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• Cross-Platform Google Chrome App Installer

  - by Volomike

  I have fallen in love with the Google Chrome App way of making an "app" (and extensions as well). What kind of installer would you recommend (free and/or cheap is preferred) that is cross-platform (Mac, Windows 2000+, Linux (Ubuntu, Debian, Suse, Redhat, or derivatives)) and lets me deploy Google Chrome Apps on workstations? It would need to let me deploy Google Chrome, or update Google Chrome to a particular version, as necessary, in order for my app to work.

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• Subscription service or software to handle a Magazine's PDF

  - by Paolo

  I'm looking for an installable or hosted software (service) to handle the process of public users subscribing to the Magazine and receiving the PDF automatically upon an admin upload the new one. The system will have to: handle the money part (PayPal&Co. are OK) let user buy old issues of the Magazine warn user on subscription expiring, etc. PDF stamping and WordPress integration (user credential sharing, page access of subriscrebed goods, etc) will be a big plus.

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• Oracle VM VirtualBox 3.2.4 is released!

  - by Fat Bloke

  Thanks to all in the community who spotted a couple of regressions with 3.2.2. We couldn't let them pass and so have updated VirtualBox to version 3.2.4 to fix them. - FB

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• SQL SERVER – Validating Spatial Object with IsValidDetailed Function

  - by pinaldave

  What do you prefer – error or warning indicating error may happen with the reason for the error. While writing the previous statement I remember the movie “Minory Report”. This blog post is not about minority report but I will still cover the concept in a single statement “Let us predict the future and prevent the crime which is about to happen in future”. (Please feel free to correct me if I am wrong about the movie concept, I really do not want to hurt your sentiment if you are dedicated fan). Let us switch to the SQL Server world. Spatial data types are interesting concepts. I love writing about spatial data types because it allows me to be creative with shapes (just like toddlers). When working with Spatial Datatypes it is all good when the spatial object works fine. However, when the spatial object has issue or it is created with invalid coordinates it used to give a simple error that there is an issue with the object but did not provide much information. This made it very difficult to debug. If this spatial object was used in the big procedure and while this big procedural error out because of the invalid spatial object, it is indeed very difficult to debug it. I always wished that the more information provided regarding what is the problem with spatial datatype. SQL Server 2012 has introduced the new function IsValidDetailed(). This function has made my life very easy. In simple words this function will check if the spatial object passed is valid or not. If it is valid it will give information that it is valid. If the spatial object is not valid it will return the answer that it is not valid and the reason for the same. This makes it very easy to debug the issue and make the necessary correction. DECLARE @p GEOMETRY = 'Polygon((2 2, 6 6, 4 2, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 3 3, 4 4, 5 5, 6 6, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 4 4, 4 2, 2 3, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'LINESTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO Here is the resultset of the above query. You can see any valid query and some invalid query. If the query is invalid it also demonstrates the reason along with the error message. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database, SQL Spatial

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• Altering a Column Which has a Default Constraint

  - by Dinesh Asanka

  Setting up a default column is a common task for  developers.  But, are we naming those default constraints explicitly? In the below  table creation, for the column, sys_DateTime the default value Getdate() will be allocated. CREATE TABLE SampleTable (ID int identity(1,1), Sys_DateTime Datetime DEFAULT getdate() ) We can check the relevant information from the system catalogs from following query. SELECT sc.name TableName, dc.name DefaultName, dc.definition, OBJECT_NAME(dc.parent_object_id) TableName, dc.is_system_named  FROM sys.default_constraints dc INNER JOIN sys.columns sc ON dc.parent_object_id = sc.object_id AND dc.parent_column_id = sc.column_id and results would be: Most of the above columns are self-explanatory. The last column, is_system_named, is to identify whether the default name was given by the system. As you know, in the above case, since we didn’t provide  any default name, the  system will generate a default name for you. But the problem with these names is that they can differ from environment to environment.  If example if I create this table in different table the default name could be DF__SampleTab__Sys_D__7E6CC920 Now let us create another default and explicitly name it: CREATE TABLE SampleTable2 (ID int identity(1,1), Sys_DateTime Datetime )   ALTER TABLE SampleTable2 ADD CONSTRAINT DF_sys_DateTime_Getdate DEFAULT( Getdate()) FOR Sys_DateTime If we run the previous query again we will be returned the below output. And you can see that last created default name has 0 for is_system_named. Now let us say I want to change the data type of the sys_DateTime column to something else: ALTER TABLE SampleTable2 ALTER COLUMN Sys_DateTime Date This will generate the below error: Msg 5074, Level 16, State 1, Line 1 The object ‘DF_sys_DateTime_Getdate’ is dependent on column ‘Sys_DateTime’. Msg 4922, Level 16, State 9, Line 1 ALTER TABLE ALTER COLUMN Sys_DateTime failed because one or more objects access this column. This means, you need to drop the default constraint before altering it: ALTER TABLE [dbo].[SampleTable2] DROP CONSTRAINT [DF_sys_DateTime_Getdate] ALTER TABLE SampleTable2 ALTER COLUMN Sys_DateTime Date   ALTER TABLE [dbo].[SampleTable2] ADD CONSTRAINT [DF_sys_DateTime_Getdate] DEFAULT (getdate()) FOR [Sys_DateTime] If you have a system named default constraint that can differ from environment to environment and so you cannot drop it as before, you can use the below code template: DECLARE @defaultname VARCHAR(255) DECLARE @executesql VARCHAR(1000)   SELECT @defaultname = dc.name FROM sys.default_constraints dc INNER JOIN sys.columns sc ON dc.parent_object_id = sc.object_id AND dc.parent_column_id = sc.column_id WHERE OBJECT_NAME (parent_object_id) = 'SampleTable' AND sc.name ='Sys_DateTime' SET @executesql = 'ALTER TABLE SampleTable DROP CONSTRAINT ' + @defaultname EXEC( @executesql) ALTER TABLE SampleTable ALTER COLUMN Sys_DateTime Date ALTER TABLE [dbo].[SampleTable] ADD DEFAULT (Getdate()) FOR [Sys_DateTime]

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• The polls are closed!!

  Greetings Everyone, This is just a quick note to let you know that the election for the two OpenSocial Board Community Representatives is now officially closed. We will...

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• VS 2010 ALM Whitepapers &ndash; link from Neno Loje

  - by johndoucette

  Overview of Visual Studio ALM Whitepapers by Microsoft Overview Visual Studio 2010 Quick Reference Guidance Installation, Configuration & Administration Team Foundation Installation Guide for Visual Studio Team System 2010 Administration Guide for Microsoft Visual Studio 2010 Team Foundation Server Visual Studio 2010 TFS Upgrade Guide Visual Studio 2010 and Team Foundation Server 2010 VM Factory TFS Integration Platform Visual Studio 2010 Licensing White Paper Requirements Visual Studio 2010 Team Foundation Server Requirements Management Guidance Version Control & Configuration Management Visual Studio TFS Branching Guide 2010 Some guide or whitepaper missing? Let me know!

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• Customize Chrome for Better Browsing

  <b>Linux Magazine:</b> "Google Chrome has only had extensions available for a few months, but it already has a great collection of add-ons that will boost your browsing experience. We look at a handful of extensions that let you manage tabs effectively, learn more about the sites you browse, and read feeds with panache."

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• Internal Mutation of Persistent Data Structures

  - by Greg Ros

  To clarify, when I mean use the terms persistent and immutable on a data structure, I mean that: The state of the data structure remains unchanged for its lifetime. It always holds the same data, and the same operations always produce the same results. The data structure allows Add, Remove, and similar methods that return new objects of its kind, modified as instructed, that may or may not share some of the data of the original object. However, while a data structure may seem to the user as persistent, it may do other things under the hood. To be sure, all data structures are, internally, at least somewhere, based on mutable storage. If I were to base a persistent vector on an array, and copy it whenever Add is invoked, it would still be persistent, as long as I modify only locally created arrays. However, sometimes, you can greatly increase performance by mutating a data structure under the hood. In more, say, insidious, dangerous, and destructive ways. Ways that might leave the abstraction untouched, not letting the user know anything has changed about the data structure, but being critical in the implementation level. For example, let's say that we have a class called ArrayVector implemented using an array. Whenever you invoke Add, you get a ArrayVector build on top of a newly allocated array that has an additional item. A sequence of such updates will involve n array copies and allocations. Here is an illustration: However, let's say we implement a lazy mechanism that stores all sorts of updates -- such as Add, Set, and others in a queue. In this case, each update requires constant time (adding an item to a queue), and no array allocation is involved. When a user tries to get an item in the array, all the queued modifications are applied under the hood, requiring a single array allocation and copy (since we know exactly what data the final array will hold, and how big it will be). Future get operations will be performed on an empty cache, so they will take a single operation. But in order to implement this, we need to 'switch' or mutate the internal array to the new one, and empty the cache -- a very dangerous action. However, considering that in many circumstances (most updates are going to occur in sequence, after all), this can save a lot of time and memory, it might be worth it -- you will need to ensure exclusive access to the internal state, of course. This isn't a question about the efficacy of such a data structure. It's a more general question. Is it ever acceptable to mutate the internal state of a supposedly persistent or immutable object in destructive and dangerous ways? Does performance justify it? Would you still be able to call it immutable? Oh, and could you implement this sort of laziness without mutating the data structure in the specified fashion?

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• SQL SERVER – Introduction to Function SIGN

  - by pinaldave

  Yesterday I received an email from a friend asking how do SIGN function works. Well SIGN Function is very fundamental function. It will return the value 1, -1 or 0. If your value is negative it will return you negative -1 and if it is positive it will return you positive +1. Let us start with a simple small example. DECLARE @IntVal1 INT, @IntVal2 INT,@IntVal3 INT DECLARE @NumVal1 DECIMAL(4,2), @NumVal2 DECIMAL(4,2),@NumVal3 DECIMAL(4,2) SET @IntVal1 = 9; SET @IntVal2 = -9; SET @IntVal3 = 0; SET @NumVal1 = 9.0; SET @NumVal2 = -9.0; SET @NumVal3 = 0.0; SELECT SIGN(@IntVal1) IntVal1,SIGN(@IntVal2) IntVal2,SIGN(@IntVal3) IntVal3 SELECT SIGN(@NumVal1) NumVal1,SIGN(@NumVal2) NumVal2,SIGN(@NumVal2) NumVal3   The above function will give us following result set. You will notice that when there is positive value the function gives positive values and if the values are negative it will return you negative values. Also you will notice that if the data type is  INT the return value is INT and when the value passed to the function is Numeric the result also matches it. Not every datatype is compatible with this function.  Here is the quick look up of the return types. bigint -> bigint int/smallint/tinyint -> int money/smallmoney -> money numeric/decimal -> numeric/decimal everybody else -> float What will be the best example of the usage of this function that you will not have to use the CASE Statement. Here is example of CASE Statement usage and the same replaced with SIGN function. USE tempdb GO CREATE TABLE TestTable (Date1 SMALLDATETIME, Date2 SMALLDATETIME) INSERT INTO TestTable (Date1, Date2) SELECT '2012-06-22 16:15', '2012-06-20 16:15' UNION ALL SELECT '2012-06-24 16:15', '2012-06-22 16:15' UNION ALL SELECT '2012-06-22 16:15', '2012-06-22 16:15' GO -- Using Case Statement SELECT CASE WHEN DATEDIFF(d,Date1,Date2) > 0 THEN 1 WHEN DATEDIFF(d,Date1,Date2) < 0 THEN -1 ELSE 0 END AS Col FROM TestTable GO -- Using SIGN Function SELECT SIGN(DATEDIFF(d,Date1,Date2)) AS Col FROM TestTable GO DROP TABLE TestTable GO This was interesting blog post for me to write. Let me know your opinion. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Calling methods on Objects

  - by Mashael

  Let's say we have a class called 'Automobile' and we have an instance of that class called 'myCar'. I would like to ask why do we need to put the values that our methods return in a variable for the object? Why just don't we call the method? For example: Why should we write: string message = myCar.SpeedMessage(); Console.WriteLine(message); instead of: Console.WriteLine(myCar.SpeedMessage());

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• Running 12.04 on a Dell Inspiron 1545 having random system lockups

  - by Kris

  I just reinstalled a fresh 12.04 because I couldn't even get booted on my previous installation anymore. I just installed 8GB of ram on this laptop, but the problem happened even before this, and all I have installed in this run on Ubuntu is: ia32libs, Oracle JDK7 and the 32bit JRE junipernc jupiter The laptop has never been used very heavily, so could someone get back to me on this, let me know what further information you need about my machine, or files to upload. Thanks!

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• Easy (and amazing) Debian for the N900

  <b>Open Attitude:</b> "By the time you read this my Nokia N900 will be packed up and on its way back to the kind folks who let me test it. As a last hurrah I spent my evening yesterday seeing how far I could push it; the results are fairly spectacular..."

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• Customizing Flowcharts in Oracle Tutor

  - by [email protected]

  Today we're going to look at how you can customize the flowcharts within Oracle Tutor procedures, and how you can share those changes with other authors within your company. Here is an image of a flowchart within a Tutor procedure with the default size and color scheme. You may want to change the size of your flowcharts as your end-users might have larger screens or need larger fonts. To change the size and number of columns, navigate to Tutor Author Author Options Flowcharts. The default is to have 4 columns appear in each flowchart, but, if I change it to six, my end-users will see a denser flowchart. This might be too dense for my end-users, so I will change it to 5 columns, and I will also deselect the option to have separate task boxes. Now let's look at how to customize the colors. Within the Flowchart options dialog, there is a button labeled "Colors." This brings up a dialog box of every object on a Tutor flowchart, and I can modify the color of each object, as well as the text within the object. If I click on the background, the "page" object appears in the Item field, and now I can customize the color and the title text by selecting Select Fill Color and/or Select Text Color. A dialog box with color choices appears. If I select Define Custom Colors, I can make my selections even more precise. Each time I change the color of an object, it appears in the selection screen. When the flowchart customization is finished, I can save my changes by naming the scheme. Although the color scheme I have chosen is rather silly looking, perhaps I want others to give me their feedback and make changes as they wish. I can share the color scheme with them by copying the FCP.INI file in the Tutor\Author directory into the same directory on their systems. If the other users have color schemes that they do not want to lose, they can copy the relevant lines from the FCP.INI file into their file. If I flowchart my document with the new scheme, I can see how it looks within the document. Sometimes just one or two changes to the default scheme are enough to customize the flowchart to your company's color palette. I have seen customers who have only changed the Start object to green and the End object to red, and I've seen another customer who changed every object to some variant of black and orange. Experiment! And let us know how you have customized your flowcharts. Mary R. Keane Senior Development Director, Oracle Tutor

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• What do you do when you encounter an idiotic interview question?

  - by Senthil

  I was interviewing with a "too proud of my java skills"-looking person. He asked me "What is your knowledge on Java IO classes.. say.. hash maps?" He asked me to write a piece of java code on paper - instantiate a class and call one of the instance's methods. When I was done, he said my program wouldn't run. After 5 minutes of serious thinking, I gave up and asked why. He said I didn't write a main function so it wouldn't run. ON PAPER. [I am too furious to continue with the stupidity...] Believe me it wasn't trick questions or a psychic or anger management evaluation thing. I can tell from his face, he was proud of these questions. That "developer" was supposed to "judge" the candidates. I can think of several things: Hit him with a chair (which I so desperately wanted to) and walk out. Simply walk out. Ridicule him saying he didn't make sense. Politely let him know that he didn't make sense and go on to try and answer the questions. Don't tell him anything, but simply go on to try and answer the questions. So far, I have tried just 4 and 5. It hasn't helped. Unfortunately many candidates seem to do the same and remain polite but this lets these kind of "developers" just keep ascending up the corporate ladder, gradually getting the capacity to pi** off more and more people. How do you handle these interviewers without bursting your veins? What is the proper way to handle this, yet maintain your reputation if other potential employers were to ever get to know what happened here? Is there anything you can do or should you even try to fix this? P.S. Let me admit that my anger has been amplified many times by the facts: He was smiling like you wouldn't believe. I got so many (20 or so) calls from that company the day before, asking me to come to the interview, that I couldn't do any work that day. I wasted a paid day off.

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• RewriteRules targeting a directory result in a gratuitous redirect

  - by MapDot

  I have a standard CMS-like RewriteRule set up in my .htaccess: RewriteRule ^(.+)$ index.php?slug=$1 Let's say I have a directory called "foo" in the root directory. For some reason, if you hit the page it causes a redirect: http://www.mysite.com/foo -- http://www.mysite.com/foo?slug=foo Removing the directory fixes the problem, but unfortunately, it's not an option. Does anyone know of a workaround?

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• Warp GameObject Size When Entering/Leaving Area

  - by Julian

  Below I have an image describing the desired functionality I am going for. Let's say you control a square and when you move this square into a given area, any part of your rigidbody/model inside of the area will be magnified upon entering and shrunk upon leaving. So now you more or less are made up of two rectangles, one small and one large. What would be an elegant approach towards achieving this effect?

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• Link between tests and user stories

  - by Sardathrion

  I have not see these links explicitly stated in the Agile literature I have read. So, I was wondering if this approach was correct: Let a story be defined as "In order to [RESULT], [ROLE] needs to [ACTION]" then RESULT generates system tests. ROLE generates acceptance tests. ACTION generates component and unit tests. Where the definitions are the ones used in xUnit Patterns which to be fair are fairly standard. Is this a correct interpretation or did I misunderstand something?

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• From J2EE to Java EE: what has changed?

  - by Bruno.Borges

  See original @Java_EE tweet on 29 May 2014 Yeap, it has been 8 years since the term J2EE was replaced, and still some people refer to it (mostly recruiters, luckily!). But then comes the question: what has changed besides the name? Our community friend Abhishek Gupta worked on this question and provided an excellent response titled "What's in a name? Java EE? J2EE?". But let me give you a few highlights here so you don't lose yourself with YATO (yet another tab opened): J2EE used to be an infrastructure and resources provider only, requiring developers to depend on external 3rd-party frameworks to then implement application requirements or improve productivity J2EE used to require hundreds of XML lines of codes to define just a dozen of resources like EJBs, MDBs, Servlets, and so on J2EE used to support only EAR (Enterprise Archives) with a bunch of other archives like JARs and WARs just to run a simple Web application And so on, and so on! It was a great technology but still required a lot of work to get something up and running. Remember xDoclet? Remember Struts? The old days of pure Hibernate code? Or when Ajax became a trending topic and we were all implementing it with DWR Servlet? Still, we J2EE developers survived, and learned, and helped evolve the platform to a whole new level of DX (Developer Experience). A new DX for J2EE suggested a new name. One that referred to the platform as the Enterprise Edition of Java, because "Java is why we're here" quoting Bill Shannon. The release of Java EE 5 included so many features that clearly showed developers the platform was going after all those DX gaps. Radical simplification of the persistence model with the introduction of JPA Support of Annotations following the launch of Java SE 5.0 Updated XML APIs with the introduction of StAX Drastic simplification of the EJB component model (with annotations!) Convention over Configuration and Dependency Injection A few bullets you may say but that represented a whole new DX and a vision for upcoming versions. Clearly, the release of Java EE 5 helped drive the future of the platform by reducing the number of XMLs, Java Interfaces, simplified configurations, provided convention-over-configuration, etc! We then saw the release of Java EE 6 with even more great features like Managed Beans, CDI, Bean Validation, improved JSP and Servlets APIs, JASPIC, the posisbility to deploy plain WARs and so many other improvements it is difficult to list in one sentence. And we've gotta give Spring Framework some credit here: thanks to Rod Johnson and team, concepts like Dependency Injection fit perfectly into the Java EE Platform. Clearly, Spring used to be one of the most inspiring frameworks for the Java EE platform, and it is great to see things like Pivotal and Spring supporting JSR 352 Batch API standard! Cooperation to keep improving DX at maximum in the server-side Java landscape.  The master piece result of these previous releases is seen and called today as Java EE 7, which by providing a newly and improved JavaServer Faces release, with new features for Web Development like WebSockets API, improved JAX-RS, and JSON-P, but also including Batch API and so many other great improvements, has increased developer productivity and brought innovation to server-side Java developers. Java EE is not just a new name (which was introduced back in May 2006!) but a new Developer Experience for server-side Java developers. To show you why we are here and where we are going (see the Java EE 8 update), we wanted to share with you a draft of the new Java EE logos that the evangelist team created, to help you spread the word about Java EE. You can get access to these images at the Java EE Platform Facebook Album, or the Google+ Java EE Platform Album whichever is better for you, but don't forget to like and/or +1 those social network profiles :-) A message to all job recruiters: stop using J2EE and start using Java EE if you want to find great Java EE 5, Java EE 6, or Java EE 7 developers To not only save you recruiter valuable characters when tweeting that job opportunity but to also match the correct term, we invite you to replace long terms like "Java/J2EE" or even worse "#Java #J2EE #JEE" or all these awkward combinations with the only acceptable hashtag: #JavaEE. And to prove that Java EE is catching among developers and even recruiters, and that J2EE is past, let me highlight here how are the jobs trends! The image below is from Indeed.com trends page, for the following keywords: J2EE, Java/J2EE, Java/JEE, JEE. As you can see, J2EE is indeed going away, while JEE saw some increase. Perhaps because some people are just lazy to type "Java" but at the same time they are aware that J2EE (the '2') is past. We shall forgive that for a while :-) Another proof that J2EE is going away is by looking at its trending statistics at Google. People have been showing less and less interest in the term J2EE. See the chart below:  Recruiter, if you still need proof that J2EE is past, that Java EE is trending, and that other job recruiters are seeking for Java EE developers, and that the developer community is aware of the new term, perhaps these other charts can show you what term you should be using. See for example the Job Trends for Java EE at Indeed.com and notice where it started... 2006! 8 years ago :-) Last but not least, the Google Trends for Java EE term (including the still wrong but forgivable JavaEE term) shows us that the new term is catching up very well. J2EE is past. Oh, and don't worry about the curves going down. We developers like to be hipsters sometimes and today only AngularJS, NodeJS, BigData are going up. Java EE and other traditional server-side technologies such as Spring, or even from other platforms such as Ruby on Rails, PHP, Grails, are pretty much consolidated and the curves... well, they are consolidated too. So If you are a Java EE developer, drop that J2EE from your résumé, and let recruiters also know that this term is past. Embrace Java EE, and enjoy a new developer experience for server-side Java developers. Java EE on TwitterJava EE on Google+Java EE on Facebook

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• SQL University: What and why of database testing

  - by Mladen Prajdic

  This is a post for a great idea called SQL University started by Jorge Segarra also famously known as SqlChicken on Twitter. It’s a collection of blog posts on different database related topics contributed by several smart people all over the world. So this week is mine and we’ll be talking about database testing and refactoring. In 3 posts we’ll cover: SQLU part 1 - What and why of database testing SQLU part 2 - What and why of database refactoring SQLU part 2 – Tools of the trade With that out of the way let us sharpen our pencils and get going. Why test a database The sad state of the industry today is that there is very little emphasis on testing in general. Test driven development is still a small niche of the programming world while refactoring is even smaller. The cause of this is the inability of developers to convince themselves and their managers that writing tests is beneficial. At the moment they are mostly viewed as waste of time. This is because the average person (let’s not fool ourselves, we’re all average) is unable to think about lower future costs in relation to little more current work. It’s orders of magnitude easier to know about the current costs in relation to current amount of work. That’s why programmers convince themselves testing is a waste of time. However we have to ask ourselves what tests are really about? Maybe finding bugs? No, not really. If we introduce bugs, we’re likely to write test around those bugs too. But yes we can find some bugs with tests. The main point of tests is to have reproducible repeatability in our systems. By having a code base largely covered by tests we can know with better certainty what a small code change can break in other parts of the system. By having repeatability we can make code changes with confidence, since we know we’ll see what breaks in other tests. And here comes the inability to estimate future costs. By spending just a few more hours writing those tests we’d know instantly what broke where. Imagine we fix a reported bug. We check-in the code, deploy it and the users are happy. Until we get a call 2 weeks later about a certain monthly process has stopped working. What we don’t know is that this process was developed by a long gone coworker and for some reason it relied on that same bug we’ve happily fixed. There’s no way we could’ve known that. We say OK and go in and fix the monthly process. But what we have no clue about is that there’s this ETL job that relied on data from that monthly process. Now that we’ve fixed the process it’s giving unexpected (yet correct since we fixed it) data to the ETL job. So we have to fix that too. But there’s this part of the app we coded that relies on data from that exact ETL job. And just like that we enter the “Loop of maintenance horror”. With the loop eventually comes blame. Here’s a nice tip for all developers and DBAs out there: If you make a mistake man up and admit to it. All of the above is valid for any kind of software development. Keeping this in mind the database is nothing other than just a part of the application. But a big part! One reason why testing a database is even more important than testing an application is that one database is usually accessed from multiple applications and processes. This makes it the central and vital part of the enterprise software infrastructure. Knowing all this can we really afford not to have tests? What to test in a database Now that we’ve decided we’ll dive into this testing thing we have to ask ourselves what needs to be tested? The short answer is: everything. The long answer is: read on! There are 2 main ways of doing tests: Black box and White box testing. Black box testing means we have no idea how the system internals are built and we only have access to it’s inputs and outputs. With it we test that the internal changes to the system haven’t caused the input/output behavior of the system to change. The most important thing to test here are the edge conditions. It’s where most programs break. Having good edge condition tests we can be more confident that the systems changes won’t break. White box testing has the full knowledge of the system internals. With it we test the internal system changes, different states of the application, etc… White and Black box tests should be complementary to each other as they are very much interconnected. Testing database routines includes testing stored procedures, views, user defined functions and anything you use to access the data with. Database routines are your input/output interface to the database system. They count as black box testing. We test then for 2 things: Data and schema. When testing schema we only care about the columns and the data types they’re returning. After all the schema is the contract to the out side systems. If it changes we usually have to change the applications accessing it. One helpful T-SQL command when doing schema tests is SET FMTONLY ON. It tells the SQL Server to return only empty results sets. This speeds up tests because it doesn’t return any data to the client. After we’ve validated the schema we have to test the returned data. There no other way to do this but to have expected data known before the tests executes and comparing that data to the database routine output. Testing Authentication and Authorization helps us validate who has access to the SQL Server box (Authentication) and who has access to certain database objects (Authorization). For desktop applications and windows authentication this works well. But the biggest problem here are web apps. They usually connect to the database as a single user. Please ensure that that user is not SA or an account with admin privileges. That is just bad. Load testing ensures us that our database can handle peak loads. One often overlooked tool for load testing is Microsoft’s OSTRESS tool. It’s part of RML utilities (x86, x64) for SQL Server and can help determine if our database server can handle loads like 100 simultaneous users each doing 10 requests per second. SQL Profiler can also help us here by looking at why certain queries are slow and what to do to fix them.   One particular problem to think about is how to begin testing existing databases. First thing we have to do is to get to know those databases. We can’t test something when we don’t know how it works. To do this we have to talk to the users of the applications accessing the database, run SQL Profiler to see what queries are being run, use existing documentation to decipher all the object relationships, etc… The way to approach this is to choose one part of the database (say a logical grouping of tables that go together) and filter our traces accordingly. Once we’ve done that we move on to the next grouping and so on until we’ve covered the whole database. Then we move on to the next one. Database Testing is a topic that we can spent many hours discussing but let this be a nice intro to the world of database testing. See you in the next post.

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• How do I get fan control working?

  - by RobinJ

  I know there something called fancontrol, that enables you to control the speed of your system's ventilation. I'd like to let my fans spin a bit faster as my laptop is heating up very easilly. All tutorials and stuff I've found are for old versions of Ubuntu and don't seem to be working anymore. Can anyone explain to me or give me a good link on how I can get it working on Ubuntu? Something different with the same effect is also fine.

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• Richmond Code Camp 2010.1 &ndash; Developing WPF Applications using Model-View-ViewModel

  - by John Blumenauer

  The code and slides from my Developing WPF Applications using Model-View-ViewModel session at Richmond Code Camp can be found HERE. During the session, a number of the attendees had some really great questions which tells me they’re really thinking about how to start using MVVM in their own apps.  I’ll be interested to hear feedback as they start investigating and introducing MVVM in their applications.  If you experience any problems downloading the slides or code, please let me know.

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• Physics/Graphics Components

  - by Brett Powell

  I have spent the last 48 hours reading up on Object Component systems, and feel I am ready enough to start implementing it. I got the base Object and Component classes created, but now that I need to start creating the actual components I am a bit confused. When I think of them in terms of HealthComponent or something that would basically just be a property, it makes perfect sense. When it is something more general as a Physics/Graphics component, I get a bit confused. My Object class looks like this so far (If you notice any changes I should make please let me know, still new to this)... typedef unsigned int ID; class GameObject { public: GameObject(ID id, Ogre::String name = ""); ~GameObject(); ID &getID(); Ogre::String &getName(); virtual void update() = 0; // Component Functions void addComponent(Component *component); void removeComponent(Ogre::String familyName); template<typename T> T* getComponent(Ogre::String familyName) { return dynamic_cast<T*>(m_components[familyName]); } protected: // Properties ID m_ID; Ogre::String m_Name; float m_flVelocity; Ogre::Vector3 m_vecPosition; // Components std::map<std::string,Component*> m_components; std::map<std::string,Component*>::iterator m_componentItr; }; Now the problem I am running into is what would the general population put into Components such as Physics/Graphics? For Ogre (my rendering engine) the visible Objects will consist of multiple Ogre::SceneNode (possibly multiple) to attach it to the scene, Ogre::Entity (possibly multiple) to show the visible meshes, and so on. Would it be best to just add multiple GraphicComponent's to the Object and let each GraphicComponent handle one SceneNode/Entity or is the idea to have one of each Component needed? For Physics I am even more confused. I suppose maybe creating a RigidBody and keeping track of mass/interia/etc. would make sense. But I am having trouble thinking of how to actually putting specifics into a Component. Once I get a couple of these "Required" components done, I think it will make a lot more sense. As of right now though I am still a bit stumped.

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• Upgrade Workshop in Warsaw today

  - by Mike Dietrich

  Thanks a lot - this was really impressive today. I don't know the exact number of attandees yet but it must have been more than 100 people. So I'd really like to thank you for this wonderful day in Warsaw. I've just made it to Budapest - and in case you are looking for the most recent version of the slides please download them from here: http://apex.oracle.com/folien and use the keyword (aka Schluesselwort): upgrade112 Thanks a lot - and let me know if your upgrades went fine :-)

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• Payment Gateway options other than Paypal, for sending out mass payments

  - by Rishav Rastogi

  We were using Paypal Payment pro earlier for the same thing, but for some reason Paypal has been given some new guideline which kinda hinder with the way we need to send out payments at the moment. We receive payments from clients and then send out payments back to vendors on a weekly basis ( deducting our cut ). Can you let me know what options are available to for such transactions other than paypal ? which is the best in terms cost of setup etc. Thanks

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