoices Manage account information – create new contact, review bank account information Manage agreements – find and view agreement, upload agreement lines, confirm status of agreement lines upload Manage purchase orders (PO) – view history of PO, request change to PO, find orders Manage negotiations – respond to request for a quote, check the status of a negotiation response These product areas were selected to represent the most important subset of features and functionality of the flow, in terms of frequency and criticality of use by customers. A total of 20 users participated in the usability study. The results of the Supplier Portal evaluation were favorable and exceeded our expectations. Figure 2. Fusion Supplier Portal Next Studies We plan to conduct two Fusion CIF usability studies per product family over the next nine months. The next product to be tested will be Self-service Procurement. End users are currently being recruited to participate in this usability study, and the test sessions are scheduled to begin during the last week of November.

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  • Data Mining Resources

    - by Dejan Sarka
    There are many different types of analyses, each one with its own pros and cons. Relational reports have a predefined structure, and end users cannot change it. They are simple to use for end users. Reports can use real-time data and snapshots of data to show the state of a report at specific points in time. One of the drawbacks is that report authoring is limited to IT pros and advanced users. Any kind of dynamic restructuring is very limited. If real-time data is used for a report, the report has a negative impact on the performance of the source system. Processing of the reports might be slow because the data comes from relational database management systems, which are not optimized for reporting only. If you create a semantic model of your data, your end users can create ad-hoc report structures. However, the development is more complex because a developer is needed to create these semantic models. For OLAP, you typically use specialized database management systems. You get lightning speed of analyses. End users can use rich and thin clients to interactively change the structure of the report. Typically, they do it graphically. However, the development of an OLAP system is many times quite complex. It involves the preparation and maintenance of an enterprise data warehouse and OLAP cubes. In order to exploit the possibility of real-time restructuring of reports, the users must be both active and educated. The data is usually stale, as it is loaded into data warehouses and OLAP cubes with a scheduled process. With data mining, a structure is not selected in advance; it searches for the structure. As a result, data mining can give you the most valuable results because you can discover patterns you did not expect. A data mining model structure is limited only by the attributes that you use to train the model. One of the drawbacks is that a lot of knowledge is needed for a successful data mining project. End users have to understand the results. Subject matter experts and IT professionals need to understand business problem thoroughly. The development might be sometimes even more complex than the development of OLAP cubes. Each type of analysis has its own place in an enterprise system. SQL Server has tools for all kinds of analyses. However, data mining is the most advanced way of analyzing the data; this is the “I” in BI. In order to get the most out of it, you need to learn quite a lot. In this blog post, I am gathering together resources for learning, including forthcoming events. Books Multiple authors: SQL Server MVP Deep Dives – I wrote an introductory data mining chapter there. Erik Veerman, Teo Lachev and Dejan Sarka: MCTS Self-Paced Training Kit (Exam 70-448): Microsoft SQL Server 2008 - Business Intelligence Development and Maintenance – you can find a good overview of a complete BI solution, including data mining, in this book. Jamie MacLennan, ZhaoHui Tang, and Bogdan Crivat: Data Mining with Microsoft SQL Server 2008 – can’t miss this book if you want to mine your data with SQL Server tools. Michael Berry, Gordon Linoff: Mastering Data Mining: The Art and Science of Customer Relationship Management – data mining from both, business and technical perspective. Dorian Pyle: Data Preparation for Data Mining – an in-depth book about data preparation. Thomas and Ronald Wonnacott: Introductory Statistics – if you thought that you could get away without statistics, then you are not serious about data mining. Jiawei Han and Micheline Kamber: Data Mining Concepts and Techniques – in-depth explanation of the most popular data mining algorithms. Michael Berry and Gordon Linoff: Data Mining Techniques – another book that explains data mining algorithms, more fro a business perspective. Paolo Guidici: Applied Data Mining – very mathematical book, only if you enjoy statistics and mathematics in general. Forthcoming presentations I am presenting two data mining related sessions during the PASS Summit in Charlotte, NC: Wednesday, October 16th, 2013 - Fraud Detection: Notes from the Field – I am showing how to use data mining for a specific business problem. The presentation is based on real-life projects. Friday, October 18th: Excel 2013 Advanced Analytics – I am focusing on Excel Data Mining Add-ins, and how to use them together with Power Pivot and other add-ins. This is the most you can get out of Excel. Sinergija 2013, Belgrade, Serbia Tuesday, October 22nd: Excel 2013 Analytics to the Max – another presentation focusing on the most advanced analytics you can get in Excel. SQL Rally Amsterdam, Netherlands Thursday, November 7th: Advanced Analytics in Excel 2013 – and again I am presenting about data mining in Excel. Why three different titles for the same presentation? I don’t know, I guess I forgot the name I proposed every time right after I sent the proposal. Courses Data Mining with SQL Server 2012 – I wrote a 3-day course for SolidQ. If you are interested in this course, which I could also deliver in a shorter seminar way, you can contact your closes SolidQ subsidiary, or, of course, me directly on addresses [email protected] or [email protected]. This course could also complement the existing courseware portfolio of training providers, which are welcome to contact me as well. OK, now you know: no more excuses, start learning data mining, get the most out of your data

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  • Project Management, Developer being project managers manager

    - by marabutt
    I am in the planning stages of a project and am looking to hire a project manager. I want be doing some coding and keeping an eye on all parts of the project but feel a project manager will get better results than I could. I can project manage the project and not code and hire another coder or code myself and hire a project manager. I am worried that the project manager will fell impeded by having the project owner as part of the development team. If I run the project, the team might fall apart causing the project to fail. To stick within budget, I have to be involved in one capacity or another. Does anyone have experience with this situation or suggestions?

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  • Find Nearest Object

    - by ultifinitus
    I have a fairly sizable game engine created, and I'm adding some needed features, such as this, how do I find the nearest object from a list of points? In this case, I could simply use the Pythagorean theorem to find the distance, and check the results. I know I can't simply add x and y, because that's the distance to the object, if you only took right angle turns. However I'm wondering if there's something else I could do? I also have a collision system, where essentially I turn objects into smaller objects on a smaller grid, kind of like a minimap, and only if objects exist in the same gridspace do I check for collisions, I could do the same thing, only make the gridspace larger to check for closeness. (rather than checking every. single. object) however that would take additional setup in my base class and clutter up the already cluttered object. TL;DR Question: Is there something efficient and accurate that I can use to detect which object is closest, based on a list of points and sizes?

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  • Congratulations to Gavin Payne–Microsoft Certified Architect

    - by Christian
    Huge congratulations to Gavin who became the 6th person in the WORLD outside Microsoft to qualify as a Microsoft Certified Architect in SQL Server today. Gavin’s worked so hard for this since the start of the year and all that work culminated in a grilling 4 hour review board during the PASS summit in Seattle less than 2 weeks ago -- he received his official results last night. To put things into perspective, there are only 25 people on the planet that are qualified to this level in SQL Server; only 6 of those don’t work for Microsoft; and 2 of those work for Coeo. Coeo is the only partner in the UK to have an MCA in SQL Server, and now we have 2! Well done Gavin, we’re all very proud of what you’ve achieved!   Christian Bolton - MCA, MCM, MVP Technical Director http://coeo.com - SQL Server Consulting & Managed Services You can read more about the Certified Architect program on Microsoft’s website here: http://bit.ly/4ar5QP

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  • 7 Web Design Tutorials from PSD to HTML/CSS

    - by Sushaantu
    Some time back when I was looking for some tutorials to create a website from scratch i.e. the process from designing the PSD to slice it and CSS/XHTML it, then not many quality results appeared. But that was like almost an year back and a lot of water has flown down the river Thanes since then. In this list I will give you links to some wonderful tutorials teaching you in a step by step way to design a website. These tutorials are ideal for someone who is learning web designing and has grasp of basic CSS, XHTML and little designing on Photoshop. How to Design and Code Web 2.0 Style Web Design Design a website from PSD to HTML Designing and Coding a Grunge Web Design from Scratch Creating a CSS layout from scratch Build a Sleek Portfolio Site from Scratch Designing and Coding a web design from scratch Design and Code a Dark and Sleek Web Design

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  • Convert a Door Peephole Viewer into a Fisheye Camera Lens

    - by Jason Fitzpatrick
    Commercial fish eye lenses are a niche product and carry a hefty price tag; if you’re looking to goof around with fish eye photography on the cheap, this $6 tutorial is for you. Courtesy of Dave from Knobtop–a thrifty DIY photography video blog–this hack uses dirt cheap parts (the whole build is composed of a PVC pipe reducer and a door peephole lens) to bring you fun fish eye photography on a budget. Check out the video above to see the build and the results, then hit up the link below to check out the notes on the video for more information. Fisheye Lens for $6 [via DIY Photography] HTG Explains: What Is Two-Factor Authentication and Should I Be Using It? HTG Explains: What Is Windows RT and What Does It Mean To Me? HTG Explains: How Windows 8′s Secure Boot Feature Works & What It Means for Linux

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  • ASP.NET Web API and Simple Value Parameters from POSTed data

    - by Rick Strahl
    In testing out various features of Web API I've found a few oddities in the way that the serialization is handled. These are probably not super common but they may throw you for a loop. Here's what I found. Simple Parameters from Xml or JSON Content Web API makes it very easy to create action methods that accept parameters that are automatically parsed from XML or JSON request bodies. For example, you can send a JavaScript JSON object to the server and Web API happily deserializes it for you. This works just fine:public string ReturnAlbumInfo(Album album) { return album.AlbumName + " (" + album.YearReleased.ToString() + ")"; } However, if you have methods that accept simple parameter types like strings, dates, number etc., those methods don't receive their parameters from XML or JSON body by default and you may end up with failures. Take the following two very simple methods:public string ReturnString(string message) { return message; } public HttpResponseMessage ReturnDateTime(DateTime time) { return Request.CreateResponse<DateTime>(HttpStatusCode.OK, time); } The first one accepts a string and if called with a JSON string from the client like this:var client = new HttpClient(); var result = client.PostAsJsonAsync<string>(http://rasxps/AspNetWebApi/albums/rpc/ReturnString, "Hello World").Result; which results in a trace like this: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnString HTTP/1.1Content-Type: application/json; charset=utf-8Host: rasxpsContent-Length: 13Expect: 100-continueConnection: Keep-Alive "Hello World" produces… wait for it: null. Sending a date in the same fashion:var client = new HttpClient(); var result = client.PostAsJsonAsync<DateTime>(http://rasxps/AspNetWebApi/albums/rpc/ReturnDateTime, new DateTime(2012, 1, 1)).Result; results in this trace: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnDateTime HTTP/1.1Content-Type: application/json; charset=utf-8Host: rasxpsContent-Length: 30Expect: 100-continueConnection: Keep-Alive "\/Date(1325412000000-1000)\/" (yes still the ugly MS AJAX date, yuk! This will supposedly change by RTM with Json.net used for client serialization) produces an error response: The parameters dictionary contains a null entry for parameter 'time' of non-nullable type 'System.DateTime' for method 'System.Net.Http.HttpResponseMessage ReturnDateTime(System.DateTime)' in 'AspNetWebApi.Controllers.AlbumApiController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter. Basically any simple parameters are not parsed properly resulting in null being sent to the method. For the string the call doesn't fail, but for the non-nullable date it produces an error because the method can't handle a null value. This behavior is a bit unexpected to say the least, but there's a simple solution to make this work using an explicit [FromBody] attribute:public string ReturnString([FromBody] string message) andpublic HttpResponseMessage ReturnDateTime([FromBody] DateTime time) which explicitly instructs Web API to read the value from the body. UrlEncoded Form Variable Parsing Another similar issue I ran into is with POST Form Variable binding. Web API can retrieve parameters from the QueryString and Route Values but it doesn't explicitly map parameters from POST values either. Taking our same ReturnString function from earlier and posting a message POST variable like this:var formVars = new Dictionary<string,string>(); formVars.Add("message", "Some Value"); var content = new FormUrlEncodedContent(formVars); var client = new HttpClient(); var result = client.PostAsync(http://rasxps/AspNetWebApi/albums/rpc/ReturnString, content).Result; which produces this trace: POST http://rasxps/AspNetWebApi/albums/rpc/ReturnString HTTP/1.1Content-Type: application/x-www-form-urlencodedHost: rasxpsContent-Length: 18Expect: 100-continue message=Some+Value When calling ReturnString:public string ReturnString(string message) { return message; } unfortunately it does not map the message value to the message parameter. This sort of mapping unfortunately is not available in Web API. Web API does support binding to form variables but only as part of model binding, which binds object properties to the POST variables. Sending the same message as in the previous example you can use the following code to pick up POST variable data:public string ReturnMessageModel(MessageModel model) { return model.Message; } public class MessageModel { public string Message { get; set; }} Note that the model is bound and the message form variable is mapped to the Message property as would other variables to properties if there were more. This works but it's not very dynamic. There's no real easy way to retrieve form variables (or query string values for that matter) in Web API's Request object as far as I can discern. Well only if you consider this easy:public string ReturnString() { var formData = Request.Content.ReadAsAsync<FormDataCollection>().Result; return formData.Get("message"); } Oddly FormDataCollection does not allow for indexers to work so you have to use the .Get() method which is rather odd. If you're running under IIS/Cassini you can always resort to the old and trusty HttpContext access for request data:public string ReturnString() { return HttpContext.Current.Request.Form["message"]; } which works fine and is easier. It's kind of a bummer that HttpRequestMessage doesn't expose some sort of raw Request object that has access to dynamic data - given that it's meant to serve as a generic REST/HTTP API that seems like a crucial missing piece. I don't see any way to read query string values either. To me personally HttpContext works, since I don't see myself using self-hosted code much.© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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