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  • Generating SQL for website

    - by Ethan
    I am working on a webapplication How can i create SQL for the following Database Information User information Username - String Password - String Admin or Client - boolean Last login – Date/Time LogItem typeLogItem – String (Page name?) hitCount – int View PageURL UserID Transaction User – String DateTimeStamp SKU – int Purchase-boolean TransactionID-int Inventory information Sku number - int Item description - String Price to customer - double Count - in

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  • Why should Java ThreadLocal variables be static

    - by kellyfj
    I was reading that JavaDoc for Threadlocal here http://java.sun.com/j2se/1.5.0/docs/api/java/lang/ThreadLocal.html and it says "ThreadLocal instances are typically private static fields in classes that wish to associate state with a thread (e.g., a user ID or Transaction ID). " But my question is why did they choose to make it static (typically) - it makes it a bit confusing to have "per thread" state but its static?

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  • GROUP BY and SUM distinct date across 2 tables

    - by kenitech
    I'm not sure if this is possible in one mysql query so I might just combine the results via php. I have 2 tables: 'users' and 'billing' I'm trying to group summed activity for every date that is available in these two tables. 'users' is not historical data but 'billing' contains a record for each transaction. In this example I am showing a user's status which I'd like to sum for created date and deposit amounts that I would also like to sum by created date. I realize there is a bit of a disconnect between the data but I'd like to some all of it together and display it as seen below. This will show me an overview of all of the users by when they were created and what the current statuses are next to total transactions. I've tried UNION as well as LEFT JOIN but I can't seem to get either to work. Union example is pretty close but doesn't combine the dates into one row. ( SELECT created, SUM(status) as totalActive, NULL as totalDeposit FROM users GROUP BY created ) UNION ( SELECT created, NULL as totalActive, SUM(transactionAmount) as totalDeposit FROM billing GROUP BY created ) I've also tried using a date lookup table and joining on the dates but the SUM values are being added multiple times. note: I don't care about the userIds at all but have it in here for the example. users table (where status of '1' denotes "active") (one record for each user) created | userId | status 2010-03-01 | 10 | 0 2010-03-01 | 11 | 1 2010-03-01 | 12 | 1 2010-03-10 | 13 | 0 2010-03-12 | 14 | 1 2010-03-12 | 15 | 1 2010-03-13 | 16 | 0 2010-03-15 | 17 | 1 billing table (record created for every instance of a billing "transaction" created | userId | transactionAmount 2010-03-01 | 10 | 50 2010-03-01 | 18 | 50 2010-03-01 | 19 | 100 2010-03-10 | 89 | 55 2010-03-15 | 16 | 50 2010-03-15 | 12 | 90 2010-03-22 | 99 | 150 desired result: created | sumStatusActive | sumStatusInactive | sumTransactions 2010-03-01 | 2 | 1 | 200 2010-03-10 | 0 | 1 | 55 2010-03-12 | 2 | 0 | 0 2010-03-13 | 0 | 0 | 0 2010-03-15 | 1 | 0 | 140 2010-03-22 | 0 | 0 | 150 Table dump: CREATE TABLE IF NOT EXISTS `users` ( `created` date NOT NULL, `userId` int(11) NOT NULL, `status` smallint(6) NOT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1; INSERT INTO `users` (`created`, `userId`, `status`) VALUES ('2010-03-01', 10, 0), ('2010-03-01', 11, 1), ('2010-03-01', 12, 1), ('2010-03-10', 13, 0), ('2010-03-12', 14, 1), ('2010-03-12', 15, 1), ('2010-03-13', 16, 0), ('2010-03-15', 17, 1); CREATE TABLE IF NOT EXISTS `billing` ( `created` date NOT NULL, `userId` int(11) NOT NULL, `transactionAmount` int(11) NOT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1; INSERT INTO `billing` (`created`, `userId`, `transactionAmount`) VALUES ('2010-03-01', 10, 50), ('2010-03-01', 18, 50), ('2010-03-01', 19, 100), ('2010-03-10', 89, 55), ('2010-03-15', 16, 50), ('2010-03-15', 12, 90), ('2010-03-22', 99, 150);

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  • SQL - when should you use "with (nolock)"

    - by Andy White
    Can someone explain the implications of using "with (nolock)" on queries, when you should/shouldn't use it? For example, if you have a banking application with high transaction rates and a lot of data in certain tables, in what types of queries would nolock be okay? Are there cases when you should always use it/never use it?

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  • MySQL Data Truncation: Out of range value in Performance test

    - by Khaledez
    on a test for Java-MySQL-Restlet application, I write to database at 4reqs/second for 120 seconds. In this write I insert a row that has foreign key which has the same value for all rows, and this exception occurs: Could not recover transaction. Original exception follows. com.mysql.jdbc.MysqlDataTruncation: Data truncation: Out of range value for column 'idPxxx' at row 1 Only 5% of requests fails to this exceptions, others works. Regards

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  • "Blank SQL" error with phppgadmin

    - by Hoàng Long
    Here is my problem: I export a database A_DB using "export" function of Phppgadmin. The dump file A_dump.sql includes both the database structure and data. Then I try to create another blank database B_DB, and import A_dump.sql into it. Every time I do that, the transaction failed with no error reported: SQL error: In statement: Is there some logs that I can find in phppgadmin that would allow me to investigate this problem? I have tried searching for an hour, but still not find anything.

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  • Reuse Hibernate session in thread

    - by Marco
    Hello, I've read somewhere that when a session is flushed or a transaction is committed, the session itself is closed by Hibernate. So, how can i reuse an Hibernate Session, in the same thread, that has been previously closed? Thanks

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  • What's the quickest way to dump & load a MySQL InnoDB database using mysqldump?

    - by Josh Schwartzman
    I would like to create a copy of a database with approximately 40 InnoDB tables and around 1.5GB of data with mysqldump and MySQL 5.1. What are the best parameters (ie: --single-transaction) that will result in the quickest dump and load of the data? As well, when loading the data into the second DB, is it quicker to: 1) pipe the results directly to the second MySQL server instance and use the --compress option or 2) load it from a text file (ie: mysql < my_sql_dump.sql)

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  • How to get the sql query from a NHibernate save

    - by adriaanp
    I am trying to create a type of recorded data transaction that I can replay on a different database. For example I am capturing an order into a system, when I save that I want to be able to "export" a sql script that I can run on another database to create the same order. I am using NHibernate and I am trying to catch the sql query string for the save operation to save to a file, but with no success.

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  • Handling large numbers of sockets with .NET

    - by Dreaddan
    I'm looking at writing a application that need to be able to handle in the region of 200 connections / sec and was wondering if C# and .NET will handle this or if I need to really be looking at C++ to do this? It looks like SocketAsyncEventArgs may be the way to go but thought id check before I plough in to it. Each transaction should only last less than a second but could take up to 15 seconds each if that makes any difference.

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  • How to calculate paypal fees, 2.9% +0.30 doesn't work for some cases variable FEEAMT in checkout met

    - by dev-cu
    Hello to everyone, thanks for reading this. I am implementing paypal checkout in my website it is working but i want to make a simple fees calculator for paypal in order to help the user, i went to paypal and they said their fees amount is 2.9% +0.30 fixed, but it is not working for some cases, for example: deposit $1.34 2.9 % = $0.04 rounded + $0.30 = $0.34, so i should get $1 credited but paypal send in its response in the field FEEAMT which indicate the "PayPal fee amount charged for the transaction" 0.35, what i am doing wrong? Thanks in advance.

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  • SSIS - Access Denied with UNC paths - The file name is a device or contains invalid characters

    - by simonsabin
    I spent another day tearing my hair out yesterday trying to resolve an issue with SSIS packages runnning in SQLAgent (not got much left at the moment, maybe I should contact the SSIS team for a wig). My situation was that I am deploying packages to a development server, and to provide isolation I was running jobs with a proxy account that only had access to the development servers. Proxies are an awesome feature and mean that you should never have to "just run the job as sysadmin". The issue I was facing was that the job step was failing. The job step was a simple execution of the package.The following errors appeared in my log file. I always check the "Log step output in history" for a job step, this ensures you get all the output from the command that you run. I'll blog about this later. If looking at the output in sysdtslog90 then you will have an entry with datacode -1073573533 and error message File or directory "<filename>" represented by connection "<connection>" does not exist.  Not exactly helpful. If you get the output from the console then you will also get these errors. 0xC0202070 "The file name property is not valid. The file name is a device or contains invalid characters." 0xC001401E "specified in the connection was not valid." It appears this error is due to the use of a UNC path and the account runnnig the package not having access to all the folders in the path. Solution To solve this you need to ensure that the proxy account has access to ALL folders in the path you are accessing. To check this works, logon as the relevant proxy user, or run a command window as the specified user. Then try and do net use \\server\share and then do a dir for each folder in the path and check you have access. If these work and you still have the problem then you have some other problem, sorry. The following are posts on experts exchange that also discuss this,http://www.experts-exchange.com/Microsoft/Development/MS-SQL-Server/SSIS/Q_24056047.htmlhttp://www.experts-exchange.com/Microsoft/Development/MS-SQL-Server/SSIS/Q_23968903.html This blog had a post about it being a 64 bit issue. That definitely wasn't the issue for me as I was on a 32 bit server http://blogs.perkinsconsulting.com/post/64-bit-SQL-Server-2005-SSIS-and-UNC-paths-Part-2.aspx  

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  • Guidance: A Branching strategy for Scrum Teams

    - by Martin Hinshelwood
    Having a good branching strategy will save your bacon, or at least your code. Be careful when deviating from your branching strategy because if you do, you may be worse off than when you started! This is one possible branching strategy for Scrum teams and I will not be going in depth with Scrum but you can find out more about Scrum by reading the Scrum Guide and you can even assess your Scrum knowledge by having a go at the Scrum Open Assessment. You can also read SSW’s Rules to Better Scrum using TFS which have been developed during our own Scrum implementations. Acknowledgements Bill Heys – Bill offered some good feedback on this post and helped soften the language. Note: Bill is a VS ALM Ranger and co-wrote the Branching Guidance for TFS 2010 Willy-Peter Schaub – Willy-Peter is an ex Visual Studio ALM MVP turned blue badge and has been involved in most of the guidance including the Branching Guidance for TFS 2010 Chris Birmele – Chris wrote some of the early TFS Branching and Merging Guidance. Dr Paul Neumeyer, Ph.D Parallel Processes, ScrumMaster and SSW Solution Architect – Paul wanted to have feature branches coming from the release branch as well. We agreed that this is really a spin-off that needs own project, backlog, budget and Team. Scenario: A product is developed RTM 1.0 is released and gets great sales.  Extra features are demanded but the new version will have double to price to pay to recover costs, work is approved by the guys with budget and a few sprints later RTM 2.0 is released.  Sales a very low due to the pricing strategy. There are lots of clients on RTM 1.0 calling out for patches. As I keep getting Reverse Integration and Forward Integration mixed up and Bill keeps slapping my wrists I thought I should have a reminder: You still seemed to use reverse and/or forward integration in the wrong context. I would recommend reviewing your document at the end to ensure that it agrees with the common understanding of these terms merge (forward integration) from parent to child (same direction as the branch), and merge  (reverse integration) from child to parent (the reverse direction of the branch). - one of my many slaps on the wrist from Bill Heys.   As I mentioned previously we are using a single feature branching strategy in our current project. The single biggest mistake developers make is developing against the “Main” or “Trunk” line. This ultimately leads to messy code as things are added and never finished. Your only alternative is to NEVER check in unless your code is 100%, but this does not work in practice, even with a single developer. Your ADD will kick in and your half-finished code will be finished enough to pass the build and the tests. You do use builds don’t you? Sadly, this is a very common scenario and I have had people argue that branching merely adds complexity. Then again I have seen the other side of the universe ... branching  structures from he... We should somehow convince everyone that there is a happy between no-branching and too-much-branching. - Willy-Peter Schaub, VS ALM Ranger, Microsoft   A key benefit of branching for development is to isolate changes from the stable Main branch. Branching adds sanity more than it adds complexity. We do try to stress in our guidance that it is important to justify a branch, by doing a cost benefit analysis. The primary cost is the effort to do merges and resolve conflicts. A key benefit is that you have a stable code base in Main and accept changes into Main only after they pass quality gates, etc. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft The second biggest mistake developers make is branching anything other than the WHOLE “Main” line. If you branch parts of your code and not others it gets out of sync and can make integration a nightmare. You should have your Source, Assets, Build scripts deployment scripts and dependencies inside the “Main” folder and branch the whole thing. Some departments within MSFT even go as far as to add the environments used to develop the product in there as well; although I would not recommend that unless you have a massive SQL cluster to house your source code. We tried the “add environment” back in South-Africa and while it was “phenomenal”, especially when having to switch between environments, the disk storage and processing requirements killed us. We opted for virtualization to skin this cat of keeping a ready-to-go environment handy. - Willy-Peter Schaub, VS ALM Ranger, Microsoft   I think people often think that you should have separate branches for separate environments (e.g. Dev, Test, Integration Test, QA, etc.). I prefer to think of deploying to environments (such as from Main to QA) rather than branching for QA). - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   You can read about SSW’s Rules to better Source Control for some additional information on what Source Control to use and how to use it. There are also a number of branching Anti-Patterns that should be avoided at all costs: You know you are on the wrong track if you experience one or more of the following symptoms in your development environment: Merge Paranoia—avoiding merging at all cost, usually because of a fear of the consequences. Merge Mania—spending too much time merging software assets instead of developing them. Big Bang Merge—deferring branch merging to the end of the development effort and attempting to merge all branches simultaneously. Never-Ending Merge—continuous merging activity because there is always more to merge. Wrong-Way Merge—merging a software asset version with an earlier version. Branch Mania—creating many branches for no apparent reason. Cascading Branches—branching but never merging back to the main line. Mysterious Branches—branching for no apparent reason. Temporary Branches—branching for changing reasons, so the branch becomes a permanent temporary workspace. Volatile Branches—branching with unstable software assets shared by other branches or merged into another branch. Note   Branches are volatile most of the time while they exist as independent branches. That is the point of having them. The difference is that you should not share or merge branches while they are in an unstable state. Development Freeze—stopping all development activities while branching, merging, and building new base lines. Berlin Wall—using branches to divide the development team members, instead of dividing the work they are performing. -Branching and Merging Primer by Chris Birmele - Developer Tools Technical Specialist at Microsoft Pty Ltd in Australia   In fact, this can result in a merge exercise no-one wants to be involved in, merging hundreds of thousands of change sets and trying to get a consolidated build. Again, we need to find a happy medium. - Willy-Peter Schaub on Merge Paranoia Merge conflicts are generally the result of making changes to the same file in both the target and source branch. If you create merge conflicts, you will eventually need to resolve them. Often the resolution is manual. Merging more frequently allows you to resolve these conflicts close to when they happen, making the resolution clearer. Waiting weeks or months to resolve them, the Big Bang approach, means you are more likely to resolve conflicts incorrectly. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   Figure: Main line, this is where your stable code lives and where any build has known entities, always passes and has a happy test that passes as well? Many development projects consist of, a single “Main” line of source and artifacts. This is good; at least there is source control . There are however a couple of issues that need to be considered. What happens if: you and your team are working on a new set of features and the customer wants a change to his current version? you are working on two features and the customer decides to abandon one of them? you have two teams working on different feature sets and their changes start interfering with each other? I just use labels instead of branches? That's a lot of “what if’s”, but there is a simple way of preventing this. Branching… In TFS, labels are not immutable. This does not mean they are not useful. But labels do not provide a very good development isolation mechanism. Branching allows separate code sets to evolve separately (e.g. Current with hotfixes, and vNext with new development). I don’t see how labels work here. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   Figure: Creating a single feature branch means you can isolate the development work on that branch.   Its standard practice for large projects with lots of developers to use Feature branching and you can check the Branching Guidance for the latest recommendations from the Visual Studio ALM Rangers for other methods. In the diagram above you can see my recommendation for branching when using Scrum development with TFS 2010. It consists of a single Sprint branch to contain all the changes for the current sprint. The main branch has the permissions changes so contributors to the project can only Branch and Merge with “Main”. This will prevent accidental check-ins or checkouts of the “Main” line that would contaminate the code. The developers continue to develop on sprint one until the completion of the sprint. Note: In the real world, starting a new Greenfield project, this process starts at Sprint 2 as at the start of Sprint 1 you would have artifacts in version control and no need for isolation.   Figure: Once the sprint is complete the Sprint 1 code can then be merged back into the Main line. There are always good practices to follow, and one is to always do a Forward Integration from Main into Sprint 1 before you do a Reverse Integration from Sprint 1 back into Main. In this case it may seem superfluous, but this builds good muscle memory into your developer’s work ethic and means that no bad habits are learned that would interfere with additional Scrum Teams being added to the Product. The process of completing your sprint development: The Team completes their work according to their definition of done. Merge from “Main” into “Sprint1” (Forward Integration) Stabilize your code with any changes coming from other Scrum Teams working on the same product. If you have one Scrum Team this should be quick, but there may have been bug fixes in the Release branches. (we will talk about release branches later) Merge from “Sprint1” into “Main” to commit your changes. (Reverse Integration) Check-in Delete the Sprint1 branch Note: The Sprint 1 branch is no longer required as its useful life has been concluded. Check-in Done But you are not yet done with the Sprint. The goal in Scrum is to have a “potentially shippable product” at the end of every Sprint, and we do not have that yet, we only have finished code.   Figure: With Sprint 1 merged you can create a Release branch and run your final packaging and testing In 99% of all projects I have been involved in or watched, a “shippable product” only happens towards the end of the overall lifecycle, especially when sprints are short. The in-between releases are great demonstration releases, but not shippable. Perhaps it comes from my 80’s brain washing that we only ship when we reach the agreed quality and business feature bar. - Willy-Peter Schaub, VS ALM Ranger, Microsoft Although you should have been testing and packaging your code all the way through your Sprint 1 development, preferably using an automated process, you still need to test and package with stable unchanging code. This is where you do what at SSW we call a “Test Please”. This is first an internal test of the product to make sure it meets the needs of the customer and you generally use a resource external to your Team. Then a “Test Please” is conducted with the Product Owner to make sure he is happy with the output. You can read about how to conduct a Test Please on our Rules to Successful Projects: Do you conduct an internal "test please" prior to releasing a version to a client?   Figure: If you find a deviation from the expected result you fix it on the Release branch. If during your final testing or your “Test Please” you find there are issues or bugs then you should fix them on the release branch. If you can’t fix them within the time box of your Sprint, then you will need to create a Bug and put it onto the backlog for prioritization by the Product owner. Make sure you leave plenty of time between your merge from the development branch to find and fix any problems that are uncovered. This process is commonly called Stabilization and should always be conducted once you have completed all of your User Stories and integrated all of your branches. Even once you have stabilized and released, you should not delete the release branch as you would with the Sprint branch. It has a usefulness for servicing that may extend well beyond the limited life you expect of it. Note: Don't get forced by the business into adding features into a Release branch instead that indicates the unspoken requirement is that they are asking for a product spin-off. In this case you can create a new Team Project and branch from the required Release branch to create a new Main branch for that product. And you create a whole new backlog to work from.   Figure: When the Team decides it is happy with the product you can create a RTM branch. Once you have fixed all the bugs you can, and added any you can’t to the Product Backlog, and you Team is happy with the result you can create a Release. This would consist of doing the final Build and Packaging it up ready for your Sprint Review meeting. You would then create a read-only branch that represents the code you “shipped”. This is really an Audit trail branch that is optional, but is good practice. You could use a Label, but Labels are not Auditable and if a dispute was raised by the customer you can produce a verifiable version of the source code for an independent party to check. Rare I know, but you do not want to be at the wrong end of a legal battle. Like the Release branch the RTM branch should never be deleted, or only deleted according to your companies legal policy, which in the UK is usually 7 years.   Figure: If you have made any changes in the Release you will need to merge back up to Main in order to finalise the changes. Nothing is really ever done until it is in Main. The same rules apply when merging any fixes in the Release branch back into Main and you should do a reverse merge before a forward merge, again for the muscle memory more than necessity at this stage. Your Sprint is now nearly complete, and you can have a Sprint Review meeting knowing that you have made every effort and taken every precaution to protect your customer’s investment. Note: In order to really achieve protection for both you and your client you would add Automated Builds, Automated Tests, Automated Acceptance tests, Acceptance test tracking, Unit Tests, Load tests, Web test and all the other good engineering practices that help produce reliable software.     Figure: After the Sprint Planning meeting the process begins again. Where the Sprint Review and Retrospective meetings mark the end of the Sprint, the Sprint Planning meeting marks the beginning. After you have completed your Sprint Planning and you know what you are trying to achieve in Sprint 2 you can create your new Branch to develop in. How do we handle a bug(s) in production that can’t wait? Although in Scrum the only work done should be on the backlog there should be a little buffer added to the Sprint Planning for contingencies. One of these contingencies is a bug in the current release that can’t wait for the Sprint to finish. But how do you handle that? Willy-Peter Schaub asked an excellent question on the release activities: In reality Sprint 2 starts when sprint 1 ends + weekend. Should we not cater for a possible parallelism between Sprint 2 and the release activities of sprint 1? It would introduce FI’s from main to sprint 2, I guess. Your “Figure: Merging print 2 back into Main.” covers, what I tend to believe to be reality in most cases. - Willy-Peter Schaub, VS ALM Ranger, Microsoft I agree, and if you have a single Scrum team then your resources are limited. The Scrum Team is responsible for packaging and release, so at least one run at stabilization, package and release should be included in the Sprint time box. If more are needed on the current production release during the Sprint 2 time box then resource needs to be pulled from Sprint 2. The Product Owner and the Team have four choices (in order of disruption/cost): Backlog: Add the bug to the backlog and fix it in the next Sprint Buffer Time: Use any buffer time included in the current Sprint to fix the bug quickly Make time: Remove a Story from the current Sprint that is of equal value to the time lost fixing the bug(s) and releasing. Note: The Team must agree that it can still meet the Sprint Goal. Cancel Sprint: Cancel the sprint and concentrate all resource on fixing the bug(s) Note: This can be a very costly if the current sprint has already had a lot of work completed as it will be lost. The choice will depend on the complexity and severity of the bug(s) and both the Product Owner and the Team need to agree. In this case we will go with option #2 or #3 as they are uncomplicated but severe bugs. Figure: Real world issue where a bug needs fixed in the current release. If the bug(s) is urgent enough then then your only option is to fix it in place. You can edit the release branch to find and fix the bug, hopefully creating a test so it can’t happen again. Follow the prior process and conduct an internal and customer “Test Please” before releasing. You can read about how to conduct a Test Please on our Rules to Successful Projects: Do you conduct an internal "test please" prior to releasing a version to a client?   Figure: After you have fixed the bug you need to ship again. You then need to again create an RTM branch to hold the version of the code you released in escrow.   Figure: Main is now out of sync with your Release. We now need to get these new changes back up into the Main branch. Do a reverse and then forward merge again to get the new code into Main. But what about the branch, are developers not working on Sprint 2? Does Sprint 2 now have changes that are not in Main and Main now have changes that are not in Sprint 2? Well, yes… and this is part of the hit you take doing branching. But would this scenario even have been possible without branching?   Figure: Getting the changes in Main into Sprint 2 is very important. The Team now needs to do a Forward Integration merge into their Sprint and resolve any conflicts that occur. Maybe the bug has already been fixed in Sprint 2, maybe the bug no longer exists! This needs to be identified and resolved by the developers before they continue to get further out of Sync with Main. Note: Avoid the “Big bang merge” at all costs.   Figure: Merging Sprint 2 back into Main, the Forward Integration, and R0 terminates. Sprint 2 now merges (Reverse Integration) back into Main following the procedures we have already established.   Figure: The logical conclusion. This then allows the creation of the next release. By now you should be getting the big picture and hopefully you learned something useful from this post. I know I have enjoyed writing it as I find these exploratory posts coupled with real world experience really help harden my understanding.  Branching is a tool; it is not a silver bullet. Don’t over use it, and avoid “Anti-Patterns” where possible. Although the diagram above looks complicated I hope showing you how it is formed simplifies it as much as possible.   Technorati Tags: Branching,Scrum,VS ALM,TFS 2010,VS2010

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  • SQLAuthority News – Monthly Roundup of Best SQL Posts

    - by pinaldave
    After receiving lots of requests from different readers for long time I have decided to write first monthly round up. If all of you like it I will continue writing the same every month. In fact, I really like the idea as I was able to go back and read all of my posts written in this month. This month was started with answering one of the most common question asked me to about What is Adventureworks? Many of you know the answer but to the surprise more number of the reader did not know the answer. There were few extra blog post which were in the same line as following. SQL SERVER – The Difference between Dual Core vs. Core 2 Duo SQLAuthority News – Wireless Router Security and Attached Devices – Complex Password SQL SERVER – DATE and TIME in SQL Server 2008 DMVs are also one of the most handy tools available in SQL Server, I have written following blog post where I have used DMV in scripts. SQL SERVER – Get Latest SQL Query for Sessions – DMV SQL SERVER – Find Most Expensive Queries Using DMV SQL SERVER – List All the DMV and DMF on Server I was able to write two follow-up of my earlier series where I was finding the size of the indexes using different SQL Scripts. And in fact one of the article Powershell is used as well. This was my very first attempt to use Powershell. SQL SERVER – Size of Index Table for Each Index – Solution 2 SQL SERVER – Size of Index Table for Each Index – Solution 3 – Powershell SQL SERVER – Four Posts on Removing the Bookmark Lookup – Key Lookup Without realizing I wrote series of the blog post on disabled index here is its complete list. I plan to write one more follow-up list on the same. SQL SERVER – Disable Clustered Index and Data Insert SQL SERVER – Understanding ALTER INDEX ALL REBUILD with Disabled Clustered Index SQL SERVER – Disabled Index and Update Statistics Two special post which I found very interesting to write are as following. SQL SERVER – SHRINKFILE and TRUNCATE Log File in SQL Server 2008 SQL SERVER – Simple Example of Snapshot Isolation – Reduce the Blocking Transactions In personal adventures, I won the Community Impact Award for Last Year from Microsoft. Please leave your comment about how can I improve this round up or what more details I should include in the same. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

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  • Why should you choose Oracle WebLogic 12c instead of JBoss EAP 6?

    - by Ricardo Ferreira
    In this post, I will cover some technical differences between Oracle WebLogic 12c and JBoss EAP 6, which was released a couple days ago from Red Hat. This article claims to help you in the evaluation of key points that you should consider when choosing for an Java EE application server. In the following sections, I will present to you some important aspects that most customers ask us when they are seriously evaluating for an middleware infrastructure, specially if you are considering JBoss for some reason. I would suggest that you keep the following question in mind while you are reading the points: "Why should I choose JBoss instead of WebLogic?" 1) Multi Datacenter Deployment and Clustering - D/R ("Disaster & Recovery") architecture support is embedded on the WebLogic Server 12c product. JBoss EAP 6 on the other hand has no direct D/R support included, Red Hat relies on third-part tools with higher prices. When you consider a middleware solution to host your business critical application, you should worry with every architectural aspect that are related with the solution. Fail-over support is one little aspect of a truly reliable solution. If you do not worry about D/R, your solution will not be reliable. Having said that, with Red Hat and JBoss EAP 6, you have this extra cost that will increase considerably the total cost of ownership of the solution. As we commonly hear from analysts, open-source are not so cheaper when you start seeing the big picture. - WebLogic Server 12c supports advanced LAN clustering, detection of death servers and have a common alert framework. JBoss EAP 6 on the other hand has limited LAN clustering support with no server death detection. They do not generate any alerts when servers goes down (only if you buy JBoss ON which is a separated technology, but until now does not support JBoss EAP 6) and manual intervention are required when servers goes down. In most cases, admin people must rely on "kill -9", "tail -f someFile.log" and "ps ax | grep java" commands to manage failures and clustering anomalies. - WebLogic Server 12c supports the concept of Node Manager, which is a separated process that runs on the physical | virtual servers that allows extend the administration of the cluster to WebLogic managed servers that are often distributed across multiple machines and geographic locations. JBoss EAP 6 on the other hand has no equivalent technology. Whole server instances must be managed individually. - WebLogic Server 12c Node Manager supports Coherence to boost performance when managing servers. JBoss EAP 6 on the other hand has no similar technology. There is no way to coordinate JBoss and infiniband instances provided by JBoss using high throughput and low latency protocols like InfiniBand. The Node Manager feature also allows another very important feature that JBoss EAP lacks: secure the administration. When using WebLogic Node Manager, all the administration tasks are sent to the managed servers in a secure tunel protected by a certificate, which means that the transport layer that separates the WebLogic administration console from the managed servers are secured by SSL. - WebLogic Server 12c are now integrated with OTD ("Oracle Traffic Director") which is a web server technology derived from the former Sun iPlanet Web Server. This software complements the web server support offered by OHS ("Oracle HTTP Server"). Using OTD, WebLogic instances are load-balanced by a high powerful software that knows how to handle SDP ("Socket Direct Protocol") over InfiniBand, which boost performance when used with engineered systems technologies like Oracle Exalogic Elastic Cloud. JBoss EAP 6 on the other hand only offers support to Apache Web Server with custom modules created to deal with JBoss clusters, but only across standard TCP/IP networks.  2) Application and Runtime Diagnostics - WebLogic Server 12c have diagnostics capabilities embedded on the server called WLDF ("WebLogic Diagnostic Framework") so there is no need to rely on third-part tools. JBoss EAP 6 on the other hand has no diagnostics capabilities. Their only diagnostics tool is the log generated by the application server. Admin people are encouraged to analyse thousands of log lines to find out what is going on. - WebLogic Server 12c complement WLDF with JRockit MC ("Mission Control"), which provides to administrators and developers a complete insight about the JVM performance, behavior and possible bottlenecks. WebLogic Server 12c also have an classloader analysis tool embedded, and even a log analyzer tool that enables administrators and developers to view logs of multiple servers at the same time. JBoss EAP 6 on the other hand relies on third-part tools to do something similar. Again, only log searching are offered to find out whats going on. - WebLogic Server 12c offers end-to-end traceability and monitoring available through Oracle EM ("Enterprise Manager"), including monitoring of business transactions that flows through web servers, ESBs, application servers and database servers, all of this with high deep JVM analysis and diagnostics. JBoss EAP 6 on the other hand, even using JBoss ON ("Operations Network"), which is a separated technology, does not support those features. Red Hat relies on third-part tools to provide direct Oracle database traceability across JVMs. One of those tools are Oracle EM for non-Oracle middleware that manage JBoss, Tomcat, Websphere and IIS transparently. - WebLogic Server 12c with their JRockit support offers a tool called JRockit Flight Recorder, which can give developers a complete visibility of a certain period of application production monitoring with zero extra overhead. This automatic recording allows you to deep analyse threads latency, memory leaks, thread contention, resource utilization, stack overflow damages and GC ("Garbage Collection") cycles, to observe in real time stop-the-world phenomenons, generational, reference count and parallel collects and mutator threads analysis. JBoss EAP 6 don't even dream to support something similar, even because they don't have their own JVM. 3) Application Server Administration - WebLogic Server 12c offers a complete administration console complemented with scripting and macro-like recording capabilities. A single WebLogic console can managed up to hundreds of WebLogic servers belonging to the same domain. JBoss EAP 6 on the other hand has a limited console and provides a XML centric administration. JBoss, after ten years, started the development of a rudimentary centralized administration that still leave a lot of administration tasks aside, so admin people and developers must touch scripts and XML configuration files for most advanced and even simple administration tasks. This lead applications to error prone and risky deployments. Even using JBoss ON, JBoss EAP are not able to offer decent administration features for admin people which must be high skilled in JBoss internal architecture and its managing capabilities. - Oracle EM is available to manage multiple domains, databases, application servers, operating systems and virtualization, with a complete end-to-end visibility. JBoss ON does not provide management capabilities across the complete architecture, only basic monitoring. Even deployment must be done aside JBoss ON which does no integrate well with others softwares than JBoss. Until now, JBoss ON does not supports JBoss EAP 6, so even their minimal support for JBoss are not available for JBoss EAP 6 leaving customers uncovered and subject to high skilled JBoss admin people. - WebLogic Server 12c has the same administration model whatever is the topology selected by the customer. JBoss EAP 6 on the other hand differentiates between two operational models: standalone-mode and domain-mode, that are not consistent with each other. Depending on the mode used, the administration skill is different. - WebLogic Server 12c has no point-of-failures processes, and it does not need to define any specialized server. Domain model in WebLogic is available for years (at least ten years or more) and is production proven. JBoss EAP 6 on the other hand needs special processes to garantee JBoss integrity, the PC ("Process-Controller") and the HC ("Host-Controller"). Different from WebLogic, the domain model in JBoss is quite new (one year at tops) of maturity, and need to mature considerably until start doing things like WebLogic domain model does. - WebLogic Server 12c supports parallel deployment model which enables some artifacts being deployed at the same time. JBoss EAP 6 on the other hand does not have any similar feature. Every deployment are done atomically in the containers. This means that if you have a huge EAR (an EAR of 120 MB of size for instance) and deploy onto JBoss EAP 6, this EAR will take some minutes in order to starting accept thread requests. The same EAR deployed onto WebLogic Server 12c will reduce the deployment time at least in 2X compared to JBoss. 4) Support and Upgrades - WebLogic Server 12c has patch management available. JBoss EAP 6 on the other hand has no patch management available, each JBoss EAP instance should be patched manually. To achieve such feature, you need to buy a separated technology called JBoss ON ("Operations Network") that manage this type of stuff. But until now, JBoss ON does not support JBoss EAP 6 so, in practice, JBoss EAP 6 does not have this feature. - WebLogic Server 12c supports previuous WebLogic domains without any reconfiguration since its kernel is robust and mature since its creation in 1995. JBoss EAP 6 on the other hand has a proven lack of supportability between JBoss AS 4, 5, 6 and 7. Different kernels and messaging engines were implemented in JBoss stack in the last five years reveling their incapacity to create a well architected and proven middleware technology. - WebLogic Server 12c has patch prescription based on customer configuration. JBoss EAP 6 on the other hand has no such capability. People need to create ticket supports and have their installations revised by Red Hat support guys to gain some patch prescription from them. - Oracle WebLogic Server independent of the version has 8 years of support of new patches and has lifetime release of existing patches beyond that. JBoss EAP 6 on the other hand provides patches for a specific application server version up to 5 years after the release date. JBoss EAP 4 and previous versions had only 4 years. A good question that Red Hat will argue to answer is: "what happens when you find issues after year 5"?  5) RAC ("Real Application Clusters") Support - WebLogic Server 12c ships with a specific JDBC driver to leverage Oracle RAC clustering capabilities (Fast-Application-Notification, Transaction Affinity, Fast-Connection-Failover, etc). Oracle JDBC thin driver are also available. JBoss EAP 6 on the other hand ships only the standard Oracle JDBC thin driver. Load balancing with Oracle RAC are not supported. Manual intervention in case of planned or unplanned RAC downtime are necessary. In JBoss EAP 6, situation does not reestablish automatically after downtime. - WebLogic Server 12c has a feature called Active GridLink for Oracle RAC which provides up to 3X performance on OLTP applications. This seamless integration between WebLogic and Oracle database enable more value added to critical business applications leveraging their investments in Oracle database technology and Oracle middleware. JBoss EAP 6 on the other hand has no performance gains at all, even when admin people implement some kind of connection-pooling tuning. - WebLogic Server 12c also supports transaction and web session affinity to the Oracle RAC, which provides aditional gains of performance. This is particularly interesting if you are creating a reliable solution that are distributed not only in an LAN cluster, but into a different data center. JBoss EAP 6 on the other hand has no such support. 6) Standards and Technology Support - WebLogic Server 12c is fully Java EE 6 compatible and production ready since december of 2011. JBoss EAP 6 on the other hand became fully compatible with Java EE 6 only in the community version after three months, and production ready only in a few days considering that this article was written in June of 2012. Red Hat says that they are the masters of innovation and technology proliferation, but compared with Oracle and even other proprietary vendors like IBM, they historically speaking are lazy to deliver the most newest technologies and standards adherence. - Oracle is the steward of Java, driving innovation into the platform from commercial and open-source vendors. Red Hat on the other hand does not have its own JVM and relies on third-part JVMs to complete their application server offer. 95% of Red Hat customers are using Oracle HotSpot as JVM, which means that without Oracle involvement, their support are limited exclusively to the application server layer and we all know that most problems are happens in the JVM layer. - WebLogic Server 12c supports natively JDK 7, which empower developers to explore the maximum of the Java platform productivity when writing code. This feature differentiate WebLogic from others application servers (except GlassFish that are also managed by Oracle) because the usage of JDK 7 introduce such remarkable productivity features like the "try-with-resources" enhancement, catching multiple exceptions with one try block, Strings in the switch statements, JVM improvements in terms of JDBC, I/O, networking, security, concurrency and of course, the most important feature of Java 7: native support for multiple non-Java languages. More features regarding JDK 7 can be found here. JBoss EAP 6 on the other hand does not support JDK 7 officially, they comment in their community version that "Java SE 7 can be used with JBoss 7" which does not gives you any guarantees of enterprise support for JDK 7. - Oracle WebLogic Server 12c supports integration with Spring framework allowing Spring applications to use WebLogic special transaction manager, exposing bean interfaces to WebLogic MBeans to take advantage of all WebLogic monitoring and administration advantages. JBoss EAP 6 on the other hand has no special integration with Spring. In fact, Red Hat offers a suspicious package called "JBoss Web Platform" that in theory supports Spring, but in practice this package does not offers any special integration. It is just a facility for Red Hat customers to have support from both JBoss and Spring technology using the same customer support. 7) Lightweight Development - Oracle WebLogic Server 12c and Oracle GlassFish are completely integrated and can share applications without any modifications. Starting with the 12c version, WebLogic now understands natively GlassFish deployment descriptors and specific configurations in order to offer you a truly and reliable migration path from a community Java EE application server to a enterprise middleware product like WebLogic. JBoss EAP 6 on the other hand has no support to natively reuse an existing (or still in development) application from JBoss AS community server. Users of JBoss suffer of critical issues during deployment time that includes: changing the libraries and dependencies of the application, patching the DTD or XSD deployment descriptors, refactoring of the application layers due classloading issues and anomalies, rebuilding of persistence, business and web layers due issues with "usage of the certified version of an certain dependency" or "frameworks that Red Hat potentially does not recommend" etc. If you have the culture or enterprise IT directive of developing Java EE applications using community middleware to in a certain future, transition to enterprise (supported by a vendor) middleware, Oracle WebLogic plus Oracle GlassFish offers you a more sustainable solution. - WebLogic Server 12c has a very light ZIP distribution (less than 165 MB). JBoss EAP 6 ZIP size is around 130 MB, together with JBoss ON you have more 100 MB resulting in a higher download footprint. This is particularly interesting if you plan to use automated setup of application server instances (for example, to rapidly setup a development or staging environment) using Maven or Hudson. - WebLogic Server 12c has a complete integration with Maven allowing developers to setup WebLogic domains with few commands. Tasks like downloading WebLogic, installation, domain creation, data sources deployment are completely integrated. JBoss EAP 6 on the other hand has a limited offer integration with those tools.  - WebLogic Server 12c has a startup mode called WLX that turns-off EJB, JMS and JCA containers leaving enabled only the web container with Java EE 6 web profile. JBoss EAP 6 on the other hand has no such feature, you need to disable manually the containers that you do not want to use. - WebLogic Server 12c supports fastswap, which enables you to change classes without redeployment. This is particularly interesting if you are developing patches for the application that is already deployed and you do not want to redeploy the entire application. This is the same behavior that most application servers offers to JSP pages, but with WebLogic Server 12c, you have the same feature for Java classes in general. JBoss EAP 6 on the other hand has no such support. Even JBoss EAP 5 does not support this until now. 8) JMS and Messaging - WebLogic Server 12c has a proven and high scalable JMS implementation since its initial release in 1995. JBoss EAP 6 on the other hand has a still immature technology called HornetQ, which was introduced in JBoss EAP 5 replacing everything that was implemented in the previous versions. Red Hat loves to introduce new technologies across JBoss versions, playing around with customers and their investments. And when they are asked about why they have changed the implementation and caused such a mess, their answer is always: "the previous implementation was inadequate and not aligned with the community strategy so we are creating a new a improved one". This Red Hat practice leads to uncomfortable investments that in a near future (sometimes less than a year) will be affected in someway. - WebLogic Server 12c has troubleshooting and monitoring features included on the WebLogic console and WLDF. JBoss EAP 6 on the other hand has no direct monitoring on the console, activity is reflected only on the logs, no debug logs available in case of JMS issues. - WebLogic Server 12c has extremely good performance and scalability. JBoss EAP 6 on the other hand has a JMS storage mechanism relying on Oracle database or MySQL. This means that if an issue in production happens and Red Hat affirms that an performance issue is happening due to database problems, they will not support you on the performance issue. They will orient you to call Oracle instead. - WebLogic Server 12c supports messaging enterprise features like SAF ("Store and Forward"), Distributed Queues/Topics and Foreign JMS providers support that leverage JMS implementations without compromise developer code making things completely transparent. JBoss EAP 6 on the other hand do not even dream to support such features. 9) Caching and Grid - Coherence, which is the leading and most mature data grid technology from Oracle, is available since early 2000 and was integrated with WebLogic in 2009. Coherence and WebLogic clusters can be both managed from WebLogic administrative console. Even Node Manager supports Coherence. JBoss on the other hand discontinued JBoss Cache, which was their caching implementation just like they did with the messaging implementation (JBossMQ) which was a issue for long term customers. JBoss EAP 6 ships InfiniSpan version 1.0 which is immature and lack a proven record of successful cases and reliability. - WebLogic Server 12c has a feature called ActiveCache which uses Coherence to, without any code changes, replicate HTTP sessions from both WebLogic and other application servers like JBoss, Tomcat, Websphere, GlassFish and even Microsoft IIS. JBoss EAP 6 on the other hand does have such support and even when they do in the future, they probably will support only their own application server. - Coherence can be used to manage both L1 and L2 cache levels, providing support to Oracle TopLink and others JPA compliant implementations, even Hibernate. JBoss EAP 6 and Infinispan on the other hand supports only Hibernate. And most important of all: Infinispan does not have any successful case of L1 or L2 caching level support using Hibernate, which lead us to reflect about its viability. 10) Performance - WebLogic Server 12c is certified with Oracle Exalogic Elastic Cloud and can run unchanged applications at this engineered system. This approach can benefit customers from Exalogic optimization's of both kernel and JVM layers to boost performance in terms of 10X for web, OLTP, JMS and grid applications. JBoss EAP 6 on the other hand has no investment on engineered systems: customers do not have the choice to deploy on a Java ultra fast system if their project becomes relevant and performance issues are detected. - WebLogic Server 12c maintains a performance gain across each new release: starting on WebLogic 5.1, the overall performance gain has been close to 4X, which close to a 20% gain release by release. JBoss on the other hand does not provide SPECJAppServer or SPECJEnterprise performance benchmarks. Their so called "performance gains" remains hidden in their customer environments, which lead us to think if it is true or not since we will never get access to those environments. - WebLogic Server 12c has industry performance benchmarks with submissions across platforms and configurations leading SPECJ. Oracle WebLogic leads SPECJAppServer performance in multiple categories, fitting all customer topologies like: dual-node, single-node, multi-node and multi-node with RAC. JBoss... again, does not provide any SPECJAppServer performance benchmarks. - WebLogic Server 12c has a feature called work manager which allows your application to embrace new performance levels based on critical resource utilization of the CPUs usage. Work managers prioritizes work and allocates threads based on an execution model that takes into account administrator-defined parameters and actual run-time performance and throughput. JBoss EAP 6 on the other hand has no compared feature and probably they never will. Not supporting such feature like work managers, JBoss EAP 6 forces admin people and specially developers to uncover performance gains in a intrusive way, rewriting the code and doing performance refactorings. 11) Professional Services Support - WebLogic Server 12c and any other technology sold by Oracle give customers the possibility of hire OCS ("Oracle Consulting Services") to manage critical scenarios, deployment assistance of new applications, high skilled consultancy of architecture, best practices and people allocation together with customer teams. All OCS services are available without any restrictions, having the customer bought software from Oracle or just starting their implementation before any acquisition. JBoss EAP 6 or Red Hat to be more specifically, only offers professional services if you buy subscriptions from them. If you are developing a new critical application for your business and need the help of Red Hat for a serious issue or architecture decision, they will probably say: "OK... I can help you but after you buy subscriptions from me". Red Hat also does not allows their professional services consultants to manage environments that uses community based software. They will probably force you to first buy a subscription, download their "enterprise" version and them, optionally hire their consultants. - Oracle provides you our university to educate your team into our technologies, including of course specialized trainings of WebLogic application server. At any time and location, you can hire Oracle to train your team so you get trustful knowledge according to your specific needs. Certifications for the products are also available if your technical people desire to differentiate themselves as professionals. Red Hat on the other hand have a limited pool of resources to train your team in their technologies. Basically they are selling training and certification for RHEL ("Red Hat Enterprise Linux") but if you demand more specialized training in JBoss middleware, they will probably connect you to some "certified" partner localized training since they are apparently discontinuing their education center, at least here in Brazil. They were not able to reproduce their success with RHEL education to their middleware division since they need first sell the subscriptions to after gives you specialized training. And again, they only offer you specialized training based on their enterprise version (EAP in the case of JBoss) which means that the courses will be a quite outdated. There are reports of developers that took official training's from Red Hat at this year (2012) and in a certain JBoss advanced course, Red Hat supposedly covered JBossMQ as the messaging subsystem, and even the printed material provided was based on JBossMQ since the training was created for JBoss EAP 4.3. 12) Encouraging Transparency without Ulterior Motives - WebLogic Server 12c like any other software from Oracle can be downloaded any time from anywhere, you should only possess an OTN ("Oracle Technology Network") credential and you can download any enterprise software how many times you want. And is not some kind of "trial" version. It is the official binaries that will be running for ever in your data center. Oracle does not encourages the usage of "specific versions" of our software. The binaries you buy from Oracle are the same binaries anyone in the world could download and use for testing and personal education. JBoss EAP 6 on the other hand are not available for download unless you buy a subscription and get access to the Red Hat enterprise repositories. If you need to test, learn or just start creating your application using Red Hat's middleware software, you should download it from the community website. You are not allowed to download the enterprise version that, according to Red Hat are more secure, reliable and robust. But no one of us want to start the development of a software with an unsecured, unreliable and not scalable middleware right? So what you do? You are "invited" by Red Hat to buy subscriptions from them to get access to the "cool" version of the software. - WebLogic Server 12c prices are publicly available in the Oracle website. If you want to know right now how much WebLogic will cost to your organization, just click here and get access to our price list. In the case of WebLogic, check out the "US Oracle Technology Commercial Price List". Oracle also encourages you to get in touch with a sales representative to discuss discounts that would make possible the investment into our technology. But you are not required to do this, only if you are interested in buying our technology or maybe you want to discuss some discount scenarios. JBoss EAP 6 on the other hand does not have its cost publicly available in Red Hat's website or in any other media, at least is not so easy to get such information. The only link you will possibly find in their website is a "Contact a Sales Representative" link. This is not a very good relationship between an customer and an vendor. This is not an example of transparency, mainly when the software are sold as open. In this situations, customers expects to see the software prices publicly available, so they can have the chance to decide, based on the existing features of the software, if the cost is fair or not. Conclusion Oracle WebLogic is the most mature, secure, reliable and scalable Java EE application server of the market, and have a proven record of success around the globe to prove it's majority. Don't lose the chance to discover today how WebLogic could fit your needs and sustain your global IT middleware strategy, no matter if your strategy are completely based on the Cloud or not.

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  • Big Data – Buzz Words: What is NoSQL – Day 5 of 21

    - by Pinal Dave
    In yesterday’s blog post we explored the basic architecture of Big Data . In this article we will take a quick look at one of the four most important buzz words which goes around Big Data – NoSQL. What is NoSQL? NoSQL stands for Not Relational SQL or Not Only SQL. Lots of people think that NoSQL means there is No SQL, which is not true – they both sound same but the meaning is totally different. NoSQL does use SQL but it uses more than SQL to achieve its goal. As per Wikipedia’s NoSQL Database Definition – “A NoSQL database provides a mechanism for storage and retrieval of data that uses looser consistency models than traditional relational databases.“ Why use NoSQL? A traditional relation database usually deals with predictable structured data. Whereas as the world has moved forward with unstructured data we often see the limitations of the traditional relational database in dealing with them. For example, nowadays we have data in format of SMS, wave files, photos and video format. It is a bit difficult to manage them by using a traditional relational database. I often see people using BLOB filed to store such a data. BLOB can store the data but when we have to retrieve them or even process them the same BLOB is extremely slow in processing the unstructured data. A NoSQL database is the type of database that can handle unstructured, unorganized and unpredictable data that our business needs it. Along with the support to unstructured data, the other advantage of NoSQL Database is high performance and high availability. Eventual Consistency Additionally to note that NoSQL Database may not provided 100% ACID (Atomicity, Consistency, Isolation, Durability) compliance.  Though, NoSQL Database does not support ACID they provide eventual consistency. That means over the long period of time all updates can be expected to propagate eventually through the system and data will be consistent. Taxonomy Taxonomy is the practice of classification of things or concepts and the principles. The NoSQL taxonomy supports column store, document store, key-value stores, and graph databases. We will discuss the taxonomy in detail in later blog posts. Here are few of the examples of the each of the No SQL Category. Column: Hbase, Cassandra, Accumulo Document: MongoDB, Couchbase, Raven Key-value : Dynamo, Riak, Azure, Redis, Cache, GT.m Graph: Neo4J, Allegro, Virtuoso, Bigdata As of now there are over 150 NoSQL Database and you can read everything about them in this single link. Tomorrow In tomorrow’s blog post we will discuss Buzz Word – Hadoop. 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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  • What&rsquo;s new in VS.10 &amp; TFS.10?

    - by johndoucette
    Getting my geek on… I have decided to call the products VS.10 (Visual Studio 2010), TP.10 (Test Professional 2010),  and TFS.10 (Team Foundation Server 2010) Thanks Neno Loje. What's new in Visual Studio & Team Foundation Server 2010? Focusing on Visual Studio Team System (VSTS) ALM-related parts: Visual Studio Ultimate 2010 NEW: IntelliTrace® (aka the historical debugger) NEW: Architecture Tools New Project Type: Modeling Project UML Diagrams UML Use Case Diagram UML Class Diagram UML Sequence Diagram (supports reverse enginneering) UML Activity Diagram UML Component Diagram Layer Diagram (with Team Build integration for layer validation) Architecuture Explorer Dependency visualization DGML Web & Load Tests Visual Studio Premium 2010 NEW: Architecture Tools Read-only model viewer Development Tools Code Analysis New Rules like SQL Injection detection Rule Sets Code Profiler Multi-Tier Profiling JScript Profiling Profiling applications on virtual machines in sampling mode Code Metrics Test Tools Code Coverage NEW: Test Impact Analysis NEW: Coded UI Test Database Tools (DB schema versioning & deployment) Visual Studio Professional 2010 Debuger Mixed Mode Debugging for 64-bit Applications Export/Import of Breakpoints and data tips Visual Studio Test Professional 2010 Microsoft Test Manager (MTM, formerly known as "Camano")) Fast Forward Testing Visual Studio Team Foundation Server 2010 Work Item Tracking and Project Management New MSF templatesfor Agile and CMMI (V 5.0) Hierarchical Work Items Custom Work Item Link Types Ready to use Excel agile project management workbooks for managing your backlogs (including capacity planing) Convert Work Item query to an Excel report MS Excel integration Support for Work Item hierarchies Formatting is preserved after doing a 'Refresh' MS Project integration Hierarchy and successor/predecessor info is now synchronized NEW: Test Case Management Version Control Public Workspaces Branch & Merge Visualization Tracking of Changesets & Work Items Gated Check-In Team Build Build Controllers and Agents Workflow 4-based build process NEW: Lab Management (only a pre-release is avaiable at the moment!) Project Portal & Reporting Dashboards (on SharePoint Portal) Burndown Chart TFS Web Parts (to show data from TFS) Administration & Operations Topology enhancements Application tier network load balancing (NLB) SQL Server scale out Improved Sharepoint flexibility Report Server flexibility Zone support Kerberos support Separation of TFS and SQL administration Setup Separate install from configure Improved installation wizards Optional components Simplified account requirements Improved Reporting Services configuration Setup consolidation Upgrading from previous TFS versions Improved IIS flexibility Administration Consolidation of command line tools User rename support Project Collections Archive/restore individual project collections Move Team Project Collections Server consolidation Team Project Collection Split Team Project Collection Isolation Server request cancellation Licensing: TFS server license included in MSDN subscriptions Removed features (former features not part of Visual Studio 2010): Debug » Start With Application Verifier Object Test Bench IntelliSense for C++ / CLI Debugging support for SQL 2000

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  • SBUG Session: The Enterprise Cache

    - by EltonStoneman
    [Source: http://geekswithblogs.net/EltonStoneman] I did a session on "The Enterprise Cache" at the UK SOA/BPM User Group yesterday which generated some useful discussion. The proposal was for a dedicated caching layer which all app servers and service providers can hook into, sharing resources and common data. The architecture might end up like this: I'll update this post with a link to the slide deck once it's available. The next session will have Udi Dahan walking through nServiceBus, register on EventBrite if you want to come along. Synopsis Looked at the benefits and drawbacks of app-centric isolated caches, compared to an enterprise-wide shared cache running on dedicated nodes; Suggested issues and risks around caching including staleness of data, resource usage, performance and testing; Walked through a generic service cache implemented as a WCF behaviour – suitable for IIS- or BizTalk-hosted services - which I'll be releasing on CodePlex shortly; Listed common options for cache providers and their offerings. Discussion Cache usage. Different value propositions for utilising the cache: improved performance, isolation from underlying systems (e.g. service output caching can have a TTL large enough to cover downtime), reduced resource impact – CPU, memory, SQL and cost (e.g. caching results of paid-for services). Dedicated cache nodes. Preferred over in-host caching provided latency is acceptable. Depending on cache provider, can offer easy scalability and global replication so cache clients always use local nodes. Restriction of AppFabric Caching to Windows Server 2008 not viewed as a concern. Security. Limited security model in most cache providers. Options for securing cache content suggested as custom implementations. Obfuscating keys and serialized values may mean additional security is not needed. Depending on security requirements and architecture, can ensure cache servers only accessible to cache clients via IPsec. Staleness. Generally thought to be an overrated problem. Thinking in line with eventual consistency, that serving up stale data may not be a significant issue. Good technical arguments support this, although I suspect business users will be harder to persuade. Providers. Positive feedback for AppFabric Caching – speed, configurability and richness of the distributed model making it a good enterprise choice. .NET port of memcached well thought of for performance but lack of replication makes it less suitable for these shared scenarios. Replicated fork – repcached – untried and less active than memcached. NCache also well thought of, but Express version too limited for enterprise scenarios, and commercial versions look costly compared to AppFabric.

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  • Too Few Women in IT!

    - by Yolande
    Last year, only 1% of attendees at Devoxx were women . This year, Devoxx addressed the issue in a panel entitled "Why We Should Target Women." On the panel were Kim Ross, Régina ten Bruggencate, Trisha Gee, Antonio Goncalves and Claude Falguiére. The moderator was Martijn Verburg. The discussion focused on how to attract women to programming and how to get current women programmers to be more active in the community. The panelists agreed that the IT field should not just attract more women but also men of different ethnic backgrounds. The lack of women in programming is in part a cultural issue that differs from region to region. In developed countries, very few women work as programmers whereas in Brazil and India a lot of women pursue careers in IT.  Women in developed countries perceive the field as isolating and very few young women graduate in computer science.  This perception of isolation was based in reality decades ago, but that is no longer the case today. Main ideas discussed by the panel: - Parents should encourage their daughters to play with Lego and learn programming - More organizations should target girls in high schools and young women in university to expose them to programming.  Duchess organization is planning on being more involved with young girl events and mentoring. - Women tend to be more self-critical about their skills and are intimidated by high skill requirements in job advertisements. Companies should change job advertisements to get more women to interviews. - Panelists don't recommend affirmative action because women feel favored and lose credibility. They want to be judged for their skills. - Panelists recommend acting the same way when dealing with either female or male co-workers and managers - Women need mentors (men or women) to learn to become speakers at conferences and to promote themselves better - Men should be sensitive to the fact that women are alone at work to respond to men teasing. The balance of power at work is different from a social setting. - Men also experience discrimination on the job. It is more difficult for men to take time off when their children are sick, for example. Equal valuing of parental obligations could result in equal pay for women. See also: Trisha Gee Blog - http://mechanitis.blogspot.com/ Duchess Organization - http://www.jduchess.org/

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  • Why lock statements don't scale

    - by Alex.Davies
    We are going to have to stop using lock statements one day. Just like we had to stop using goto statements. The problem is similar, they're pretty easy to follow in small programs, but code with locks isn't composable. That means that small pieces of program that work in isolation can't necessarily be put together and work together. Of course actors scale fine :) Why lock statements don't scale as software gets bigger Deadlocks. You have a program with lots of threads picking up lots of locks. You already know that if two of your threads both try to pick up a lock that the other already has, they will deadlock. Your program will come to a grinding halt, and there will be fire and brimstone. "Easy!" you say, "Just make sure all the threads pick up the locks in the same order." Yes, that works. But you've broken composability. Now, to add a new lock to your code, you have to consider all the other locks already in your code and check that they are taken in the right order. Algorithm buffs will have noticed this approach means it takes quadratic time to write a program. That's bad. Why lock statements don't scale as hardware gets bigger Memory bus contention There's another headache, one that most programmers don't usually need to think about, but is going to bite us in a big way in a few years. Locking needs exclusive use of the entire system's memory bus while taking out the lock. That's not too bad for a single or dual-core system, but already for quad-core systems it's a pretty large overhead. Have a look at this blog about the .NET 4 ThreadPool for some numbers and a weird analogy (see the author's comment). Not too bad yet, but I'm scared my 1000 core machine of the future is going to go slower than my machine today! I don't know the answer to this problem yet. Maybe some kind of per-core work queue system with hierarchical work stealing. Definitely hardware support. But what I do know is that using locks specifically prevents any solution to this. We should be abstracting our code away from the details of locks as soon as possible, so we can swap in whatever solution arrives when it does. NAct uses locks at the moment. But my advice is that you code using actors (which do scale well as software gets bigger). And when there's a better way of implementing actors that'll scale well as hardware gets bigger, only NAct needs to work out how to use it, and your program will go fast on it's own.

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