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• How do I prove or disprove "god" objects are wrong?

  - by honestduane

  Problem Summary: Long story short, I inherited a code base and an development team I am not allowed to replace and the use of God Objects is a big issue. Going forward, I want to have us re-factor things but I am getting push-back from the teams who want to do everything with God Objects "because its easier" and this means I would not be allowed to re-factor. I pushed back citing my years of dev experience, that I'm the new boss who was hired to know these things, etc, and so did the third party offshore companies account sales rep, and this is now at the executive level and my meeting is tomorrow and I want to go in with a lot of technical ammo to advocate best practices because I feel it will be cheaper in the long run (And I personally feel that is what the third party is worried about) for the company. My issue is from a technical level, I know its good long term but I'm having trouble with the ultra short term and 6 months term, and while its something I "know" I cant prove it with references and cited resources outside of one person (Robert C. Martin, aka Uncle Bob), as that is what I am being asked to do as I have been told having data from one person and only one person (Robert C Martin) is not good enough of an argument. Question: What are some resources I can cite directly (Title, year published, page number, quote) by well known experts in the field that explicitly say this use of "God" Objects/Classes/Systems is bad (or good, since we are looking for the most technically valid solution)? Research I have already done: I have a number of books here and I have searched their indexes for the use of the words "god object" and "god class". I found that oddly its almost never used and the copy of the GoF book I have for example, never uses it (At least according to the index in front of me) but I have found it in 2 books per the below, but I want more I can use. I checked the Wikipedia page for "God Object" and its currently a stub with little reference links so although I personally agree with that it says, It doesn't have much I can use in an environment where personal experience is not considered valid. The book cited is also considered too old to be valid by the people I am debating these technical points with as the argument they are making is that "it was once thought to be bad but nobody could prove it, and now modern software says "god" objects are good to use". I personally believe that this statement is incorrect, but I want to prove the truth, whatever it is. In Robert C Martin's "Agile Principles, Patterns, and Practices in C#" (ISBN: 0-13-185725-8, hardcover) where on page 266 it states "Everybody knows that god classes are a bad idea. We don't want to concentrate all the intelligence of a system into a single object or a single function. One of the goals of OOD is the partitioning and distribution of behavior into many classes and many function." -- And then goes on to say sometimes its better to use God Classes anyway sometimes (Citing micro-controllers as an example). In Robert C Martin's "Clean Code: A Handbook of Agile Software Craftsmanship" page 136 (And only this page) talks about the "God class" and calls it out as a prime example of a violation of the "classes should be small" rule he uses to promote the Single Responsibility Principle" starting on on page 138. The problem I have is all my references and citations come from the same person (Robert C. Martin), and am from the same single person/source. I am being told that because he is just one guy, my desire to not use "God Classes" is invalid and not accepted as a standard best practice in the software industry. Is this true? Am I doing things wrong from a technical perspective by trying to keep to the teaching of Uncle Bob? God Objects and Object Oriented Programming and Design: The more I think of this the more I think this is more something you learn when you study OOP and its never explicitly called out; Its implicit to good design is my thinking (Feel free to correct me, please, as I want to learn), The problem is I "know" this, but but not everybody does, so in this case its not considered a valid argument because I am effectively calling it out as universal truth when in fact most people are statistically ignorant of it since statistically most people are not programmers. Conclusion: I am at a loss on what to search for to get the best additional results to cite, since they are making a technical claim and I want to know the truth and be able to prove it with citations like a real engineer/scientist, even if I am biased against god objects due to my personal experience with code that used them. Any assistance or citations would be deeply appreciated.

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• GlassFish Clustering with DCOM on Windows

  - by ByronNevins

  DCOM - Distributed COM, a Microsoft protocol for communicating with Windows machines. Why use DCOM? In GlassFish 3.1 SSH is used as the standard way to run commands on remote nodes for clustering.  It is very difficult for users to get SSH configured properly on Windows.  SSH does not come with Windows so we have to depend on third party tools.  And then the user is forced to install and configure these tools -- which can be tricky. DCOM is available on all supported platforms.  It is built-in to Windows. The idea is to use DCOM to communicate with remote Windows nodes.  This has the huge advantage that the user has to do minimal, if any, configuration on the Windows nodes. Implementation HighlightsTwo open Source Libraries have been added to GlassFish: Jcifs – a SAMBA implementation in Java J-interop – A Java implementation for making DCOM calls to remote Windows computers.   Note that any supported platform can use DCOM to work with Windows nodes -- not just Windows.E.g. you can have a Linux DAS work with Windows remote instances.All existing SSH commands now have a corresponding DCOM command – except for setup-ssh which isn’t needed for DCOM.  validate-dcom is an all new command. New DCOM Commands create-node-dcom delete-node-dcom install-node-dcom list-nodes-dcom ping-node-dcom uninstall-node-dcom update-node-dcom validate-dcom setup-local-dcom (This is only available via Update Center for GlassFish 3.1.2) These commands are in-place in the trunk (4.0).  And in the branch (3.1.2) Windows Configuration Challenges There are an infinite number of possible configurations of Windows if you look at it as a combination of main release, service-pack, special drivers, software, configuration etc.  Later versions of Windows err on the side of tightening security be default.  This means that the Windows host may need to have configuration changes made.These configuration changes mostly need to be made by the user.  setup-local-dcom will assist you in making required changes to the Windows Registry.  See the reference blogs for details. The validate-dcom Command validate-dcom is a crucial command.  It should be run before any other commands.  If it does not run successfully then there is no point in running other commands.The validate-dcom command must be used from a DAS machine to test a different Windows machine.  If  validate-dcom runs successfully you can be confident that all the DCOM commands will work.  Conversely, the opposite is also true:  If validate-dcom fails, then no DCOM commands will work. What validate-dcom does Verify that the remote host is not the local machine. Resolves the remote host name Checks that the remote DCOM port is being listened on (135, 139) Checks that the remote host’s File Sharing is enabled (port 445) It copies a file (a script) to the remote host to verify that SAMBA is working and authorization is correct It runs a script that it copied on-the-fly to the remote host. Tips and Tricks The bread and butter commands that use DCOM are existing commands like create-instance, start-instance etc.   All of the commands that have dcom in their name are for dealing with the actual nodes. The way the software works is to call asadmin.bat on the remote machine and run a command.  This means that you can track these commands easily on the remote machine with the usual tools.  E.g. using AS_LOGFILE, looking at log files, etc.  It’s easy to attach a debugger to the remote asadmin process, “just in time”, if necessary. How to debug the remote commands:Edit the asadmin.bat file that is in the glassfish/bin folder.  Use glassfish/lib/nadmin.bat in GlassFish 4.0+Add these options to the java call:-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=1234  Now if you run, say start-instance on DAS, you can attach your debugger, at your leisure, to the remote machines port 1234.  It will be running start-local-instance and patiently waiting for you to attach.

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• Auto DOP and Concurrency

  - by jean-pierre.dijcks

  After spending some time in the cloud, I figured it is time to come down to earth and start discussing some of the new Auto DOP features some more. As Database Machines (the v2 machine runs Oracle Database 11.2) are effectively selling like hotcakes, it makes some sense to talk about the new parallel features in more detail. For basic understanding make sure you have read the initial post. The focus there is on Auto DOP and queuing, which is to some extend the focus here. But now I want to discuss the concurrency a little and explain some of the relevant parameters and their impact, specifically in a situation with concurrency on the system. The goal of Auto DOP The idea behind calculating the Automatic Degree of Parallelism is to find the highest possible DOP (ideal DOP) that still scales. In other words, if we were to increase the DOP even more  above a certain DOP we would see a tailing off of the performance curve and the resource cost / performance would become less optimal. Therefore the ideal DOP is the best resource/performance point for that statement. The goal of Queuing On a normal production system we should see statements running concurrently. On a Database Machine we typically see high concurrency rates, so we need to find a way to deal with both high DOP’s and high concurrency. Queuing is intended to make sure we Don’t throttle down a DOP because other statements are running on the system Stay within the physical limits of a system’s processing power Instead of making statements go at a lower DOP we queue them to make sure they will get all the resources they want to run efficiently without trashing the system. The theory – and hopefully – practice is that by giving a statement the optimal DOP the sum of all statements runs faster with queuing than without queuing. Increasing the Number of Potential Parallel Statements To determine how many statements we will consider running in parallel a single parameter should be looked at. That parameter is called PARALLEL_MIN_TIME_THRESHOLD. The default value is set to 10 seconds. So far there is nothing new here…, but do realize that anything serial (e.g. that stays under the threshold) goes straight into processing as is not considered in the rest of this post. Now, if you have a system where you have two groups of queries, serial short running and potentially parallel long running ones, you may want to worry only about the long running ones with this parallel statement threshold. As an example, lets assume the short running stuff runs on average between 1 and 15 seconds in serial (and the business is quite happy with that). The long running stuff is in the realm of 1 – 5 minutes. It might be a good choice to set the threshold to somewhere north of 30 seconds. That way the short running queries all run serial as they do today (if it ain’t broken, don’t fix it) and allows the long running ones to be evaluated for (higher degrees of) parallelism. This makes sense because the longer running ones are (at least in theory) more interesting to unleash a parallel processing model on and the benefits of running these in parallel are much more significant (again, that is mostly the case). Setting a Maximum DOP for a Statement Now that you know how to control how many of your statements are considered to run in parallel, lets talk about the specific degree of any given statement that will be evaluated. As the initial post describes this is controlled by PARALLEL_DEGREE_LIMIT. This parameter controls the degree on the entire cluster and by default it is CPU (meaning it equals Default DOP). For the sake of an example, let’s say our Default DOP is 32. Looking at our 5 minute queries from the previous paragraph, the limit to 32 means that none of the statements that are evaluated for Auto DOP ever runs at more than DOP of 32. Concurrently Running a High DOP A basic assumption about running high DOP statements at high concurrency is that you at some point in time (and this is true on any parallel processing platform!) will run into a resource limitation. And yes, you can then buy more hardware (e.g. expand the Database Machine in Oracle’s case), but that is not the point of this post… The goal is to find a balance between the highest possible DOP for each statement and the number of statements running concurrently, but with an emphasis on running each statement at that highest efficiency DOP. The PARALLEL_SERVER_TARGET parameter is the all important concurrency slider here. Setting this parameter to a higher number means more statements get to run at their maximum parallel degree before queuing kicks in.  PARALLEL_SERVER_TARGET is set per instance (so needs to be set to the same value on all 8 nodes in a full rack Database Machine). Just as a side note, this parameter is set in processes, not in DOP, which equates to 4* Default DOP (2 processes for a DOP, default value is 2 * Default DOP, hence a default of 4 * Default DOP). Let’s say we have PARALLEL_SERVER_TARGET set to 128. With our limit set to 32 (the default) we are able to run 4 statements concurrently at the highest DOP possible on this system before we start queuing. If these 4 statements are running, any next statement will be queued. To run a system at high concurrency the PARALLEL_SERVER_TARGET should be raised from its default to be much closer (start with 60% or so) to PARALLEL_MAX_SERVERS. By using both PARALLEL_SERVER_TARGET and PARALLEL_DEGREE_LIMIT you can control easily how many statements run concurrently at good DOPs without excessive queuing. Because each workload is a little different, it makes sense to plan ahead and look at these parameters and set these based on your requirements.

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• SQL SERVER – SSMS: Database Consistency History Report

  - by Pinal Dave

  Doctor and Database The last place I like to visit is always a hospital. With the monsoon season starting, intermittent rains, it has become sort of a routine to get a cycle of fever every other year (seriously I hate it). So when I visit my doctor, it is always interesting in the way he quizzes me. The routine question of – “How many days have you had this?”, “Is there any pattern?”, “Did you drench in rain?”, “Do you have any other symptom?” and so on. The idea here is that the doctor wants to find any anomaly or a pattern that will guide him to a viral or bacterial type. Most of the time they get it based on experience and sometimes after a battery of tests. So if there is consistent behavior to your problem, there is always a solution out. SQL Server has its way to find if the server data / files are in consistent state using the DBCC commands. Back to SQL Server In real life, Database consistency check is one of the critical operations a DBA generally doesn’t give much priority. Many readers of my blogs have asked many times, how do we know if the database is consistent? How do I read output of DBCC CHECKDB and find if everything is right or not? My common answer to all of them is – look at the bottom of checkdb (or checktable) output and look for below line. CHECKDB found 0 allocation errors and 0 consistency errors in database ‘DatabaseName’. Above is a “good sign” because we are seeing zero allocation and zero consistency error. If you are seeing non-zero errors then there is some problem with the database. Sample output is shown as below: CHECKDB found 0 allocation errors and 2 consistency errors in database ‘DatabaseName’. repair_allow_data_loss is the minimum repair level for the errors found by DBCC CHECKDB (DatabaseName). If we see non-zero error then most of the time (not always) we get repair options depending on the level of corruption. There is risk involved with above option (repair_allow_data_loss), that is – we would lose the data. Sometimes the option would be repair_rebuild which is little safer. Though these options are available, it is important to find the root cause to the problem. In standard report, there is a report which can show the history of checkdb executed for the selected database. Since this is a database level report, we need to right click on database, click Reports, click Standard Reports and then choose “Database Consistency History” report. The information in this report is picked from default trace. If default trace is disabled or there is no checkdb run or information is not there in default trace (because it’s rolled over), we would get report like below. As we can see report says it very clearly: Currently, no execution history of CHECKDB is available or default trace is not enabled. To demonstrate, I have caused corruption in one of the database and did below steps. Run CheckDB so that errors are reported. Fix the corruption by losing the data using repair option Run CheckDB again to check if corruption is cleared. After that I have launched the report and below is what we would see. If you are lazy like me and don’t want to run the report manually for each database then below query would be handy to provide same report for all database. This query is runs behind the scenes by the report. All I have done is remove the filter for database name (at the last – highlighted). DECLARE @curr_tracefilename VARCHAR(500); DECLARE @base_tracefilename VARCHAR(500); DECLARE @indx INT; SELECT @curr_tracefilename = path FROM sys.traces WHERE is_default = 1; SET @curr_tracefilename = REVERSE(@curr_tracefilename); SELECT @indx  = PATINDEX('%\%', @curr_tracefilename) ; SET @curr_tracefilename = REVERSE(@curr_tracefilename); SET @base_tracefilename = LEFT( @curr_tracefilename,LEN(@curr_tracefilename) - @indx) + '\log.trc'; SELECT  SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),36, PATINDEX('%executed%',TEXTData)-36) AS command ,       LoginName ,       StartTime ,       CONVERT(INT,SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),PATINDEX('%found%',TEXTData) +6,PATINDEX('%errors %',TEXTData)-PATINDEX('%found%',TEXTData)-6)) AS errors ,       CONVERT(INT,SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),PATINDEX('%repaired%',TEXTData) +9,PATINDEX('%errors.%',TEXTData)-PATINDEX('%repaired%',TEXTData)-9)) repaired ,       SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),PATINDEX('%time:%',TEXTData)+6,PATINDEX('%hours%',TEXTData)-PATINDEX('%time:%',TEXTData)-6)+':'+SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),PATINDEX('%hours%',TEXTData) +6,PATINDEX('%minutes%',TEXTData)-PATINDEX('%hours%',TEXTData)-6)+':'+SUBSTRING(CONVERT(NVARCHAR(MAX),TEXTData),PATINDEX('%minutes%',TEXTData) +8,PATINDEX('%seconds.%',TEXTData)-PATINDEX('%minutes%',TEXTData)-8) AS time FROM::fn_trace_gettable( @base_tracefilename, DEFAULT) WHERE EventClass = 22 AND SUBSTRING(TEXTData,36,12) = 'DBCC CHECKDB' -- AND DatabaseName = @DatabaseName; Don’t get worried about the logic above. All it is doing is reading the trace files, parsing below entry and getting out information for underlined words. DBCC CHECKDB (CorruptedDatabase) executed by sa found 2 errors and repaired 0 errors. Elapsed time: 0 hours 0 minutes 0 seconds.  Internal database snapshot has split point LSN = 00000029:00000030:0001 and first LSN = 00000029:00000020:0001. Hopefully now onwards you would run checkdb and understand the importance of it. As responsible DBAs I am sure you are already doing it, let me know how often do you actually run them on you production environment? Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Reports

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• Who broke the build?

  - by Martin Hinshelwood

  I recently sent round a list of broken builds at SSW and asked for them to be fixed or deleted if they are not being used. My colleague Peter came back with a couple of questions which I love as it tells me that at least one person reads my email I think first we need to answer a couple of other questions related to builds in general.   Why do we want the build to pass? Any developer can pick up a project and build it Standards can be enforced Constant quality is maintained Problems in code are identified early What could a failed build signify? Developers have not built and tested their code properly before checking in. Something added depends on a local resource that is not under version control or does not exist on the target computer. Developers are not writing tests to cover common problems. There are not enough tests to cover problems. Now we know why, lets answer Peters questions: Where is this list? (can we see it somehow) You can normally only see the builds listed for each project. But, you have a little application called “Build Notifications” on your computer. It is installed when you install Visual Studio 2010. Figure: Staring the build notification application on Windows 7. Once you have it open (it may disappear into your system tray) you should click “Options” and select all the projects you are involved in. This application only lists projects that have builds, so don’t worry if it is not listed. This just means you are about to setup a build, right? I just selected ALL projects that have builds. Figure: All builds are listed here In addition to seeing the list you will also get toast notification of build failure’s. How can we get more info on what broke the build? (who is interesting too, to point the finger but more important is what) The only thing worse than breaking the build, is continuing to develop on a broken build! Figure: I have highlighted the users who either are bad for braking the build, or very bad for not fixing it. To find out what is wrong with a build you need to open the build definition. You can open a web version by double clicking the build in the image above, or you can open it from “Team Explorer”. Just connect to your project and open out the “Builds” tree. Then Open the build by double clicking on it. Figure: Opening a build is easy, but double click it and then open a build run from the list. Figure: Good example, the build and tests have passed Figure: Bad example, there are 133 errors preventing POK from being built on the build server. For identifying failures see: Solution: Getting Silverlight to build on Team Build 2010 RC Solution: Testing Web Services with MSTest on Team Build Finding the problem on a partially succeeded build So, Peter asked about blame, let’s have a look and see: Figure: The build has been broken for so long I have no idea when it was broken, but everyone on this list is to blame (I am there too) The rest of the history is lost in the sands of time, there is no way to tell when the build was originally broken, or by whom, or even if it ever worked in the first place. Build should be protected by the team that uses them and the only way to do that is to have them own them. It is fine for me to go in and setup a build, but the ownership for a build should always reside with the person who broke it last. Conclusion This is an example of a pointless build. Lets be honest, if you have a system like TFS in place and builds are constantly left broken, or not added to projects then your developers don’t yet understand the value. I have found that adding a Gated Check-in helps instil that understanding of value. If you prevent them from checking in without passing that basic quality gate of “your code builds on another computer” then it makes them look more closely at why they can’t check-in. I have had builds fail because one developer had a “d” drive, but the build server did not. That is what they are there to catch.   If you want to know what builds to create and why I wrote a post on “Do you know the minimum builds to create on any branch?”   Technorati Tags: TFS2010,Gated Check-in,Builds,Build Failure,Broken Build

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• User is trying to leave! Set at-least confirm alert on browser(tab) close event!!

  - by kaushalparik27

  This is something that might be annoying or irritating for end user. Obviously, It's impossible to prevent end user from closing the/any browser. Just think of this if it becomes possible!!!. That will be a horrible web world where everytime you will be attacked by sites and they will not allow to close your browser until you confirm your shopping cart and do the payment. LOL:) You need to open the task manager and might have to kill the running browser exe processes.Anyways; Jokes apart, but I have one situation where I need to alert/confirm from the user in any anyway when they try to close the browser or change the url. Think of this: You are creating a single page intranet asp.net application where your employee can enter/select their TDS/Investment Declarations and you wish to at-least ALERT/CONFIRM them if they are attempting to:[1] Close the Browser[2] Close the Browser Tab[3] Attempt to go some other site by Changing the urlwithout completing/freezing their declaration.So, Finally requirement is clear. I need to alert/confirm the user what he is going to do on above bulleted events. I am going to use window.onbeforeunload event to set the javascript confirm alert box to appear.    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }    </script>See! you are halfway done!. So, every time browser unloads the page, above confirm alert causes to appear on front of user like below:By saying here "every time browser unloads the page"; I mean to say that whenever page loads or postback happens the browser onbeforeunload event will be executed. So, event a button submit or a link submit which causes page to postback would tend to execute the browser onbeforeunload event to fire!So, now the hurdle is how can we prevent the alert "Not to show when page is being postback" via any button/link submit? Answer is JQuery :)Idea is, you just need to set the script reference src to jQuery library and Set the window.onbeforeunload event to null when any input/link causes a page to postback.Below will be the complete code:<head runat="server">    <title></title>    <script src="jquery.min.js" type="text/javascript"></script>    <script language="JavaScript" type="text/javascript">        window.onbeforeunload = confirmExit;        function confirmExit() {            return "You are about to exit the system before freezing your declaration! If you leave now and never return to freeze your declaration; then they will not go into effect and you may lose tax deduction, Are you sure you want to leave now?";        }        $(function() {            $("a").click(function() {                window.onbeforeunload = null;            });            $("input").click(function() {                window.onbeforeunload = null;            });        });    </script></head><body>    <form id="form1" runat="server">    <div></div>    </form></body></html>So, By this post I have tried to set the confirm alert if user try to close the browser/tab or try leave the site by changing the url. I have attached a working example with this post here. I hope someone might find it helpful.

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• Allowing Access to HttpContext in WCF REST Services

  - by Rick Strahl

  If you’re building WCF REST Services you may find that WCF’s OperationContext, which provides some amount of access to Http headers on inbound and outbound messages, is pretty limited in that it doesn’t provide access to everything and sometimes in a not so convenient manner. For example accessing query string parameters explicitly is pretty painful: [OperationContract] [WebGet] public string HelloWorld() { var properties = OperationContext.Current.IncomingMessageProperties; var property = properties[HttpRequestMessageProperty.Name] as HttpRequestMessageProperty; string queryString = property.QueryString; var name = StringUtils.GetUrlEncodedKey(queryString,"Name"); return "Hello World " + name; } And that doesn’t account for the logic in GetUrlEncodedKey to retrieve the querystring value. It’s a heck of a lot easier to just do this: [OperationContract] [WebGet] public string HelloWorld() { var name = HttpContext.Current.Request.QueryString["Name"] ?? string.Empty; return "Hello World " + name; } Ok, so if you follow the REST guidelines for WCF REST you shouldn’t have to rely on reading query string parameters manually but instead rely on routing logic, but you know what: WCF REST is a PITA anyway and anything to make things a little easier is welcome. To enable the second scenario there are a couple of steps that you have to take on your service implementation and the configuration file. Add aspNetCompatibiltyEnabled in web.config Fist you need to configure the hosting environment to support ASP.NET when running WCF Service requests. This ensures that the ASP.NET pipeline is fired up and configured for every incoming request. <system.serviceModel>     <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" /> </system.serviceModel> Markup your Service Implementation with AspNetCompatibilityRequirements Attribute Next you have to mark up the Service Implementation – not the contract if you’re using a separate interface!!! – with the AspNetCompatibilityRequirements attribute: [ServiceContract(Namespace = "RateTestService")] [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)] public class RestRateTestProxyService Typically you’ll want to use Allowed as the preferred option. The other options are NotAllowed and Required. Allowed will let the service run if the web.config attribute is not set. Required has to have it set. All these settings determine whether an ASP.NET host AppDomain is used for requests. Once Allowed or Required has been set on the implemented class you can make use of the ASP.NET HttpContext object. When I allow for ASP.NET compatibility in my WCF services I typically add a property that exposes the Context and Request objects a little more conveniently: public HttpContext Context { get { return HttpContext.Current; } } public HttpRequest Request { get { return HttpContext.Current.Request; } } While you can also access the Response object and write raw data to it and manipulate headers THAT is probably not such a good idea as both your code and WCF will end up writing into the output stream. However it might be useful in some situations where you need to take over output generation completely and return something completely custom. Remember though that WCF REST DOES actually support that as well with Stream responses that essentially allow you to return any kind of data to the client so using Response should really never be necessary. Should you or shouldn’t you? WCF purists will tell you never to muck with the platform specific features or the underlying protocol, and if you can avoid it you definitely should avoid it. Querystring management in particular can be handled largely with Url Routing, but there are exceptions of course. Try to use what WCF natively provides – if possible as it makes the code more portable. For example, if you do enable ASP.NET Compatibility you won’t be able to self host a WCF REST service. At the same time realize that especially in WCF REST there are number of big holes or access to some features are a royal pain and so it’s not unreasonable to access the HttpContext directly especially if it’s only for read-only access. Since everything in REST works of URLS and the HTTP protocol more control and easier access to HTTP features is a key requirement to building flexible services. It looks like vNext of the WCF REST stuff will feature many improvements along these lines with much deeper native HTTP support that is often so useful in REST applications along with much more extensibility that allows for customization of the inputs and outputs as data goes through the request pipeline. I’m looking forward to this stuff as WCF REST as it exists today still is a royal pain (in fact I’m struggling with a mysterious version conflict/crashing error on my machine that I have not been able to resolve – grrrr…).© Rick Strahl, West Wind Technologies, 2005-2011Posted in ASP.NET  AJAX  WCF  

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• Backpacks and Booth Paint: TechEd 2012

  - by The Un-T Guy

  Arriving in the parking lot of the Orange County Convention Center, I immediately knew I was in the right place. As far as the eye could see, the acres of asphalt were awash in backpacks, quirky (to be kind) outfits, and bad haircuts. This was the place. This was Microsoft Mecca v2012 for geeks and nerds, the Central Florida event of the year, a gathering of high tech professionals whose skills I both greatly respect and, frankly, fear a little. I was wholly and completely out of element, a dork in a vast sea of geek jumbo. It like was wearing dockers and a golf shirt walking into a RenFaire, but one with really crappy costumes and no turkey legs...save those attached to some of the attendees. Of course the corporate whores...errrr, vendors were in place, ready to parlay the convention's fre-nerd-ic energy into millions of dollars by convincing the big-brained and under-sexed in the crowd (i.e., virtually all of them...present company excluded, of course) that their product or service was the only thing standing between them and professional success, industry fame, and clear skin. "With KramTech 2012," they seemed to scream, "you will be THE ROCK STAR of your company's IT department!" As car shows and tattoo parlors learned long ago, Tech companies seem to believe that the best way to attract the attention of this crowd is through the hint of the promise of sex. They recruit and deploy an army of "sales reps" whose primary qualifications appear to be long hair, short skirts, high heels, and a vagina. Unlike their distant cousins in the car and body art industries, however, this sub-species of booth paint (semi-gloss decoration that adds nothing to the substance of the product) seems torn between committing to being all-out sex objects and recognition that they are in the presence of intelligent, discerning people. People who are smart enough to know exactly what these vendors are doing. Also unlike their distant car show and tattoo shop cousins, these young women (what…are there no gay tech professionals who could use some eye candy?) seem to realize that while IT remains a male-dominated field, there are ever-increasing numbers of intelligent, capable, strong professional women – women who’ve battled to make it in this field through hard work and work performance rather than a hard body and performing after work. This is not to say that all of the young female sales reps are there only because of their physical attributes. Many are competent, intelligent, and driven -- not to mention attractive. They're working hard on the front lines of delivering the next generation of technology. The distinction is pretty clear, however, between these young professionals and the booth paint. The former enthusiastically deliver credible information about the products they’re hawking. The latter are positioned in the aisles, uncomfortably avoiding eye contact as they struggle to operate the badge readers. Surprisingly, not all of the women in attendance seemed to object to the objectification of their younger sisters. One IT professional woman who came of age in the industry (mostly in IT marketing) said, “I have no problem with it. I was a ‘booth babe’ for years and it doesn’t bother me at all.” Others, however, weren’t quite so gracious. One woman I spoke with, an IT manager from Cheyenne, Wyoming, said it was demeaning and frankly, as more and more women grow into IT management positions, not a great marketing idea. “Using these young women is, to me, no different than vendors giving out t-shirts to attract attention. It’s sad because it’s still hard for a woman to be respected in the IT field and this just perpetuates the outdated notion that IT is a male-dominated field.” She went on to say that decisions by vendors to employ these young women in this “inappropriate way” could impact her purchasing decisions. “I might be swayed toward a vendor who has women on staff who are intelligent and dynamic rather than the vendors who use the ‘decoration’ girls.” So in many ways, the IT industry is no different than most other industries as it struggles to maximize performance by finding and developing talent – all of the talent, not just the 50% with a penis. Women in IT, like their brethren, struggle to find their niche in the field, to grow professionally, and reach for the brass ring, struggling to overcome obstacles as they climb the mountain of professional success in a never-ending cycle of economic uncertainty. But as (generally) well-educated and highly-trained professionals, they are probably better positioned than those in many other industries. Beside, they’ve got one other advantage over their non-IT counterparts as they attempt their ascent to the summit: They’ve already got the backpacks.

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• Joins in single-table queries

  - by Rob Farley

  Tables are only metadata. They don’t store data. I’ve written something about this before, but I want to take a viewpoint of this idea around the topic of joins, especially since it’s the topic for T-SQL Tuesday this month. Hosted this time by Sebastian Meine (@sqlity), who has a whole series on joins this month. Good for him – it’s a great topic. In that last post I discussed the fact that we write queries against tables, but that the engine turns it into a plan against indexes. My point wasn’t simply that a table is actually just a Clustered Index (or heap, which I consider just a special type of index), but that data access always happens against indexes – never tables – and we should be thinking about the indexes (specifically the non-clustered ones) when we write our queries. I described the scenario of looking up phone numbers, and how it never really occurs to us that there is a master list of phone numbers, because we think in terms of the useful non-clustered indexes that the phone companies provide us, but anyway – that’s not the point of this post. So a table is metadata. It stores information about the names of columns and their data types. Nullability, default values, constraints, triggers – these are all things that define the table, but the data isn’t stored in the table. The data that a table describes is stored in a heap or clustered index, but it goes further than this. All the useful data is going to live in non-clustered indexes. Remember this. It’s important. Stop thinking about tables, and start thinking about indexes. So let’s think about tables as indexes. This applies even in a world created by someone else, who doesn’t have the best indexes in mind for you. I’m sure you don’t need me to explain Covering Index bit – the fact that if you don’t have sufficient columns “included” in your index, your query plan will either have to do a Lookup, or else it’ll give up using your index and use one that does have everything it needs (even if that means scanning it). If you haven’t seen that before, drop me a line and I’ll run through it with you. Or go and read a post I did a long while ago about the maths involved in that decision. So – what I’m going to tell you is that a Lookup is a join. When I run SELECT CustomerID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 285; against the AdventureWorks2012 get the following plan: I’m sure you can see the join. Don’t look in the query, it’s not there. But you should be able to see the join in the plan. It’s an Inner Join, implemented by a Nested Loop. It’s pulling data in from the Index Seek, and joining that to the results of a Key Lookup. It clearly is – the QO wouldn’t call it that if it wasn’t really one. It behaves exactly like any other Nested Loop (Inner Join) operator, pulling rows from one side and putting a request in from the other. You wouldn’t have a problem accepting it as a join if the query were slightly different, such as SELECT sod.OrderQty FROM Sales.SalesOrderHeader AS soh JOIN Sales.SalesOrderDetail as sod on sod.SalesOrderID = soh.SalesOrderID WHERE soh.SalesPersonID = 285; Amazingly similar, of course. This one is an explicit join, the first example was just as much a join, even thought you didn’t actually ask for one. You need to consider this when you’re thinking about your queries. But it gets more interesting. Consider this query: SELECT SalesOrderID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 276 AND CustomerID = 29522; It doesn’t look like there’s a join here either, but look at the plan. That’s not some Lookup in action – that’s a proper Merge Join. The Query Optimizer has worked out that it can get the data it needs by looking in two separate indexes and then doing a Merge Join on the data that it gets. Both indexes used are ordered by the column that’s indexed (one on SalesPersonID, one on CustomerID), and then by the CIX key SalesOrderID. Just like when you seek in the phone book to Farley, the Farleys you have are ordered by FirstName, these seek operations return the data ordered by the next field. This order is SalesOrderID, even though you didn’t explicitly put that column in the index definition. The result is two datasets that are ordered by SalesOrderID, making them very mergeable. Another example is the simple query SELECT CustomerID FROM Sales.SalesOrderHeader WHERE SalesPersonID = 276; This one prefers a Hash Match to a standard lookup even! This isn’t just ordinary index intersection, this is something else again! Just like before, we could imagine it better with two whole tables, but we shouldn’t try to distinguish between joining two tables and joining two indexes. The Query Optimizer can see (using basic maths) that it’s worth doing these particular operations using these two less-than-ideal indexes (because of course, the best indexese would be on both columns – a composite such as (SalesPersonID, CustomerID – and it would have the SalesOrderID column as part of it as the CIX key still). You need to think like this too. Not in terms of excusing single-column indexes like the ones in AdventureWorks2012, but in terms of having a picture about how you’d like your queries to run. If you start to think about what data you need, where it’s coming from, and how it’s going to be used, then you will almost certainly write better queries. …and yes, this would include when you’re dealing with regular joins across multiples, not just against joins within single table queries.

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• SQL SERVER – What is Incremental Statistics? – Performance improvements in SQL Server 2014 – Part 1

  - by Pinal Dave

  This is the first part of the series Incremental Statistics. Here is the index of the complete series. What is Incremental Statistics? – Performance improvements in SQL Server 2014 – Part 1 Simple Example of Incremental Statistics – Performance improvements in SQL Server 2014 – Part 2 DMV to Identify Incremental Statistics – Performance improvements in SQL Server 2014 – Part 3 Statistics are considered one of the most important aspects of SQL Server Performance Tuning. You might have often heard the phrase, with related to performance tuning. “Update Statistics before you take any other steps to tune performance”. Honestly, I have said above statement many times and many times, I have personally updated statistics before I start to do any performance tuning exercise. You may agree or disagree to the point, but there is no denial that Statistics play an extremely vital role in the performance tuning. SQL Server 2014 has a new feature called Incremental Statistics. I have been playing with this feature for quite a while and I find that very interesting. After spending some time with this feature, I decided to write about this subject over here. New in SQL Server 2014 – Incremental Statistics Well, it seems like lots of people wants to start using SQL Server 2014′s new feature of Incremetnal Statistics. However, let us understand what actually this feature does and how it can help. I will try to simplify this feature first before I start working on the demo code. Code for all versions of SQL Server Here is the code which you can execute on all versions of SQL Server and it will update the statistics of your table. The keyword which you should pay attention is WITH FULLSCAN. It will scan the entire table and build brand new statistics for you which your SQL Server Performance Tuning engine can use for better estimation of your execution plan. UPDATE STATISTICS TableName(StatisticsName) WITH FULLSCAN Who should learn about this? Why? If you are using partitions in your database, you should consider about implementing this feature. Otherwise, this feature is pretty much not applicable to you. Well, if you are using single partition and your table data is in a single place, you still have to update your statistics the same way you have been doing. If you are using multiple partitions, this may be a very useful feature for you. In most cases, users have multiple partitions because they have lots of data in their table. Each partition will have data which belongs to itself. Now it is very common that each partition are populated separately in SQL Server. Real World Example For example, if your table contains data which is related to sales, you will have plenty of entries in your table. It will be a good idea to divide the partition into multiple filegroups for example, you can divide this table into 3 semesters or 4 quarters or even 12 months. Let us assume that we have divided our table into 12 different partitions. Now for the month of January, our first partition will be populated and for the month of February our second partition will be populated. Now assume, that you have plenty of the data in your first and second partition. Now the month of March has just started and your third partition has started to populate. Due to some reason, if you want to update your statistics, what will you do? In SQL Server 2012 and earlier version You will just use the code of WITH FULLSCAN and update the entire table. That means even though you have only data in third partition you will still update the entire table. This will be VERY resource intensive process as you will be updating the statistics of the partition 1 and 2 where data has not changed at all. In SQL Server 2014 You will just update the partition of Partition 3. There is a special syntax where you can now specify which partition you want to update now. The impact of this is that it is smartly merging the new data with old statistics and update the entire statistics without doing FULLSCAN of your entire table. This has a huge impact on performance. Remember that the new feature in SQL Server 2014 does not change anything besides the capability to update a single partition. However, there is one feature which is indeed attractive. Previously, when table data were changed 20% at that time, statistics update were triggered. However, now the same threshold is applicable to a single partition. That means if your partition faces 20% data, change it will also trigger partition level statistics update which, when merged to your final statistics will give you better performance. In summary If you are not using a partition, this feature is not applicable to you. If you are using a partition, this feature can be very helpful to you. Tomorrow: We will see working code of SQL Server 2014 Incremental Statistics. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: SQL Statistics, Statistics

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• Get your content off Blogger.com

  - by Daniel Moth

  Due to blogger.com deprecating FTP users I've decided to move my blog. When I think of the content of a blog, 4 items come to mind: blog posts, comments, binary files that the blog posts linked to (e.g. images, ZIP files) and the CSS+structure of the blog. 1. Binaries The binary files you used in your blog posts are sitting on your own web space, so really blogger.com is not involved with that. Nothing for you to do at this stage, I'll come back to these in another post. 2. CSS and structure In the best case this exists as a separate CSS file on your web space (so no action for now) or in a worst case, like me, your CSS is embedded with the HTML. In the latter case, simply navigate from you dashboard to "Template" then "Edit HTML" and copy paste the contents of the box. Save that locally in a txt file and we'll come back to that in another post. 3. Blog posts and Comments The blog posts and comments exist in all the HTML files on your own web space. Parsing HTML files to extract that can be painful, so it is easier to download the XML files from blogger's servers that contain all your blog posts and comments. 3.1 Single XML file, but incomplete The obvious thing to do is go into your dashboard "Settings" and under the "Basic" tab look at the top next to "Blog Tools". There is a link there to "Export blog" which downloads an XML file with both comments and posts. The problem with that is that it only contains 200 comments - if you have more than that, you will lose the surplus. Also, this XML file has a lot of noise, compared to the better solution described next. (note that a tool I will refer to in a future post deals with either kind of XML file) 3.2 Multiple XML files First you need to find your blog ID. In case you don't know what that is, navigate to the "Template" as described in section 2 above. You will find references to the blog id in the HTML there, but you can also see it as part of the URL in your browser: blogger.com/template-edit.g?blogID=YOUR_NUMERIC_ID. Mine is 7 digits. You can now navigate to these URLs to download the XML for your posts and comments respectively: blogger.com/feeds/YOUR_NUMERIC_ID/posts/default?max-results=500&start-index=1 blogger.com/feeds/YOUR_NUMERIC_ID/comments/default?max-results=200&start-index=1 Note that you can only get 500 posts at a time and only 200 comments at a time. To get more than that you have to change the URL and download the next batch. To get you started, to get the XML for the next 500 posts and next 200 comments respectively you’d have to use these URLs: blogger.com/feeds/YOUR_NUMERIC_ID/posts/default?max-results=500&start-index=501 blogger.com/feeds/YOUR_NUMERIC_ID/comments/default?max-results=200&start-index=201 ...and so on and so forth. Keep all the XML files in the same folder on your local machine (with nothing else in there). 4. Validating the XML aka editing older blog posts The XML files you just downloaded really contain HTML fragments inside for all your blog posts. If you are like me, your blog posts did not conform to XHTML so passing them to an XML parser (which is what we will want to do) will result in the XML parser choking. So the next step is to fix that. This can be no work at all for you, or a huge time sink or just a couple hours of pain (which was my case). The process I followed was to attempt to load the XML files using XmlDocument.Load and wait for the exception to be thrown from my code. The exception would point to the exact offending line and column which would help me fix the issue. Rather than fix it in the XML itself, I would go back and edit the offending blog post and fix it there - recommended! Then I'd repeat the cycle until the XML could be loaded in the XmlDocument. To give you an idea, some of the issues I encountered are: extra or missing quotes in img and href elements, direct usage of chevrons instead of encoding them as &lt;, missing closing tags, mismatched nested pairs of elements and capitalization of html elements. For a full list of things that may go wrong see this. 5. Opportunity for other changes I also found a few posts that did not have a category assigned so I fixed those too. I took the further opportunity to create new categories and tag some of my blog posts with that. Note that I did not remove/change categories of existing posts, but only added.   In an another post we'll see how to use the XML files you stored in the local folder… Comments about this post welcome at the original blog.

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• How to Use Steam In-Home Streaming

  - by Chris Hoffman

  Steam’s In-Home Streaming is now available to everyone, allowing you to stream PC games from one PC to another PC on the same local network. Use your gaming PC to power your laptops and home theater system. This feature doesn’t allow you to stream games over the Internet, only the same local network. Even if you tricked Steam, you probably wouldn’t get good streaming performance over the Internet. Why Stream? When you use Steam In-Home streaming, one PC sends its video and audio to another PC. The other PC views the video and audio like it’s watching a movie, sending back mouse, keyboard, and controller input to the other PC. This allows you to have a fast gaming PC power your gaming experience on slower PCs. For example, you could play graphically demanding games on a laptop in another room of your house, even if that laptop has slower integrated graphics. You could connect a slower PC to your television and use your gaming PC without hauling it into a different room in your house. Streaming also enables cross-platform compatibility. You could have a Windows gaming PC and stream games to a Mac or Linux system. This will be Valve’s official solution for compatibility with old Windows-only games on the Linux (Steam OS) Steam Machines arriving later this year. NVIDIA offers their own game streaming solution, but it requires certain NVIDIA graphics hardware and can only stream to an NVIDIA Shield device. How to Get Started In-Home Streaming is simple to use and doesn’t require any complex configuration — or any configuration, really. First, log into the Steam program on a Windows PC. This should ideally be a powerful gaming PC with a powerful CPU and fast graphics hardware. Install the games you want to stream if you haven’t already — you’ll be streaming from your PC, not from Valve’s servers. (Valve will eventually allow you to stream games from Mac OS X, Linux, and Steam OS systems, but that feature isn’t yet available. You can still stream games to these other operating systems.) Next, log into Steam on another computer on the same network with the same Steam username. Both computers have to be on the same subnet of the same local network. You’ll see the games installed on your other PC in the Steam client’s library. Click the Stream button to start streaming a game from your other PC. The game will launch on your host PC, and it will send its audio and video to the PC in front of you. Your input on the client will be sent back to the server. Be sure to update Steam on both computers if you don’t see this feature. Use the Steam > Check for Updates option within Steam and install the latest update. Updating to the latest graphics drivers for your computer’s hardware is always a good idea, too. Improving Performance Here’s what Valve recommends for good streaming performance: Host PC: A quad-core CPU for the computer running the game, minimum. The computer needs enough processor power to run the game, compress the video and audio, and send it over the network with low latency. Streaming Client: A GPU that supports hardware-accelerated H.264 decoding on the client PC. This hardware is included on all recent laptops and PCs. Ifyou have an older PC or netbook, it may not be able to decode the video stream quickly enough. Network Hardware: A wired network connection is ideal. You may have success with wireless N or AC networks with good signals, but this isn’t guaranteed. Game Settings: While streaming a game, visit the game’s setting screen and lower the resolution or turn off VSync to speed things up. In-Home Steaming Settings: On the host PC, click Steam > Settings and select In-Home Streaming to view the In-Home Streaming settings. You can modify your streaming settings to improve performance and reduce latency. Feel free to experiment with the options here and see how they affect performance — they should be self-explanatory. Check Valve’s In-Home Streaming documentation for troubleshooting information. You can also try streaming non-Steam games. Click Games > Add a Non-Steam Game to My Library on your host PC and add a PC game you have installed elsewhere on your system. You can then try streaming it from your client PC. Valve says this “may work but is not officially supported.” Image Credit: Robert Couse-Baker on Flickr, Milestoned on Flickr

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• ct.sym steals the ASM class

  - by Geertjan

  Some mild consternation on the Twittersphere yesterday. Marcus Lagergren not being able to find the ASM classes in JDK 8 in NetBeans IDE: And there's no such problem in Eclipse (and apparently in IntelliJ IDEA). Help, does NetBeans (despite being incredibly awesome) suck, after all? The truth of the matter is that there's something called "ct.sym" in the JDK. When javac is compiling code, it doesn't link against rt.jar. Instead, it uses a special symbol file lib/ct.sym with class stubs. Internal JDK classes are not put in that symbol file, since those are internal classes. You shouldn't want to use them, at all. However, what if you're Marcus Lagergren who DOES need these classes? I.e., he's working on the internal JDK classes and hence needs to have access to them. Fair enough that the general Java population can't access those classes, since they're internal implementation classes that could be changed anytime and one wouldn't want all unknown clients of those classes to start breaking once changes are made to the implementation, i.e., this is the rt.jar's internal class protection mechanism. But, again, we're now Marcus Lagergen and not the general Java population. For the solution, read Jan Lahoda, NetBeans Java Editor guru, here: https://netbeans.org/bugzilla/show_bug.cgi?id=186120 In particular, take note of this: AFAIK, the ct.sym is new in JDK6. It contains stubs for all classes that existed in JDK5 (for compatibility with existing programs that would use private JDK classes), but does not contain implementation classes that were introduced in JDK6 (only API classes). This is to prevent application developers to accidentally use JDK's private classes (as such applications would be unportable and may not run on future versions of JDK). Note that this is not really a NB thing - this is the behavior of javac from the JDK. I do not know about any way to disable this except deleting ct.sym or the option mentioned above. Regarding loading the classes: JVM uses two classpath's: classpath and bootclasspath. rt.jar is on the bootclasspath and has precedence over anything on the "custom" classpath, which is used by the application. The usual way to override classes on bootclasspath is to start the JVM with "-Xbootclasspath/p:" option, which prepends the given jars (and presumably also directories) to bootclasspath. Hence, let's take the first option, the simpler one, and simply delete the "ct.sym" file. Again, only because we need to work with those internal classes as developers of the JDK, not because we want to hack our way around "ct.sym", which would mean you'd not have portable code at the end of the day. Go to the JDK 8 lib folder and you'll find the file: Delete it. Start NetBeans IDE again, either on JDK 7 or JDK 8, doesn't make a difference for these purposes, create a new Java application (or use an existing one), make sure you have set the JDK above as the JDK of the application, and hey presto: The above obviously assumes you have a build of JDK 8 that actually includes the ASM package. And below you can see that not only are the classes found but my build succeeded, even though I'm using internal JDK classes. The yellow markings in the sidebar mean that the classes are imported but not used in the code, where normally, if I hadn't removed "ct.sym", I would have seen red error marking instead, and the code wouldn't have compiled. Note: I've tried setting "-XDignore.symbol.file" in "netbeans.conf" and in other places, but so far haven't got that to work. Simply deleting the "ct.sym" file (or back it up somewhere and put it back when needed) is quite clearly the most straightforward solution. Ultimately, if you want to be able to use those internal classes while still having portable code, do you know what you need to do? You need to create a JDK bug report stating that you need an internal class to be added to "ct.sym". Probably you'll get a motivation back stating WHY that internal class isn't supposed to be used externally. There must be a reason why those classes aren't available for external usage, otherwise they would have been added to "ct.sym". So, now the only remaining question is why the Eclipse compiler doesn't hide the internal JDK classes. Apparently the Eclipse compiler ignores the "ct.sym" file. In other words, at the end of the day, far from being a bug in NetBeans... we have now found a (pretty enormous, I reckon) bug in Eclipse. The Eclipse compiler does not protect you from using internal JDK classes and the code that you create in Eclipse may not work with future releases of the JDK, since the JDK team is simply going to be changing those classes that are not found in the "ct.sym" file while assuming (correctly, thanks to the presence of "ct.sym" mechanism) that no code in the world, other than JDK code, is tied to those classes.

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• Big Data – Various Learning Resources – How to Start with Big Data? – Day 20 of 21

  - by Pinal Dave

  In yesterday’s blog post we learned how to become a Data Scientist for Big Data. In this article we will go over various learning resources related to Big Data. In this series we have covered many of the most essential details about Big Data. At the beginning of this series, I have encouraged readers to send me questions. One of the most popular questions is - “I want to learn more about Big Data. Where can I learn it?” This is indeed a great question as there are plenty of resources out to learn about Big Data and it is indeed difficult to select on one resource to learn Big Data. Hence I decided to write here a few of the very important resources which are related to Big Data. Learn from Pluralsight Pluralsight is a global leader in high-quality online training for hardcore developers.  It has fantastic Big Data Courses and I started to learn about Big Data with the help of Pluralsight. Here are few of the courses which are directly related to Big Data. Big Data: The Big Picture Big Data Analytics with Tableau NoSQL: The Big Picture Understanding NoSQL Data Analysis Fundamentals with Tableau I encourage all of you start with this video course as they are fantastic fundamentals to learn Big Data. Learn from Apache Resources at Apache are single point the most authentic learning resources. If you want to learn fundamentals and go deep about every aspect of the Big Data, I believe you must understand various concepts in Apache’s library. I am pretty impressed with the documentation and I am personally referencing it every single day when I work with Big Data. I strongly encourage all of you to bookmark following all the links for authentic big data learning. Haddop - The Apache Hadoop® project develops open-source software for reliable, scalable, distributed computing. Ambari: A web-based tool for provisioning, managing, and monitoring Apache Hadoop clusters which include support for Hadoop HDFS, Hadoop MapReduce, Hive, HCatalog, HBase, ZooKeeper, Oozie, Pig and Sqoop. Ambari also provides a dashboard for viewing cluster health such as heat maps and ability to view MapReduce, Pig and Hive applications visually along with features to diagnose their performance characteristics in a user-friendly manner. Avro: A data serialization system. Cassandra: A scalable multi-master database with no single points of failure. Chukwa: A data collection system for managing large distributed systems. HBase: A scalable, distributed database that supports structured data storage for large tables. Hive: A data warehouse infrastructure that provides data summarization and ad hoc querying. Mahout: A Scalable machine learning and data mining library. Pig: A high-level data-flow language and execution framework for parallel computation. ZooKeeper: A high-performance coordination service for distributed applications. Learn from Vendors One of the biggest issues with about learning Big Data is setting up the environment. Every Big Data vendor has different environment request and there are lots of things require to set up Big Data framework. Many of the users do not start with Big Data as they are afraid about the resources required to set up framework as well as a time commitment. Here Hortonworks have created fantastic learning environment. They have created Sandbox with everything one person needs to learn Big Data and also have provided excellent tutoring along with it. Sandbox comes with a dozen hands-on tutorial that will guide you through the basics of Hadoop as well it contains the Hortonworks Data Platform. I think Hortonworks did a fantastic job building this Sandbox and Tutorial. Though there are plenty of different Big Data Vendors I have decided to list only Hortonworks due to their unique setup. Please leave a comment if there are any other such platform to learn Big Data. I will include them over here as well. Learn from Books There are indeed few good books out there which one can refer to learn Big Data. Here are few good books which I have read. I will update the list as I will learn more. Ethics of Big Data Balancing Risk and Innovation Big Data for Dummies Head First Data Analysis: A Learner’s Guide to Big Numbers, Statistics, and Good Decisions If you search on Amazon there are millions of the books but I think above three books are a great set of books and it will give you great ideas about Big Data. Once you go through above books, you will have a clear idea about what is the next step you should follow in this series. You will be capable enough to make the right decision for yourself. Tomorrow In tomorrow’s blog post we will wrap up this series of Big Data. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• NoSQL Java API for MySQL Cluster: Questions & Answers

  - by Mat Keep

  The MySQL Cluster engineering team recently ran a live webinar, available now on-demand demonstrating the ClusterJ and ClusterJPA NoSQL APIs for MySQL Cluster, and how these can be used in building real-time, high scale Java-based services that require continuous availability. Attendees asked a number of great questions during the webinar, and I thought it would be useful to share those here, so others are also able to learn more about the Java NoSQL APIs. First, a little bit about why we developed these APIs and why they are interesting to Java developers. ClusterJ and Cluster JPA ClusterJ is a Java interface to MySQL Cluster that provides either a static or dynamic domain object model, similar to the data model used by JDO, JPA, and Hibernate. A simple API gives users extremely high performance for common operations: insert, delete, update, and query. ClusterJPA works with ClusterJ to extend functionality, including - Persistent classes - Relationships - Joins in queries - Lazy loading - Table and index creation from object model By eliminating data transformations via SQL, users get lower data access latency and higher throughput. In addition, Java developers have a more natural programming method to directly manage their data, with a complete, feature-rich solution for Object/Relational Mapping. As a result, the development of Java applications is simplified with faster development cycles resulting in accelerated time to market for new services. MySQL Cluster offers multiple NoSQL APIs alongside Java: - Memcached for a persistent, high performance, write-scalable Key/Value store, - HTTP/REST via an Apache module - C++ via the NDB API for the lowest absolute latency. Developers can use SQL as well as NoSQL APIs for access to the same data set via multiple query patterns – from simple Primary Key lookups or inserts to complex cross-shard JOINs using Adaptive Query Localization Marrying NoSQL and SQL access to an ACID-compliant database offers developers a number of benefits. MySQL Cluster’s distributed, shared-nothing architecture with auto-sharding and real time performance makes it a great fit for workloads requiring high volume OLTP. Users also get the added flexibility of being able to run real-time analytics across the same OLTP data set for real-time business insight. OK – hopefully you now have a better idea of why ClusterJ and JPA are available. Now, for the Q&A. Q & A Q. Why would I use Connector/J vs. ClusterJ? A. Partly it's a question of whether you prefer to work with SQL (Connector/J) or objects (ClusterJ). Performance of ClusterJ will be better as there is no need to pass through the MySQL Server. A ClusterJ operation can only act on a single table (e.g. no joins) - ClusterJPA extends that capability Q. Can I mix different APIs (ie ClusterJ, Connector/J) in our application for different query types? A. Yes. You can mix and match all of the API types, SQL, JDBC, ODBC, ClusterJ, Memcached, REST, C++. They all access the exact same data in the data nodes. Update through one API and new data is instantly visible to all of the others. Q. How many TCP connections would a SessionFactory instance create for a cluster of 8 data nodes? A. SessionFactory has a connection to the mgmd (management node) but otherwise is just a vehicle to create Sessions. Without using connection pooling, a SessionFactory will have one connection open with each data node. Using optional connection pooling allows multiple connections from the SessionFactory to increase throughput. Q. Can you give details of how Cluster J optimizes sharding to enhance performance of distributed query processing? A. Each data node in a cluster runs a Transaction Coordinator (TC), which begins and ends the transaction, but also serves as a resource to operate on the result rows. While an API node (such as a ClusterJ process) can send queries to any TC/data node, there are performance gains if the TC is where most of the result data is stored. ClusterJ computes the shard (partition) key to choose the data node where the row resides as the TC. Q. What happens if we perform two primary key lookups within the same transaction? Are they sent to the data node in one transaction? A. ClusterJ will send identical PK lookups to the same data node. Q. How is distributed query processing handled by MySQL Cluster ? A. If the data is split between data nodes then all of the information will be transparently combined and passed back to the application. The session will connect to a data node - typically by hashing the primary key - which then interacts with its neighboring nodes to collect the data needed to fulfil the query. Q. Can I use Foreign Keys with MySQL Cluster A. Support for Foreign Keys is included in the MySQL Cluster 7.3 Early Access release Summary The NoSQL Java APIs are packaged with MySQL Cluster, available for download here so feel free to take them for a spin today! Key Resources MySQL Cluster on-line demo  MySQL ClusterJ and JPA On-demand webinar  MySQL ClusterJ and JPA documentation MySQL ClusterJ and JPA whitepaper and tutorial

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• How to write a generic service in WCF

  - by rezaxp

  In one of my recent projects I needed a generic service as a facade to handle General activities such as CRUD.Therefor I searched as Many as I could but there was no Idea on generic services so I tried to figure it out by my self.Finally,I found a way :Create a generic contract as below :[ServiceContract] public interface IEntityReadService<TEntity>         where TEntity : EntityBase, new()     {         [OperationContract(Name = "Get")]         TEntity Get(Int64 Id);         [OperationContract(Name = "GetAll")]         List<TEntity> GetAll();         [OperationContract(Name = "GetAllPaged")]         List<TEntity> GetAll(int pageSize, int currentPageIndex, ref int totalRecords);         List<TEntity> GetAll(string whereClause, string orderBy, int pageSize, int currentPageIndex, ref int totalRecords);            }then create your service class :  public class GenericService<TEntity> :IEntityReadService<TEntity> where TEntity : EntityBase, new() {#region Implementation of IEntityReadService<TEntity>         public TEntity Get(long Id)         {             return BusinessController.Get(Id);         }         public List<TEntity> GetAll()         {             try             {                 return BusinessController.GetAll().ToList();             }             catch (Exception ex)             {                                  throw;             }                      }         public List<TEntity> GetAll(int pageSize, int currentPageIndex, ref int totalRecords)         {             return                 BusinessController.GetAll(pageSize, currentPageIndex, ref totalRecords).ToList();         }         public List<TEntity> GetAll(string whereClause, string orderBy, int pageSize, int currentPageIndex, ref int totalRecords)         {             return                 BusinessController.GetAll(pageSize, currentPageIndex, ref totalRecords, whereClause, orderBy).ToList();         }         #endregion} Then, set your EndPoint configuration in this way :<endpoint address="myAddress" binding="basicHttpBinding" bindingConfiguration="myBindingConfiguration1" contract="Contracts.IEntityReadService`1[[Entities.mySampleEntity, Entities]], Service.Contracts" />

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• SQL SERVER – Columnstore Index and sys.dm_db_index_usage_stats

  - by pinaldave

  As you know I have been writing on Columnstore Index for quite a while. Recently my friend Vinod Kumar wrote about  SQL Server 2012: ColumnStore Characteristics. A fantastic read on the subject if you have yet not caught up on that subject. After the blog post I called him and asked what should I write next on this subject. He suggested that I should write on DMV script which I have prepared related to Columnstore when I was writing our SQL Server Questions and Answers book. When we were writing this book SQL Server 2012 CTP versions were available. I had written few scripts related to SQL Server columnstore Index. I like Vinod’s idea and I decided to write about DMV, which we did not cover in the book as SQL Server 2012 was not released yet. We did not want to talk about the product which was not yet released. The first script which I had written was with DMV - sys.column_store_index_stats. This DMV was displaying the statistics of the columnstore indexes. When I attempted to run it on SQL Server 2012 RTM it gave me error suggesting that this DMV does not exists. Here is the script which I ran: SELECT * FROM sys.column_store_index_stats; It generated following error: Msg 208, Level 16, State 1, Line 1 Invalid object name ‘column_store_index_stats’. I was pretty confident that this DMV was available when I had written the scripts. The next reaction was to type ‘sys.’ only in SSMS and wait for intelisense to popup DMV list. I scrolled down and noticed that above said DMV did not exists there as well. Now this is not bug or missing feature. This was indeed something can happen because the version which I was practicing was early CTP version. If you go to the page of the DMV here, it clearly stats notice on the top of the page. This documentation is for preview only, and is subject to change in later releases. Now this was not alarming but my next thought was if this DMV is not there where can I find the information which this DMV was providing. Well, while I was thinking about this, I noticed that my another friend Balmukund Lakhani was online on personal messenger. Well, Balmukund is “Know All” kid. I have yet to find situation where I have not got my answers from him. I immediately pinged him and asked the question regarding where can I find information of ‘column_store_index_stats’. His answer was very abrupt but enlightening for sure. Here is our conversation: Pinal: Where can I find information of column_store_index_stats? Balmukund: Assume you have never worked with CTP before and now try to find the information which you are trying to find. Honestly  it was fantastic response from him. I was confused as I have played extensively with CTP versions of SQL Server 2012. Now his response give me big hint. I should have not looked for DMV but rather should have focused on what I wanted to do. I wanted to retrieve the statistics related to the index. In SQL Server 2008/R2, I was able to retrieve the statistics of the index from the DMV - sys.dm_db_index_usage_stats. I used the same DMV on SQL Server 2012 and it did retrieved the necessary information for me. Here is the updated script which gave me all the necessary information I was looking for. Matter of the fact, if I have used my earlier SQL Server 2008 R2 script this would have just worked fine. SELECT DB_NAME(Database_ID) DBName, SCHEMA_NAME(schema_id) AS SchemaName, OBJECT_NAME(ius.OBJECT_ID) ObjName, i.type_desc, i.name, user_seeks, user_scans, user_lookups, user_updates,* FROM sys.dm_db_index_usage_stats ius INNER JOIN sys.indexes i ON i.index_id = ius.index_id AND ius.OBJECT_ID = i.OBJECT_ID INNER JOIN sys.tables t ON t.OBJECT_ID = i.OBJECT_ID GO Let us see the resultset of above query. You will notice that column Type_desc describes the type of the index. You can additionally write WHERE condition on the column and only retrieve only selected type of Index. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• problem with loading in .FBX meshes in DirectX 10

  - by N0xus

  I'm trying to load in meshes into DirectX 10. I've created a bunch of classes that handle it and allow me to call in a mesh with only a single line of code in my main game class. How ever, when I run the program this is what renders: In the debug output window the following errors keep appearing: D3D10: ERROR: ID3D10Device::DrawIndexed: Input Assembler - Vertex Shader linkage error: Signatures between stages are incompatible. The reason is that Semantic 'TEXCOORD' is defined for mismatched hardware registers between the output stage and input stage. [ EXECUTION ERROR #343: DEVICE_SHADER_LINKAGE_REGISTERINDEX ] D3D10: ERROR: ID3D10Device::DrawIndexed: Input Assembler - Vertex Shader linkage error: Signatures between stages are incompatible. The reason is that the input stage requires Semantic/Index (POSITION,0) as input, but it is not provided by the output stage. [ EXECUTION ERROR #342: DEVICE_SHADER_LINKAGE_SEMANTICNAME_NOT_FOUND ] The thing is, I've no idea how to fix this. The code I'm using does work and I've simply brought all of that code into a new project of mine. There are no build errors and this only appears when the game is running The .fx file is as follows: float4x4 matWorld; float4x4 matView; float4x4 matProjection; struct VS_INPUT { float4 Pos:POSITION; float2 TexCoord:TEXCOORD; }; struct PS_INPUT { float4 Pos:SV_POSITION; float2 TexCoord:TEXCOORD; }; Texture2D diffuseTexture; SamplerState diffuseSampler { Filter = MIN_MAG_MIP_POINT; AddressU = WRAP; AddressV = WRAP; }; // // Vertex Shader // PS_INPUT VS( VS_INPUT input ) { PS_INPUT output=(PS_INPUT)0; float4x4 viewProjection=mul(matView,matProjection); float4x4 worldViewProjection=mul(matWorld,viewProjection); output.Pos=mul(input.Pos,worldViewProjection); output.TexCoord=input.TexCoord; return output; } // // Pixel Shader // float4 PS(PS_INPUT input ) : SV_Target { return diffuseTexture.Sample(diffuseSampler,input.TexCoord); //return float4(1.0f,1.0f,1.0f,1.0f); } RasterizerState NoCulling { FILLMODE=SOLID; CULLMODE=NONE; }; technique10 Render { pass P0 { SetVertexShader( CompileShader( vs_4_0, VS() ) ); SetGeometryShader( NULL ); SetPixelShader( CompileShader( ps_4_0, PS() ) ); SetRasterizerState(NoCulling); } } In my game, the .fx file and model are called and set as follows: Loading in shader file //Set the shader flags - BMD DWORD dwShaderFlags = D3D10_SHADER_ENABLE_STRICTNESS; #if defined( DEBUG ) || defined( _DEBUG ) dwShaderFlags |= D3D10_SHADER_DEBUG; #endif ID3D10Blob * pErrorBuffer=NULL; if( FAILED( D3DX10CreateEffectFromFile( TEXT("TransformedTexture.fx" ), NULL, NULL, "fx_4_0", dwShaderFlags, 0, md3dDevice, NULL, NULL, &m_pEffect, &pErrorBuffer, NULL ) ) ) { char * pErrorStr = ( char* )pErrorBuffer->GetBufferPointer(); //If the creation of the Effect fails then a message box will be shown MessageBoxA( NULL, pErrorStr, "Error", MB_OK ); return false; } //Get the technique called Render from the effect, we need this for rendering later on m_pTechnique=m_pEffect->GetTechniqueByName("Render"); //Number of elements in the layout UINT numElements = TexturedLitVertex::layoutSize; //Get the Pass description, we need this to bind the vertex to the pipeline D3D10_PASS_DESC PassDesc; m_pTechnique->GetPassByIndex( 0 )->GetDesc( &PassDesc ); //Create Input layout to describe the incoming buffer to the input assembler if (FAILED(md3dDevice->CreateInputLayout( TexturedLitVertex::layout, numElements,PassDesc.pIAInputSignature, PassDesc.IAInputSignatureSize, &m_pVertexLayout ) ) ) { return false; } model loading: m_pTestRenderable=new CRenderable(); //m_pTestRenderable->create<TexturedVertex>(md3dDevice,8,6,vertices,indices); m_pModelLoader = new CModelLoader(); m_pTestRenderable = m_pModelLoader->loadModelFromFile( md3dDevice,"armoredrecon.fbx" ); m_pGameObjectTest = new CGameObject(); m_pGameObjectTest->setRenderable( m_pTestRenderable ); // Set primitive topology, how are we going to interpet the vertices in the vertex buffer md3dDevice->IASetPrimitiveTopology( D3D10_PRIMITIVE_TOPOLOGY_TRIANGLELIST ); if ( FAILED( D3DX10CreateShaderResourceViewFromFile( md3dDevice, TEXT( "armoredrecon_diff.png" ), NULL, NULL, &m_pTextureShaderResource, NULL ) ) ) { MessageBox( NULL, TEXT( "Can't load Texture" ), TEXT( "Error" ), MB_OK ); return false; } m_pDiffuseTextureVariable = m_pEffect->GetVariableByName( "diffuseTexture" )->AsShaderResource(); m_pDiffuseTextureVariable->SetResource( m_pTextureShaderResource ); Finally, the draw function code: //All drawing will occur between the clear and present m_pViewMatrixVariable->SetMatrix( ( float* )m_matView ); m_pWorldMatrixVariable->SetMatrix( ( float* )m_pGameObjectTest->getWorld() ); //Get the stride(size) of the a vertex, we need this to tell the pipeline the size of one vertex UINT stride = m_pTestRenderable->getStride(); //The offset from start of the buffer to where our vertices are located UINT offset = m_pTestRenderable->getOffset(); ID3D10Buffer * pVB=m_pTestRenderable->getVB(); //Bind the vertex buffer to input assembler stage - md3dDevice->IASetVertexBuffers( 0, 1, &pVB, &stride, &offset ); md3dDevice->IASetIndexBuffer( m_pTestRenderable->getIB(), DXGI_FORMAT_R32_UINT, 0 ); //Get the Description of the technique, we need this in order to loop through each pass in the technique D3D10_TECHNIQUE_DESC techDesc; m_pTechnique->GetDesc( &techDesc ); //Loop through the passes in the technique for( UINT p = 0; p < techDesc.Passes; ++p ) { //Get a pass at current index and apply it m_pTechnique->GetPassByIndex( p )->Apply( 0 ); //Draw call md3dDevice->DrawIndexed(m_pTestRenderable->getNumOfIndices(),0,0); //m_pD3D10Device->Draw(m_pTestRenderable->getNumOfVerts(),0); } Is there anything I've clearly done wrong or are missing? Spent 2 weeks trying to workout what on earth I've done wrong to no avail. Any insight a fresh pair eyes could give on this would be great.

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• Answers to “What source control system do you use?” (and some winners)

  - by jamiet

  About a month ago I posed a question here on my blog SQL Server devs–what source control system do you use, if any? (answer and maybe win free stuff) in which I asked SQL Server developers to answer the following questions: Are you putting your SQL Server code into a source control system? If so, what source control server software (e.g. TFS, Git, SVN, Mercurial, SourceSafe, Perforce) are you using? What source control client software are you using (e.g. TFS Team Explorer, Tortoise, Red Gate SQL Source Control, Red Gate SQL Connect, Git Bash, etc…)? Why did you make those particular software choices? Any interesting anecdotes to share in regard to your use of source control and SQL Server? I had some really great responses (I highly recommend going and reading them). I promised that the five best, most thought-provoking, responses (as determined by me) would win one of five pairs of licenses for Red Gate SQL Source Control and Red Gate SQL Connect; here are the five that I chose (note that if you responded but did not leave a means of getting in touch then you weren’t considered for one of the prizes – sorry): In general, I don't think the management overhead and licensing cost associated with TFS is worthwhile if all you're doing is using source control. To get value from TFS, at a minimum you need to be using team build, and possibly other stuff as well, such as the sharepoint integration. If that's all you need, then svn with Tortoise would be my first choice. If you want to add build automation later, you can do this with cruisecontrol (is it still called that?), JetBrains, etc. For a long time I thought that Redgate's claims about "bridging the SSMS-VS divide" were a load of hot air, since in my experience anyone who knew what they were doing was using Visual Studio, in particular SSDT and its predecessors. However, on a recent client I was putting in source control for the first time, and I discovered that the "divide" really does exist. That client has ended up using svn with Redgate SQL Source Control, with no build automation, but with scope to add it in the future. Gavin Campbell I think putting the DB under source control is a great idea.  I have issues with the earlier versions of SQL Source Control in that it provides little help in versioning the DB. I think the latest version merges SQL Compare and SQL Source Control together.  Which is how it should have been all along. Sure I have the DB scripts in SVN, but I can't automate DB builds and changes without more tools.  Frankly I'm surprised databases don't have some sort of versioning built into them. Nick Portelli Source control has been immensely useful and saved me from a lot of rework on more than one occasion.  I have learned that you have to be extremely careful checking in data.  Our system is internal only so during the system production run once a week, if there is a problem that I can fix easily(for example, a control table points to a file in the wrong environment), I'll do it directly in production so the run can continue as soon as possible since we have a specified time window.  We do full test runs to minimize this but it has come up once or twice.  We use Red-Gate source control to "push" from the test environment to the production environment.  There have been a couple of occasions where the test environment with the wrong setting was pushed back over the production environment because the change was made only in production.  Gotta keep an eye on that. Alan Dykes Goodness is it manual.  And can be extremely painful at times.  Not only are we running thin, we are constrained on the tools we can get ($$ must mean free).  Certainly no excuse, and a great opportunity to improve my skills by learning new things.  But...  Getting buy in a on a proven process or methodology is hard, takes time, and diverts us from development.  If SQL Source Control is easy to use and proven oh boy could you get some serious fans around here!  Seriously though, as the "accidental dba" of this shop any new ideas / easy to implement tools can make a world of difference in productivity and most importantly accuracy.  Manual = bad. :) John Hennesey (who left his email address) The one thing I would love to know more about is the unique challenges of working with databases as source code - you can store scripts, but are they written as deployment scripts with all the logic about how to apply them to an existing DB? Where is that baseline DB? Where's the data? How does a team share the data and the code? It's a real challenge. Merrill Aldrich Congratulations to the five of you. Red Gate will be in touch with you soon about your free licenses. Thank you to all those that responded. And again, go and check out all the responses – those above are only small proportion from what is a very interesting comment thread. @Jamiet

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• Making your WCF Web Apis to speak in multiple languages

  - by cibrax

  One of the key aspects of how the web works today is content negotiation. The idea of content negotiation is based on the fact that a single resource can have multiple representations, so user agents (or clients) and servers can work together to chose one of them. The http specification defines several “Accept” headers that a client can use to negotiate content with a server, and among all those, there is one for restricting the set of natural languages that are preferred as a response to a request, “Accept-Language”. For example, a client can specify “es” in this header for specifying that he prefers to receive the content in spanish or “en” in english. However, there are certain scenarios where the “Accept-Language” header is just not enough, and you might want to have a way to pass the “accepted” language as part of the resource url as an extension. For example, http://localhost/ProductCatalog/Products/1.es” returns all the descriptions for the product with id “1” in spanish. This is useful for scenarios in which you want to embed the link somewhere, such a document, an email or a page.  Supporting both scenarios, the header and the url extension, is really simple in the new WCF programming model. You only need to provide a processor implementation for any of them. Let’s say I have a resource implementation as part of a product catalog I want to expose with the WCF web apis. [ServiceContract][Export]public class ProductResource{ IProductRepository repository;  [ImportingConstructor] public ProductResource(IProductRepository repository) { this.repository = repository; }  [WebGet(UriTemplate = "{id}")] public Product Get(string id, HttpResponseMessage response) { var product = repository.GetById(int.Parse(id)); if (product == null) { response.StatusCode = HttpStatusCode.NotFound; response.Content = new StringContent(Messages.OrderNotFound); }  return product; }} The Get method implementation in this resource assumes the desired culture will be attached to the current thread (Thread.CurrentThread.Culture). Another option is to pass the desired culture as an additional argument in the method, so my processor implementation will handle both options. This method is also using an auto-generated class for handling string resources, Messages, which is available in the different cultures that the service implementation supports. For example, Messages.resx contains “OrderNotFound”: “Order Not Found” Messages.es.resx contains “OrderNotFound”: “No se encontro orden” The processor implementation bellow tackles the first scenario, in which the desired language is passed as part of the “Accept-Language” header. public class CultureProcessor : Processor<HttpRequestMessage, CultureInfo>{ string defaultLanguage = null;  public CultureProcessor(string defaultLanguage = "en") { this.defaultLanguage = defaultLanguage; this.InArguments[0].Name = HttpPipelineFormatter.ArgumentHttpRequestMessage; this.OutArguments[0].Name = "culture"; }  public override ProcessorResult<CultureInfo> OnExecute(HttpRequestMessage request) { CultureInfo culture = null; if (request.Headers.AcceptLanguage.Count > 0) { var language = request.Headers.AcceptLanguage.First().Value; culture = new CultureInfo(language); } else { culture = new CultureInfo(defaultLanguage); }  Thread.CurrentThread.CurrentCulture = culture; Messages.Culture = culture;  return new ProcessorResult<CultureInfo> { Output = culture }; }}   As you can see, the processor initializes a new CultureInfo instance with the value provided in the “Accept-Language” header, and set that instance to the current thread and the auto-generated resource class with all the messages. In addition, the CultureInfo instance is returned as an output argument called “culture”, making possible to receive that argument in any method implementation   The following code shows the implementation of the processor for handling languages as url extensions.   public class CultureExtensionProcessor : Processor<HttpRequestMessage, Uri>{ public CultureExtensionProcessor() { this.OutArguments[0].Name = HttpPipelineFormatter.ArgumentUri; }  public override ProcessorResult<Uri> OnExecute(HttpRequestMessage httpRequestMessage) { var requestUri = httpRequestMessage.RequestUri.OriginalString;  var extensionPosition = requestUri.LastIndexOf(".");  if (extensionPosition > -1) { var extension = requestUri.Substring(extensionPosition + 1);  var query = httpRequestMessage.RequestUri.Query;  requestUri = string.Format("{0}?{1}", requestUri.Substring(0, extensionPosition), query); ;  var uri = new Uri(requestUri);  httpRequestMessage.Headers.AcceptLanguage.Clear();  httpRequestMessage.Headers.AcceptLanguage.Add(new StringWithQualityHeaderValue(extension));  var result = new ProcessorResult<Uri>();  result.Output = uri;  return result; }  return new ProcessorResult<Uri>(); }} The last step is to inject both processors as part of the service configuration as it is shown bellow, public void RegisterRequestProcessorsForOperation(HttpOperationDescription operation, IList<Processor> processors, MediaTypeProcessorMode mode){ processors.Insert(0, new CultureExtensionProcessor()); processors.Add(new CultureProcessor());} Once you configured the two processors in the pipeline, your service will start speaking different languages :). Note: Url extensions don’t seem to be working in the current bits when you are using Url extensions in a base address. As far as I could see, ASP.NET intercepts the request first and tries to route the request to a registered ASP.NET Http Handler with that extension. For example, “http://localhost/ProductCatalog/products.es” does not work, but “http://localhost/ProductCatalog/products/1.es” does.

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• Vacations on Rodrigues 2014

  And now something completely different compared to the usual technical or community related articles here on this blog. Yes, this time I'm writing some lines on my (and my family's) activities during our long weekend stay on Rodrigues. So, please bear with me, it's eventually a bit more personal... Grab a soda, some popcorn and a cosy place to continue to read. var googleAlbumLink = "https://plus.google.com/photos/117698191428446859536/albums/6047895311458281985"; //optional----------------------- var mySlideWidth = 580; var mySlideHeight = 340; var mySlideDelay = 7000; //delay in milliseconds Special promotions during school holidays Originally, our children started to ask more frequently about going on the plane again. Obviously, after their aunty from Germany was around during May, they were really eager to travel again. So, we decided that it might be a great opportunity to book some vacations during their school holidays. And just in time the local hotels and hotel groups started to advertise their special promotions for citizens and residents. After collecting multiple brochures over several days, we got attracted by various hotel packages on Rodrigues - most interestingly the expenses for the stay and flight ticket were less compared to other resorts here on the main island. As we have been to Rodrigues already back in 2008, we followed up on this idea and got in touch with a couple travel agencies. Well, I have to report that you should be really careful about the promotions from some of them. We had a very negative experience with Shamal Travel Agency in Quatre Bornes regarding their adverts and the actual price levels and age definition for children. Please, stay away from them if you are interested in transparent cost and services. Anyway, after some arrangements with two other close families we managed to confirm our stay at the Cotton Bay Hotel in Rodrigues. Given the fact that we already stayed there, and the hotel has been renovated recently, and it is under new management all looked very promising and relaxed for our vacation. Counting the days... As we already booked in July our children were counting down the days. And it got more interesting as soon as they were on school holidays finally. Well, the day arrived and waking them up at 2:30 hrs wasn't a problem after all. Quite the opposite it was fascinating for us parents to watch them waiting for the transport and later on during the airport transfer. Despite the early hours both didn't fall asleep and it was all so exciting. We are taking the plane! Well organised by the Cotton Bay Hotel Honestly, it was a breeze and a smooth ride during our stay at the hotel. From the airport transfer, the cleanliness of our bungalow, the organisation of our day trips, and the SPA - all very well and enjoyable. The children had great fun, and although it was a bit too windy to plunge into the pool they had a lot of fun with other activities on the beach and at the Kid's Club. Oh, and we had our private petting zoo with cows, sheep and goats just close to the terrace. Some of us went to check out the SPA facilities and I have to admit that the services regarding Hammam and Sauna are better than at some other hotels in Mauritius. I don't know after how many months or years I was once again enjoying a very hot sauna. Little draw-back but nothing to worry about... There is no cold water or at least ice cubes to cool down the body, but hey there was a nice breeze coming over the hills. Some day trips to mention Based on a friend's recommendation we walked to a "restaurant" called Chez Solange & Robert. Hahaha, restaurant is widely stretched in this case, as we enjoyed a great BBQ with fresh lobster, whole fish, and pieces of chicken breast in an open cottage. Just some wooden structure covered with dried palm leaves on the roof - island feeling pure! The other day we went to the Giant Tortoise & Cave Reserve Francois Leguat to observe the giant Aldabra turtles and to visit the Grande Caverne. The biggest limestone cave on the island. Compared to our last visit this was a novelty after checking out the Caverne Partate. The formations of stalactites and stalagmites are very impressive and imaginative. Our guide had lots of funny terms and despite the low light conditions the kids had a great time wandering around on the narrow wooden paths and stairs. And last but not least, we decided to check out the Tyrodrig zip lines... Everyone was allowed to join the trip through the air, and our little ones stayed close to our field guides. But finally went on their own on the very last traversal. Puuuh, it was astounishing to glide over the valley, and for sure something to repeat next time. Impressions of our vacation on Rodrigues 2014   Next stay has been discussed already Oh yes, Rodrigues baby! We are going to come again! Tentative dates have been discussed already and now it's up to us to earn enough our next holiday on that wonderful remote piece of paradise. Eventually, a little bit longer than this time. We'll see...

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• How to Answer a Stupid Interview Question the Right Way

  - by AjarnMark

  Have you ever been asked a stupid question during an interview; one that seemed to have no relation to the job responsibilities at all?  Tech people are often caught off-guard by these apparently irrelevant questions, but there is a way you can turn these to your favor.  Here is one idea. While chatting with a couple of folks between sessions at SQLSaturday 43 last weekend, one of them expressed frustration over a seemingly ridiculous and trivial question that she was asked during an interview, and she believes it cost her the job opportunity.  The question, as I remember it being described was, “What is the largest byte measurement?”.  The candidate made up a guess (“zetabyte”) during the interview, which is actually closer than she may have realized.  According to Wikipedia, there is a measurement known as zettabyte which is 10^21, and the largest one listed there is yottabyte at 10^24. My first reaction to this question was, “That’s just a hiring manager that doesn’t really know what they’re looking for in a candidate.  Furthermore, this tells me that this manager really does not understand how to build a team.”  In most companies, team interaction is more important than uber-knowledge.  I didn’t ask, but this could also be another geek on the team trying to establish their Alpha-Geek stature.  I suppose that there are a few, very few, companies that can build their businesses on hiring only the extreme alpha-geeks, but that certainly does not represent the majority of businesses in America. My friend who was there suggested that the appropriate response to this silly question would be, “And how does this apply to the work I will be doing?” Of course this is an understandable response when you’re frustrated because you know you can handle the technical aspects of the job, and it seems like the interviewer is just being silly.  But it is also a direct challenge, which may not be the best approach in interviewing.  I do have to admit, though, that there are those folks who just won’t respect you until you do challenge them, but again, I don’t think that is the majority. So after some thought, here is my suggestion: “Well, I know that there are petabytes and exabytes and things even larger than that, but I haven’t been keeping up on my list of Greek prefixes that have not yet been used, so I would have to look up the exact answer if you need it.  However, I have worked with databases as large as 30 Terabytes.  How big are the largest databases here at X Corporation?”  Perhaps with a follow-up of, “Typically, what I have seen in companies that have databases of your size, is that the three biggest challenges they face are: A, B, and C.  What would you say are the top 3 concerns that you would like the person you hire to be able to address?…Here is how I have dealt with those concerns in the past (or ‘Here is how I would tackle those issues for you…’).” Wait! What just happened?!  We took a seemingly irrelevant and frustrating question and turned it around into an opportunity to highlight our relevant skills and guide the conversation back in a direction more to our liking and benefit.  In more generic terms, here is what we did: Admit that you don’t know the specific answer off the top of your head, but can get it if it’s truly important to the company. Maybe for some reason it really is important to them. Mention something similar or related that you do know, reassuring them that you do have some knowledge in that subject area. Draw a parallel to your past work experience. Ask follow-up questions about the company’s specific needs and discuss how you can fulfill those. This type of thing requires practice and some forethought.  I didn’t come up with this answer until a day later, which is too late when you’re interviewing.  I still think it is silly for an interviewer to ask something like that, but at least this is one way to spin it to your advantage while you consider whether you really want to work for someone who would ask a thing like that.  Remember, interviewing is a two-way process.  You’re deciding whether you want to work there just as much as they are deciding whether they want you. There is always the possibility that this was a calculated maneuver on the part of the hiring manager just to see how quickly you think on your feet and how you handle stupid questions.  Maybe he knows something about the work environment and he’s trying to gauge whether you’ll actually fit in okay.  And if that’s the case, then the above response still works quite well.

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• Windows Workflow Foundation (WF) and things I wish were more intuitive

  - by pjohnson

  I've started using Windows Workflow Foundation, and so far ran into a few things that aren't incredibly obvious. Microsoft did a good job of providing a ton of samples, which is handy because you need them to get anywhere with WF. The docs are thin, so I've been bouncing between samples and downloadable labs to figure out how to implement various activities in a workflow. Code separation or not? You can create a workflow and activity in Visual Studio with or without code separation, i.e. just a .cs "Component" style object with a Designer.cs file, or a .xoml XML markup file with code behind (beside?) it. Absence any obvious advantage to one or the other, I used code separation for workflows and any complex custom activities, and without code separation for custom activities that just inherit from the Activity class and thus don't have anything special in the designer. So far, so good. Workflow Activity Library project type - What's the point of this separate project type? So far I don't see much advantage to keeping your custom activities in a separate project. I prefer to have as few projects as needed (and no fewer). The Designer's Toolbox window seems to find your custom activities just fine no matter where they are, and the debugging experience doesn't seem to be any different. Designer Properties - This is about the designer, and not specific to WF, but nevertheless something that's hindered me a lot more in WF than in Windows Forms or elsewhere. The Properties window does a good job of showing you property values when you hover the mouse over the values. But they don't do the same to find out what a control's type is. So maybe if I named all my activities "x1" and "x2" instead of helpful self-documenting names like "listenForStatusUpdate", then I could easily see enough of the type to determine what it is, but any names longer than those and all I get of the type is "System.Workflow.Act" or "System.Workflow.Compone". Even hitting the dropdown doesn't expand any wider, like the debugger quick watch "smart tag" popups do when you scroll through members. The only way I've found around this in VS 2008 is to widen the Properties dialog, losing precious designer real estate, then shrink it back down when you're done to see what you were doing. Really? WF Designer - This is about the designer, and I believe is specific to WF. I should be able to edit the XML in a .xoml file, or drag and drop using the designer. With WPF (at least in VS 2010 Ultimate), these are side by side, and changes to one instantly update the other. With WF, I have to right-click on the .xoml file, choose Open With, and pick XML Editor to edit the text. It looks like this is one way where WF didn't get the same attention WPF got during .NET Fx 3.0 development. Service - In the WF world, this is simply a class that talks to the workflow about things outside the workflow, not to be confused with how the term "service" is used in every other context I've seen in the Windows and .NET world, i.e. an executable that waits for events or requests from a client and services them (Windows service, web service, WCF service, etc.). ListenActivity - Such a great concept, yet so unintuitive. It seems you need at least two branches (EventDrivenActivity instances), one for your positive condition and one for a timeout. The positive condition has a HandleExternalEventActivity, and the timeout has a DelayActivity followed by however you want to handle the delay, e.g. a ThrowActivity. The timeout is simple enough; wiring up the HandleExternalEventActivity is where things get fun. You need to create a service (see above), and an interface for that service (this seems more complex than should be necessary--why not have activities just wire to a service directly?). And you need to create a custom EventArgs class that inherits from ExternalDataEventArgs--you can't create an ExternalDataEventArgs event handler directly, even if you don't need to add any more information to the event args, despite ExternalDataEventArgs not being marked as an abstract class, nor a compiler error nor warning nor any other indication that you're doing something wrong, until you run it and find that it always times out and get to check every place mentioned here to see why. Your interface and service need an event that consumes your custom EventArgs class, and a method to fire that event. You need to call that method from somewhere. Then you get to hope that you did everything just right, or that you can step through code in the debugger before your Delay timeout expires. Yes, it's as much fun as it sounds. TransactionScopeActivity - I had the bright idea of putting one in as a placeholder, then filling in the database updates later. That caused this error: The workflow hosting environment does not have a persistence service as required by an operation on the workflow instance "[GUID]". ...which is about as helpful as "Object reference not set to an instance of an object" and even more fun to debug. Google led me to this Microsoft Forums hit, and from there I figured out it didn't like that the activity had no children. Again, a Validator on TransactionScopeActivity would have pointed this out to me at design time, rather than handing me a nearly useless error at runtime. Easily enough, I disabled the activity and that fixed it. I still see huge potential in my work where WF could make things easier and more flexible, but there are some seriously rough edges at the moment. Maybe I'm just spoiled by how much easier and more intuitive development elsewhere in the .NET Framework is.

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• Using SQL Source Control with Fortress or Vault &ndash; Part 1

  - by AjarnMark

  I am fanatical when it comes to managing the source code for my company.  Everything that we build (in source form) gets put into our source control management system.  And I’m not just talking about the UI and middle-tier code written in C# and ASP.NET, but also the back-end database stuff, which at times has been a pain.  We even script out our Scheduled Jobs and keep a copy of those under source control. The UI and middle-tier stuff has long been easy to manage as we mostly use Visual Studio which has integration with source control systems built in.  But the SQL code has been a little harder to deal with.  I have been doing this for many years, well before Microsoft came up with Data Dude, so I had already established a methodology that, while not as smooth as VS, nonetheless let me keep things well controlled, and allowed doing my database development in my tool of choice, Query Analyzer in days gone by, and now SQL Server Management Studio.  It just makes sense to me that if I’m going to do database development, let’s use the database tool set.  (Although, I have to admit I was pretty impressed with the demo of Juneau that Don Box did at the PASS Summit this year.)  So as I was saying, I had developed a methodology that worked well for us (and I’ll probably outline in a future post) but it could use some improvement. When Solutions and Projects were first introduced in SQL Management Studio, I thought we were finally going to get our same experience that we have in Visual Studio.  Well, let’s say I was underwhelmed by Version 1 in SQL 2005, and apparently so were enough other people that by the time SQL 2008 came out, Microsoft decided that Solutions and Projects would be deprecated and completely removed from a future version.  So much for that idea. Then I came across SQL Source Control from Red-Gate.  I have used several tools from Red-Gate in the past, including my favorites SQL Compare, SQL Prompt, and SQL Refactor.  SQL Prompt is worth its weight in gold, and the others are great, too.  Earlier this year, we upgraded from our earlier product bundles to the new Developer Bundle, and in the process added SQL Source Control to our collection.  I thought this might really be the golden ticket I was looking for.  But my hopes were quickly dashed when I discovered that it only integrated with Microsoft Team Foundation Server and Subversion as the source code repositories.  We have been using SourceGear’s Vault and Fortress products for years, and I wholeheartedly endorse them.  So I was out of luck for the time being, although there were a number of people voting for Vault/Fortress support on their feedback forum (as did I) so I had hope that maybe next year I could look at it again. But just a couple of weeks ago, I was pleasantly surprised to receive notice in my email that Red-Gate had an Early Access version of SQL Source Control that worked with Vault and Fortress, so I quickly downloaded it and have been putting it through its paces.  So far, I really like what I see, and I have been quite impressed with Red-Gate’s responsiveness when I have contacted them with any issues or concerns that I have had.  I have had several communications with Gyorgy Pocsi at Red-Gate and he has been immensely helpful and responsive. I must say that development with SQL Source Control is very different from what I have been used to.  This post is getting long enough, so I’ll save some of the details for a separate write-up, but the short story is that in my regular mode, it’s all about the script files.  Script files are King and you dare not make a change to the database other than by way of a script file, or you are in deep trouble.  With SQL Source Control, you make your changes to your development database however you like.  I still prefer writing most of my changes in T-SQL, but you can also use any of the GUI functionality of SSMS to make your changes, and SQL Source Control “manages” the script for you.  Basically, when you first link your database to source control, the tool generates scripts for every primary object (tables and their indexes are together in one script, not broken out into separate scripts like DB Projects do) and those scripts are checked into your source control.  So, if you needed to, you could still do a GET from your source control repository and build the database from scratch.  But for the day-to-day work, SQL Source Control uses the same technique as SQL Compare to determine what changes have been made to your development database and how to represent those in your repository scripts.  I think that once I retrain myself to just work in the database and quit worrying about having to find and open the right script file, that this will actually make us more efficient. And for deployment purposes, SQL Source Control integrates with the full SQL Compare utility to produce a synchronization script (or do a live sync).  This is similar in concept to Microsoft’s DACPAC, if you’re familiar with that. If you are not currently keeping your database development efforts under source control, definitely examine this tool.  If you already have a methodology that is working for you, then I still think this is worth a review and comparison to your current approach.  You may find it more efficient.  But remember that the version which integrates with Vault/Fortress is still in pre-release mode, so treat it with a little caution.  I have found it to be fairly stable, but there was one bug that I found which had inconvenient side-effects and could have really been frustrating if I had been running this on my normal active development machine.  However, I can verify that that bug has been fixed in a more recent build version (did I mention Red-Gate’s responsiveness?).

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• Monitoring your WCF Web Apis with AppFabric

  - by cibrax

  The other day, Ron Jacobs made public a template in the Visual Studio Gallery for enabling monitoring capabilities to any existing WCF Http service hosted in Windows AppFabric. I thought it would be a cool idea to reuse some of that for doing the same thing on the new WCF Web Http stack. Windows AppFabric provides a dashboard that you can use to dig into some metrics about the services usage, such as number of calls, errors or information about different events during a service call. Those events not only include information about the WCF pipeline, but also custom events that any developer can inject and make sense for troubleshooting issues.      This monitoring capabilities can be enabled on any specific IIS virtual directory by using the AppFabric configuration tool or adding the following configuration sections to your existing web app, <system.serviceModel> <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" /> <diagnostics etwProviderId="3e99c707-3503-4f33-a62d-2289dfa40d41"> <endToEndTracing propagateActivity="true" messageFlowTracing="true" /> </diagnostics> <behaviors> <serviceBehaviors> <behavior name=""> <etwTracking profileName="EndToEndMonitoring Tracking Profile" /> </behavior> </serviceBehaviors> </behaviors> </system.serviceModel>   <microsoft.applicationServer> <monitoring> <default enabled="true" connectionStringName="ApplicationServerMonitoringConnectionString" monitoringLevel="EndToEndMonitoring" /> </monitoring> </microsoft.applicationServer> Bad news is that none of the configuration above can be easily set on code by using the new configuration model for WCF Web stack.  A good thing is that you easily disable it in the configuration when you no longer need it, and also uses ETW, a general-purpose and high-speed tracing facility provided by the operating system (it’s part of the windows kernel). By adding that configuration section, AppFabric will start monitoring your service automatically and providing some basic event information about the service calls. You need some custom code for injecting custom events in the monitoring data. What I did here is to copy and refactor the “WCFUserEventProvider” class provided as sample in the Ron’s template to make it more TDD friendly when using IoC. I created a simple interface “ILogger” that any service (or resource) can use to inject custom events or monitoring information in the AppFabric database. public interface ILogger { bool WriteError(string name, string format, params object[] args); bool WriteWarning(string name, string format, params object[] args); bool WriteInformation(string name, string format, params object[] args); } The “WCFUserEventProvider” class implements this interface by making possible to send the events to the AppFabric monitoring database. The service or resource implementation can receive an “ILogger” as part of the constructor. [ServiceContract] [Export] public class OrderResource { IOrderRepository repository; ILogger logger;   [ImportingConstructor] public OrderResource(IOrderRepository repository, ILogger logger) { this.repository = repository; this.logger = logger; }   [WebGet(UriTemplate = "{id}")] public Order Get(string id, HttpResponseMessage response) { var order = this.repository.All.FirstOrDefault(o => o.OrderId == int.Parse(id, CultureInfo.InvariantCulture)); if (order == null) { response.StatusCode = HttpStatusCode.NotFound; response.Content = new StringContent("Order not found"); }   this.logger.WriteInformation("Order Requested", "Order Id {0}", id);   return order; } } The example above uses “MEF” as IoC for injecting a repository and the logger implementation into the service. You can also see how the logger is used to write an information event in the monitoring database. The following image illustrates how the custom event is injected and the information becomes available for any user in the dashboard. An issue that you might run into and I hope the WCF and AppFabric teams fixed soon is that any WCF service that uses friendly URLs with ASP.NET routing does not get listed as a available service in the WCF services tab in the AppFabric console. The complete example is available to download from here.

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