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• C#: Resource file refactoring

  - by Svish

  Does anyone know of a good tool for refactoring resources in a visual studio 2008 solution? We have a number of resource files with translated text in an assembly used for localizing our application. But they have gotten a bit messy... I would like to rename some of the keys, and move some of them into other resource files. And I would like those changes be done in my code, and the translated versions of the resource files as well. Maybe a some analysis on what strings are missing in the translated versions, and what strings have been removed from the original as well... Does anyone know of a good visual studio extension or ReSharper plugin that can help me with this? Right now it is kind of a pain, because I have to first rename the key in the base resource file, then in the localized versions. And then compile to get all the compile errors resulting from the key which now have a different name, and then go through and fix them all... very annoying =/

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• including .h files.

  - by Max

  Suppose I have two .h files: A.h and B.h. Moreover, A.h includes B.h itself: B.h - declares class B. class B { ... }; A.h - declares class A, which uses class B. #include B.h class A { void SomeFunction(const B& b); }; Now, I have some .cpp file, that uses both A and B classes (B class maybe used not only in A::SomeFunction(B)) What are the pluses to include both A.h and B.h (instead of only A.h) from the perspective of design-patterns and coding style.

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• Running interrelated methods continously using java

  - by snehalata

  I have written application which downloads data from a website every 10 mins and writes to a file.Then these files are merged into one file and then R program is run on this merged file to perform sentiment analysis and result is stored in hbase. I want the process of merging files,running R and then storing to HBase to run continuosly on the downloaded data. For running R,we are running R script from java program.We have used Runtime.getRuntime().exec() method to run R program but it doesn't wait for R program to complete and method in the next line starts executing.Using p.waitFor() did not help . What approach should I use to do merge then run R and finally store results in Hbase?Should I use timer class??

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• Singleton design potential leak

  - by iBrad Apps

  I have downloaded a library off of github and have noticed that in the main singleton of the library there is a possible leak in this bit of code: +(DDGameKitHelper*) sharedGameKitHelper { @synchronized(self) { if (instanceOfGameKitHelper == nil) { [[DDGameKitHelper alloc] init]; } return instanceOfGameKitHelper; } return nil; } Now obviously there is no release or autorelease anywhere so I must do it but how and in what way properly? I have looked at various Singleton design patterns on the Internet and they just assign, in this case, instanceOfGameKitHelper to the alloc and init line. Anyway how would I properly fix this? Thanks!

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• <div class="headerFst"> What is this?

  - by Jessica

  I have been attempting to remove a repeating header on all of my webpages for customization purposes, but have been unsuccessful finding what is causing this header repeat. I came across this code in the header, and after researching it, I can not find what its purpose is. Could this be my culprit for the repeating patterns? If not, please point me to the right direction. Here is the hmtl: <!--container--> <div id="container"> <div id="header"> <!--headerFst--> <div class="headerFst"> and here it is in look.css: div.headerFst { float:left; width:980px; padding-top:5px; } Thank you for viewing, and helping if possible.

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• Oracle: Difference in execution plans between databases

  - by Will

  Hello, I am comparing queries my development and production database. They are both Oracle 9i, but almost every single query has a completely different execution plan depending on the database. All tables/indexes are the same, but the dev database has about 1/10th the rows for each table. On production, the query execution plan it picks for most queries is different from development, and the cost is somtimes 1000x higher. Queries on production also seem to be not using the correct indexes for queries in some cases (full table access). I have ran dbms_utility.analyze schema on both databases recently as well in the hopes the CBO would figure something out. Is there some other underlying oracle configuration that could be causing this? I am a developer mostly so this kind of DBA analysis is fairly confusing at first..

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• Unity3D draw call optimization : static batching VS manually draw mesh with MaterialPropertyBlock

  - by Heisenbug

  I've read Unity3D draw call batching documentation. I understood it, and I want to use it (or something similar) in order to optimize my application. My situation is the following: I'm drawing hundreds of 3d buildings. Each building can be represented using a Mesh (or a SubMesh for each building, but I don't thing this will affect performances) Each building can be textured with several combinations of texture patterns(walls, windows,..). Textures are stored into an Atlas for optimizaztion (see Texture2d.PackTextures) Texture mapping and facade pattern generation is done in fragment shader. The shader can be the same (except for few values) for all buildings, so I'd like to use a sharedMaterial in order to optimize parameters passed to the GPU. The main problem is that, even if I use an Atlas, share the material, and declare the objects as static to use static batching, there are few parameters(very fews, it could be just even a float I guess) that should be different for every draw call. I don't know exactly how to manage this situation using Unity3D. I'm trying 2 different solutions, none of them completely implemented. Solution 1 Build a GameObject for each building building (I don't like very much the overhead of a GameObject, anyway..) Prepare each GameObject to be static batched with StaticBatchingUtility.Combine. Pack all texture into an atlas Assign the parent game object of combined batched objects the Material (basically the shader and the atlas) Change some properties in the material before drawing an Object The problem is the point 5. Let's say I have to assign a different id to an object before drawing it, how can I do this? If I use a different material for each object I can't benefit of static batching. If I use a sharedMaterial and I modify a material property, all GameObjects will reference the same modified variable Solution 2 Build a Mesh for every building (sounds better, no GameObject overhead) Pack all textures into an Atlas Draw each mesh manually using Graphics.DrawMesh Customize each DrawMesh call using a MaterialPropertyBlock This would solve the issue related to slightly modify material properties for each draw call, but the documentation isn't clear on the following point: Does several consecutive calls to Graphic.DrawMesh with a different MaterialPropertyBlock would cause a new material to be instanced? Or Unity can understand that I'm modifying just few parameters while using the same material and is able to optimize that (in such a way that the big atlas is passed just once to the GPU)?

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• Windows Azure Learning Plan - Security

  - by BuckWoody

  This is one in a series of posts on a Windows Azure Learning Plan. You can find the main post here. This one deals with Security for  Windows Azure.   General Security Information Overview and general  information about Windows Azure Security - what it is, how it works, and where you can learn more. General Security Whitepaper – answers most questions http://blogs.msdn.com/b/usisvde/archive/2010/08/10/security-white-paper-on-windows-azure-answers-many-faq.aspx Windows Azure Security Notes from the Patterns and Practices site http://blogs.msdn.com/b/jmeier/archive/2010/08/03/now-available-azure-security-notes-pdf.aspx Overview of Azure Security http://www.windowsecurity.com/articles/Microsoft-Azure-Security-Cloud.html Azure Security Resources http://reddevnews.com/articles/2010/08/19/microsoft-releases-windows-azure-security-resources.aspx Cloud Computing Security Considerations http://www.microsoft.com/downloads/en/details.aspx?FamilyID=68fedf9c-1c27-4642-aa5b-0a34472303ea&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Security in Cloud Computing – a Microsoft Perspective http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7c8507e8-50ca-4693-aa5a-34b7c24f4579&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Physical Security for Microsoft’s Online Computing Information on the Infrastructure and Locations for Azure Physical Security. The Global Foundation Services Group at Microsoft handles physical security http://www.globalfoundationservices.com/security/index.html Microsoft’s Security Response Center http://www.microsoft.com/security/msrc/ Software Security for Microsoft’s Online Computing Steps we take as a company to develop secure software Windows Azure is developed using the Trustworthy Computing Initiative http://www.microsoft.com/about/twc/en/us/default.aspx and  http://msdn.microsoft.com/en-us/library/ms995349.aspx Identity and Access in the Cloud http://blogs.msdn.com/b/technology_titbits_by_rajesh_makhija/archive/2010/10/29/identity-and-access-in-the-cloud.aspx Security Steps you should take While Microsoft takes great pains to secure the infrastructure, platform and code for Windows Azure, you have a responsibility to write secure code. These pointers can help you do that. Securing your cloud architecture, step-by-step http://technet.microsoft.com/en-us/magazine/gg296364.aspx Security Guidelines for Windows Azure http://redmondmag.com/articles/2010/06/15/microsoft-issues-security-guidelines-for-windows-azure.aspx  Best Practices for Windows Azure Security http://blogs.msdn.com/b/vbertocci/archive/2010/06/14/security-best-practices-for-developing-windows-azure-applications.aspx Active Directory and Windows Azure http://blogs.msdn.com/b/plankytronixx/archive/2010/10/22/projecting-your-active-directory-identity-to-the-azure-cloud.aspx Understanding Encryption (great overview and tutorial) http://blogs.msdn.com/b/plankytronixx/archive/2010/10/23/crypto-primer-understanding-encryption-public-private-key-signatures-and-certificates.aspx Securing your Connection Strings (SQL Azure) http://blogs.msdn.com/b/sqlazure/archive/2010/09/07/10058942.aspx Getting started with Windows Identity Foundation (WIF) quickly http://blogs.msdn.com/b/alikl/archive/2010/10/26/windows-identity-foundation-wif-fast-track.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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• A Taxonomy of Numerical Methods v1

  - by JoshReuben

  Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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• Getting started with Blocks and namespaces - Enterprise Library 5.0 Tutorial Part 2

  This is my second post in this series. In first blog post I explained how to install Enterprise Library 5.0 and provided links to various resources. Enterprise Library is divided into various blocks. Simply we can say, a block is a ready made solution for a particular common problem across various applications. So instead focusing on implementation of common problem across various applications, we can reuse these fully tested and extendable blocks to increase the productivity and also extendibility as these blocks are made with good design principles and patterns. Major blocks of Enterprise Library 5.0 are as follows.   Core infrastructure Functional Application Blocks Caching Data Exception Handling Logging Security Cryptography Validation Wiring Application Blocks Unity Policy Injection/Interception   Each block resides in its own assembly, and also some extra assemblies for common infrastructure. Assemblies are as follows. Microsoft.Practices.EnterpriseLibrary.Caching.Cryptography.dll Microsoft.Practices.EnterpriseLibrary.Caching.Database.dll Microsoft.Practices.EnterpriseLibrary.Caching.dll Microsoft.Practices.EnterpriseLibrary.Common.dll Microsoft.Practices.EnterpriseLibrary.Configuration.Design.HostAdapter.dll Microsoft.Practices.EnterpriseLibrary.Configuration.Design.HostAdapterV5.dll Microsoft.Practices.EnterpriseLibrary.Configuration.DesignTime.dll Microsoft.Practices.EnterpriseLibrary.Configuration.EnvironmentalOverrides.dll Microsoft.Practices.EnterpriseLibrary.Data.dll Microsoft.Practices.EnterpriseLibrary.Data.SqlCe.dll Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.dll Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.Logging.dll Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.WCF.dll Microsoft.Practices.EnterpriseLibrary.Logging.Database.dll Microsoft.Practices.EnterpriseLibrary.Logging.dll Microsoft.Practices.EnterpriseLibrary.PolicyInjection.dll Microsoft.Practices.EnterpriseLibrary.Security.Cache.CachingStore.dll Microsoft.Practices.EnterpriseLibrary.Security.Cryptography.dll Microsoft.Practices.EnterpriseLibrary.Security.dll Microsoft.Practices.EnterpriseLibrary.Validation.dll Microsoft.Practices.EnterpriseLibrary.Validation.Integration.AspNet.dll Microsoft.Practices.EnterpriseLibrary.Validation.Integration.WCF.dll Microsoft.Practices.EnterpriseLibrary.Validation.Integration.WinForms.dll Microsoft.Practices.ServiceLocation.dll Microsoft.Practices.Unity.Configuration.dll Microsoft.Practices.Unity.dll Microsoft.Practices.Unity.Interception.dll Enterprise Library Configuration Tool In addition to these assemblies you would get configuration tool “EntLibConfig-32.exe”. If you are targeting your application to .NET 4.0 framework then you would need to use “EntLibConfig.NET4.exe”. Optionally you can install Visual Studio 2008 and Visual Studio 2010 add-ins whilst installing of Enterprise Library. So that you can invoke the enterprise Library configuration from Visual Studio by right clicking on “app.config” or “web.config” file as shown below. I would suggest you to download the documentation from Codeplex which was released on May 2010. It consists 3MB of information. you can also find issue tracker to know various issues/bugs currently people talking about enterprise library. There is also discussion link takes you to community site where you can post your questions. In my next blog post, I would cover more on each block. span.fullpost {display:none;}

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• Force.com presents Database.com SQL Azure/Amazon RDS unfazed

  - by Sarang

  At the DreamForce 2010 event in San Francisco Force.com unveiled their next big thing in the Fat SaaS portfolio "Database.com".  I am still wondering how would they would've shelled out for that domain name. Now why would a already established SaaS player foray into a key building block like Database? Potentially allowing enterprises to build apps that do not utilize the Force.com stack! One key reason is being seen as the Fat SaaS player with evey trick in the SaaS space under his belt. You want CRM come hither, want a custom development PaaS like solution welcome home (VMForce), want all your apps to talk to a cloud DB and minimize latency by having it reside closer to you cloud apps? You've come to the right place sire! Other is potentially killing foray of smaller DB players like Oracle (Not surprisingly, the Database.com offering is a highly customized and scalable Oracle database) from entering the lucrative SaaS db marketplace. The feature set promised looks great out of the box for someone who likes to visualize cool new architectures. The ground realities are certainly going to be a lot different considering the SOAP/REST style access patterns in lieu of the comfortable old shoe of SQL. Microsoft suffered heavily with SDS (SQL Data Services) offering in early 2009 and had to pull the plug on the product only to reintroduce as a simple SQL Server in the cloud, SQL Windows Azure. Though MSFT is playing cool by providing OData semantics to work with SQL Windows Azure satisfying atleast some needs of the Web-Style to a DB. The other features like Social data models including Profiles, Status updates, feeds seem interesting as well. (Although I beleive social is just one of the aspects of large scale collaborative computing). All these features start "Free" for devs its a good news but the good news stops here. The overall pricing model of $ per Users per Transactions / Month is highly disproportionate compared to Amazon RDS (Based on MySQL) or SQL Windows Azure (Based on MSSQL). Roger Jennigs of Oakleaf did an interesting comparo based on 3, 10, 100, 500 users and it turns out that Database.com going by current understanding is way too expensive for the services on offer. The offering may not impact the decision for DotNet shops mulling their cloud stategy or even some Java/MySQL shops thinking about Amazon RDS, however for enterprises having already invested in other force.com offerings this could be a very important piece in the cloud strategy jigsaw. One which would address a key cloud DB issue of "Latency" for them at least it will help having the DB in the neighborhood. The tooling and "SQL like" access provider drivers (Think ODBC/JDBC) will be available later this year. Progress Software has already announced their JDBC driver stack for Database.com. It remains to be seen how effective the overall solutions proves to be in the longer run but for starts its a important decision towards consolidating Force.com's already strong positioning in the SaaS space. As always contrasting views are welcome! :)

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• Are you cashing in on the MVP complimentary subscriptions ?

  - by Tarun Arora

  The two most asked questions in the Microsoft technology communities around the Microsoft MVP program are, 1. How do I become a Microsoft MVP? 2. What benefits do I get as an MVP? The answer to the first question has been well answered here. In this blog post, I’ll try and answer the second question.           Please find a comprehensive list of Not for Resale personal subscriptions of various products that Microsoft MVP’s are eligible for Product Description Details JetBrains Resharper, dotTrace, dotCover & WebStorm  https://www.jetbrains.com/resharper/buy/mvp.html RedGate Sql server development, database administration, .net development, azure development (merged with Cerebrata), mySQL development, Oracle development http://www.red-gate.com/community/mvp-program Pluralsight Pluralsight on demand training http://blog.pluralsight.com/2011/02/28/pluralsight-for-mvp/ Cerebrata Cloud storage studio and Azure Diagnostic Manager (part of redgate now) https://www.cerebrata.com/Offers/mvp.aspx Telerik Telerik Ultimate collection & Telerik TeamPulse http://blogs.telerik.com/blogs/posts/11-03-01/telerik-gift-for-microsoft-mvps.aspx Developer Express DevEx controls http://www.devexpress.com/Home/Community/mvp.xml InnerWorking 600 hours of .net training catalogue http://www.innerworkings.com/mvp Typemock Typemock Isolator, Typemock Isolator for Sharepoint developers, Typemock Isolator for web developers, TestDriven.NET http://www.typemock.com/mvp SpeakFlow A suite of tools for creating, managing, and delivering non-linear presentations http://www.speakflow.com/ TechSmith Camtasia Studio, SnagIt, screen cast http://www.techsmith.com/camtasia.html Altova Altova XML spy http://www.altova.com/xml-editor/ Visual SVN VisualSVN Subversion integration plug-in for Visual Studio http://www.visualsvn.com/visualsvn/purchase/mvp/ PreEmptive Solution Professional PreEmptive Analytics, Dotfuscator http://www.preemptive.com/landing/mvp Armadillo Armadillo Adaptive Bug Prevention http://www.armadilloverdrive.com/ IS Decisions NFR license to Userlock, RemoteExec, FileAudit & WinReporter http://www.isdecisions.com/download/mvp-mct-program.htm Idera SQL tools http://www.idera.com/Content/Home.aspx West Wind Help Builder Help builder solution http://www.west-wind.com/weblog/posts/2005/Mar/09/Are-you-a-Microsoft-MVP-Get-a-FREE-copy-of-West-Wind-Html-Help-Builder Bamboo Sharepoint tools http://community.bamboosolutions.com/blogs/partner-advantage-program/archive/2008/08/01/partner-advantage-program-mvp.aspx Nitriq Nitriq code analysis http://blog.nitriq.com/FreeLicensesForMicrosoftMVPs.aspx ByteScout Components, Libraries and Developer Tools http://bytescout.com/buy/purchase_nfr_for_mvp.html YourKit Java and .net Profiler http://yourkit.com/.net/profiler/index.jsp Aspose .NET components http://www.aspose.com/corporate/community/2012_05_08_nfr-licenses-for-community-leaders.aspx Apart from google bing fu; stackoverflow and breathtech were a great help in compiling the above list. If you know of any other benefits, offers or complimentary subscriptions on offer for MVPs not cover in the list above, please add to the comment thread and I’ll have it updated in the list. Enjoy

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• URL Routing in ASP.NET 4.0

  In the .NET Framework 3.5 SP1, Microsoft introduced ASP.NET Routing, which decouples the URL of a resource from the physical file on the web server. With ASP.NET Routing you, the developer, define routing rules map route patterns to a class that generates the content. For example, you might indicate that the URL Categories/CategoryName maps to a class that takes the CategoryName and generates HTML that lists that category's products in a grid. With such a mapping, users could view products for the Beverages category by visiting www.yoursite.com/Categories/Beverages. In .NET 3.5 SP1, ASP.NET Routing was primarily designed for ASP.NET MVC applications, although as discussed in Using ASP.NET Routing Without ASP.NET MVC it is possible to implement ASP.NET Routing in a Web Forms application, as well. However, implementing ASP.NET Routing in a Web Forms application involves a bit of seemingly excessive legwork. In a Web Forms scenario we typically want to map a routing pattern to an actual ASP.NET page. To do so we need to create a route handler class that is invoked when the routing URL is requested and, in a sense, dispatches the request to the appropriate ASP.NET page. For instance, to map a route to a physical file, such as mapping Categories/CategoryName to ShowProductsByCategory.aspx - requires three steps: (1) Define the mapping in Global.asax, which maps a route pattern to a route handler class; (2) Create the route handler class, which is responsible for parsing the URL, storing any route parameters into some location that is accessible to the target page (such as HttpContext.Items), and returning an instance of the target page or HTTP Handler that handles the requested route; and (3) writing code in the target page to grab the route parameters and use them in rendering its content. Given how much effort it took to just read the preceding sentence (let alone write it) you can imagine that implementing ASP.NET Routing in a Web Forms application is not necessarily the most straightforward task. The good news is that ASP.NET 4.0 has greatly simplified ASP.NET Routing for Web Form applications by adding a number of classes and helper methods that can be used to encapsulate the aforementioned complexity. With ASP.NET 4.0 it's easier to define the routing rules and there's no need to create a custom route handling class. This article details these enhancements. Read on to learn more! Read More >

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• Don&rsquo;t Forget! In-Memory Databases are Hot

  - by andrewbrust

  If you’re left scratching your head over SAP’s intention to acquire Sybase for almost $6 million, you’re not alone.  Despite Sybase’s 1990s reign as the supreme database standard in certain sectors (including Wall Street), the company’s flagship product has certainly fallen from grace.  Why would SAP pay a greater than 50% premium over Sybase’s closing price on the day of the announcement just to acquire a relational database which is firmly stuck in maintenance mode? Well there’s more to Sybase than the relational database product.  Take, for example, its mobile application platform.  It hit Gartner’s “Leaders’ Quadrant” in January of last year, and SAP needs a good mobile play.  Beyond the platform itself, Sybase has a slew of mobile services; click this link to look them over. There’s a second major asset that Sybase has though, and I wonder if it figured prominently into SAP’s bid: Sybase IQ.  Sybase IQ is a columnar database.  Columnar databases place values from a given database column contiguously, unlike conventional relational databases, which store all of a row’s data in close proximity.  Storing column values together works well in aggregation reporting scenarios, because the figures to be aggregated can be scanned in one efficient step.  It also makes for high rates of compression because values from a single column tend to be close to each other in magnitude and may contain long sequences of repeating values.  Highly compressible databases use much less disk storage and can be largely or wholly loaded into memory, resulting in lighting fast query performance.  For an ERP company like SAP, with its own legacy BI platform (SAP BW) and the entire range of Business Objects and Crystal Reports BI products (which it acquired in 2007) query performance is extremely important. And it’s a competitive necessity too.  QlikTech has built an entire company on a columnar, in-memory BI product (QlikView).  So too has startup company Vertica.  IBM’s TM1 product has been doing in-memory OLAP for years.  And guess who else has the in-memory religion?  Microsoft does, in the form of its new PowerPivot product.  I expect the technology in PowerPivot to become strategic to the full-blown SQL Server Analysis Services product and the entire Microsoft BI stack.  I sure don’t blame SAP for jumping on the in-memory bandwagon, if indeed the Sybase acquisition is, at least in part, motivated by that. It will be interesting to watch and see what SAP does with Sybase’s product line-up (assuming the acquisition closes), including the core database, the mobile platform, IQ, and even tools like PowerBuilder.  It is also fascinating to watch columnar’s encroachment on relational.  Perhaps this acquisition will be columnar’s tipping point and people will no longer see it as a fad.  Are you listening Larry Ellison?

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• What is Inversion of control and why we need it?

  - by Jalpesh P. Vadgama

  Most of programmer need inversion of control pattern in today’s complex real time application world. So I have decided to write a blog post about it. This blog post will explain what is Inversion of control and why we need it. We are going to take a real world example so it would be better to understand. The problem- Why we need inversion of control? Before giving definition of Inversion of control let’s take a simple real word example to see why we need inversion of control. Please have look on the following code. public class class1 { private class2 _class2; public class1() { _class2=new class2(); } } public class class2 { //Some implementation of class2 } I have two classes “Class1” and “Class2”.  If you see the code in that I have created a instance of class2 class in the class1 class constructor. So the “class1” class is dependent on “class2”. I think that is the biggest issue in real world scenario as if we change the “class2” class then we might need to change the “class1” class also. Here there is one type of dependency between this two classes that is called Tight Coupling. Tight coupling will have lots of problem in real world applications as things are tends to be change in future so we have to change all the tight couple classes that are dependent of each other. To avoid this kind of issue we need Inversion of control. What is Inversion of Control? According to the wikipedia following is a definition of Inversion of control. “In software engineering, Inversion of Control (IoC) is an object-oriented programming practice where the object coupling is bound at run time by an assembler object and is typically not known at compile time using static analysis.” So if you read the it carefully it says that we should have object coupling at run time not compile time where it know what object it will create, what method it will call or what feature it will going to use for that. We need to use same classes in such way so that it will not tight couple with each other. There are multiple way to implement Inversion of control. You can refer wikipedia link for knowing multiple ways of implementing Inversion of control. In future posts we are going to see all the different way of implementing Inversion of control.

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• Software Architecture and Software Architecture Evaluation

  How many of us have worked at places where the concept of software architecture was ridiculed for wasting time and money? Even more ridiculous to them was the concept of evaluating software architecture. I think the next time that I am in this situation again, and I hope that I never am I will have to push for this methodology in the software development life cycle. I have spent way too many hours/days/months/years working poorly architected systems or systems that were just built ADHOC. This in software development must stop. I can understand why systems get like this due to overzealous sales staff, demanding management that wants everything yesterday, and project managers asking if things are done yet before the project has even started. But seriously, some time must be spent designing the applications that we write along with evaluating the architecture so that it will integrate will within the existing systems of an origination. If placed in this situation again, I will strive to gain buying from key players within the business, for example: Senior Software Engineers\Developers, Software Architects, Project Managers, Software Quality Assurance, Technical Services, Operations, and Finance in order for this idea to succeed with upper management. In order to convince these key players I will have to show them the benefits of architecture and even more benefits of evaluating software architecture on a system wide level. Benefits of Software Architecture Evaluation Places Stakeholders in the Same Room to Communicate Ensures Delivery of Detailed Quality Goals Prioritizes Conflicting Goals Requires Clear Explication Improves the Quality of Documentation Discovers Opportunities for Cross-Project Reuse Improves Architecture Practices Once I had key player buy in then and only then would I approach upper management about my plan regarding implementing the concept of software architecture and using evaluation to ensure that the software being designed is the proper architecture for the project. In addition to the benefits listed above I would also show upper management how much time is being wasted by not doing these evaluations. For example, if project X cost us Y amount, then why do we have several implementations in various forms of X and how much money and time could we have saved if we just reused the existing code base to give each system the same functionality that was already created? After this, I would mention what would happen if we had 50 instances of this situation? Then I would show them how the software architecture evaluation process would have prevented this and that the optimization could have leveraged its existing code base to increase the speed and quality of its development. References:Carnegie Mellon Software Engineering Institute (2011). Architecture Tradeoff Analysis Method from http://www.sei.cmu.edu/architecture/tools/evaluate/atam.cfm

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• Administering Team Foundation Server 2010 Class resource links

  - by John Alexander

  Here are the resource links for the Administering Team Foundation Server 2010 Class from last week in Minneapolis.  Microsoft® Visual Studio® 2010 and Team Foundation Server® 2010 RTM virtual machine for Microsoft® Virtual PC 2007 SP1 http://www.microsoft.com/downloads/en/details.aspx?FamilyID=5e13b15a-fd74-4cd7-b53e-bdf9456855bd Microsoft® Visual Studio® 2010 and Team Foundation Server® 2010 RTM virtual machine for Windows Virtual PC http://www.microsoft.com/downloads/en/details.aspx?FamilyID=509c3ba1-4efc-42b5-b6d8-0232b2cbb26e Microsoft® Visual Studio® 2010 and Team Foundation Server® 2010 RTM virtual machine for Windows Server 2008 Hyper-V http://www.microsoft.com/downloads/en/details.aspx?FamilyID=e0198b64-4acb-4709-b07f-359fb4d523bc Customizable process guidance http://blogs.msdn.com/b/allclark/archive/2010/08/12/customizable-process-guidance.aspx The 5 most read Visual Studio ALM help topics on MSDN http://blogs.msdn.com/b/allclark/archive/2010/11/12/the-5-most-read-visual-studio-alm-help-topics-on-msdn.aspx Inside TFS http://visualstudiomagazine.com/Articles/List/Inside-TFS.aspx Testing Topics http://msdn.microsoft.com/en-us/library/dd286594.aspx Blogs http://community.accentient.com http://geekswithblogs.net Branching Guide http://tfsbranchingguideiii.codeplex.com/ Great VSTS blog http://geekswithblogs.net/hinshelm/Default.aspx My Blog :D http://geekswithblogs.net/jalexander/Default.aspx Visual Studio Forums http://bit.ly/fE16u3 TFS Migration and Integration Solutions http://bit.ly/cLaBnT TFS Migration and Integration Tools (VS ALM Rangers) http://bit.ly/9tHWdG TFS Migration and Integration Platform (CodePlex) http://tfsintegration.codeplex.com Team Foundation Server SDK http://code.msdn.microsoft.com/TfsSdk Migrate and Integration Forum http://bit.ly/f4Lnps Team Foundation Server Widgets http://www.tfswidgets.com TFS Sdk http://code.msdn.microsoft.com/TfsSdk TFS Migration and Integration Solutions http://bit.ly/cLaBnT TFS Integration Tools Forum http://bit.ly/f4Lnps TFS Integration Tools http://bit.ly/9tHWdG TFS Integration Platform http://tfsintegration.codeplex.com VS Upgrade Guide http://vs2010upgradeguide.codeplex.com Updating an Upgraded Team Project to Access New Features http://bit.ly/9cCcMP Team Foundation Power Tools http://bit.ly/dfNVQk Team Foundation Administration Tool http://tfsadmin.codeplex.com Using Team Foundation Server Command-Line Tools http://bit.ly/hCyozJ Changing Groups and Permissions with TFSSecurity http://bit.ly/esIjgw Unofficial Prep guide for TFS 2010 Administration Exam (70-512) http://geekswithblogs.net/enriquelima/archive/2010/07/21/unofficial-prep-guide-for-tfs-2010-administration-exam-70-512.aspx Another Prep Guide http://bit.ly/bpO30R Professional Application Lifecycle Management with VS 2010 Book http://bit.ly/9rCIRj Search CodePlex for TFS related apps http://www.codeplex.com/site/search Visual Studio Gallery http://visualstudiogallery.com TFS Widgets http://tfswidgets.com Migrate from Visual SourceSafe http://bit.ly/8XPSRh Team Foundation Server MSSCCI Provider 2010 http://bit.ly/dst1OQ Attrice TFS Sidekicks www.attrice.info/cm/tfs Hosted TFS http://bit.ly/cMZdvp Manually Processing the Team Foundation Server 2010 Data Warehouse and Analysis Services Database http://bit.ly/aG5oEh TFS 2005, 2008 and 2010 Compatibility http://shrinkster.com/1dhj

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• MVC Architecture

  Model-View-Controller (MVC) is an architectural design pattern first written about and implemented by  in 1978. Trygve developed this pattern during the year he spent working with Xerox PARC on a small talk application. According to Trygve, “The essential purpose of MVC is to bridge the gap between the human user's mental model and the digital model that exists in the computer. The ideal MVC solution supports the user illusion of seeing and manipulating the domain information directly. The structure is useful if the user needs to see the same model element simultaneously in different contexts and/or from different viewpoints.”  Trygve Reenskaug on MVC The MVC pattern is composed of 3 core components. Model View Controller The Model component referenced in the MVC pattern pertains to the encapsulation of core application data and functionality. The primary goal of the model is to maintain its independence from the View and Controller components which together form the user interface of the application. The View component retrieves data from the Model and displays it to the user. The View component represents the output of the application to the user. Traditionally the View has read-only access to the Model component because it should not change the Model’s data. The Controller component receives and translates input to requests on the Model or View components. The Controller is responsible for requesting methods on the model that can change the state of the model. The primary benefit to using MVC as an architectural pattern in a project compared to other patterns is flexibility. The flexibility of MVC is due to the distinct separation of concerns it establishes with three distinct components.  Because of the distinct separation between the components interaction is limited through the use of interfaces instead of classes. This allows each of the components to be hot swappable when the needs of the application change or needs of availability change. MVC can easily be applied to C# and the .Net Framework. In fact, Microsoft created a MVC project template that will allow new project of this type to be created with the standard MVC structure in place before any coding begins. The project also creates folders for the three key components along with default Model, View and Controller classed added to the project. Personally I think that MVC is a great pattern in regards to dealing with web applications because they could be viewed from a myriad of devices. Examples of devices include: standard web browsers, text only web browsers, mobile phones, smart phones, IPads, IPhones just to get started. Due to the potentially increasing accessibility needs and the ability for components to be hot swappable is a perfect fit because the core functionality of the application can be retained and the View component can be altered based on the client’s environment and the View component could be swapped out based on the calling device so that the display is targeted to that specific device.

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• Survey Probes the Project Management Concerns of Financial Services Executives

  - by Melissa Centurio Lopes

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Do you wonder what are the top reasons why large projects in the financial industry fail to meet budgets, schedules, and other key performance criteria? Being able to answer this question can provide important insight and value of good project management practices for your organization. According to 400 senior executives who participated in a new survey conducted by the Economist Intelligence Unit and sponsored by Oracle, unrealistic project goals is the main reason for roadblocks to success Other common stumbling blocks are poor alignment between project and organizational goals, inadequate human resources, lack of strong leadership, and unwillingness among team members to point out problems. This survey sample also had a lot to say about the impact of regulatory compliance on the overall portfolio management process. Thirty-nine percent acknowledged that regulations enabled efficient functioning of their businesses. But a similar number said that regulations often require more financial resources than were originally allocated to bring projects in on time. Regulations were seen by 35 percent of the executives as roadblocks to their ability to invest in the organization’s growth and success. These revelations among others are discussed in depth in a new on-demand Webcast titled “Too Good to Fail: Developing Project Management Expertise in Financial Services” now available from Oracle. The Webcast features Brian Gardner, editor of the Economist Intelligence Unit, who presents these findings from this survey along with Guy Barlow, director of industry strategy for Oracle Primavera. Together, they analyze what the numbers mean for project and program managers and the financial services industry. Register today to watch the on-demand Webcast and get a full rundown and analysis of the survey results. Take the Economist Intelligence Unit benchmarking survey and see how your views compare with those of other financial services industry executives in ensuring project success.  Read more in the October Edition of the quarterly Information InDepth EPPM Newsletter

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• Silverlight Cream for November 20, 2011 - 2 -- #1170

  - by Dave Campbell

  In this Issue: Michael Washington, Oliver Fuh, Jeremy Likness, Derik Whittaker, Jesse Liberty, Jeff Blankenburg(-2-), and Michael Crump. Above the Fold: Silverlight: "Handling Extremely Large Data Sets in Silverlight" Jeremy Likness WP7: "31 Days of Mango | Day #8: Contacts API" Jeff Blankenburg LightSwitch: "LightSwitch Chat Application Using A Data Source Extension" Michael Washington Shoutouts: Michael Palermo's latest Desert Mountain Developers is up Michael Washington's latest Visual Studio #LightSwitch Daily is up Check out Shawn Wildermuth's take on the AppStore and WP7 in general: 40,000 Apps - What Does It Mean? Be sure to check out Jesse Liberty & Paul Betts new book: Programming Reactive Extensions and LINQ, I've just had a little time to look at mine, but don't let the size fool you... this is the good stuff! From SilverlightCream.com: LightSwitch Chat Application Using A Data Source Extension In his latest LightSwitch post, Michael Washington gives up code that will enable two people using the same LightSwitch app to chat. Great detailed tutorial as usual! Handling AdControl Fetching Exception WindowsPhoneGeek turns the blog reigns over to Oliver Fuh for this post about using the AdControl in your WP7 app and handling a common exception you get with the Microsoft AdControl Handling Extremely Large Data Sets in Silverlight In this excerpt from his book, Jeremy Likness discusses reading *LARGE* data sets with Silverlight using 3 different patterns: OData, WCF RIA Services, and MVVM. Using MVVM with the AutoCompleteTextBox in Silverlight 4 Derik Whittaker takes a break from WinRT to discuss the Silverlight 4 AutoCompleteTextBox and MVVM ... including a custom Behavior to allow the backing property to be updated and a command to trigger background searches Yet Another Podcast #52–Peter Torr on Windows Phone Multitasking Jesse Liberty scored Peter Torr on his Latest Yet Another Podcast .. talking about Multitasking on Windows Phone including background agents, the backstack, and other Mango features 31 Days of Mango | Day #8: Contacts API Jeff Blankenburg's Day 8 is about a new namespace on WP7: Microsoft.Phone.UserData ... now giving us the ability to treat the user's contact list like a local database 31 Days of Mango | Day #9: Calendar API On Day 9 in his series, Jeff Blankenburg revisits the Microsoft.Phone.UserData namespace and looks at another set of data: the calendar Want to Decompile Silverlight XAP files? Try JustDecompile Beta! Michael Crump has a post up about the new free developer productivity tool from Telerik that provides assembly browsing and decompiling: JustDecompile ... Just download it! Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• How to Code Faster (Without Sacrificing Quality)

  - by ashes999

  I've been a professional coder for a several years. The comments about my code have generally been the same: writes great code, well-tested, but could be faster. So how do I become a faster coder, without sacrificing quality? For the sake of this question, I'm going to limit the scope to C#, since that's primarily what I code (for fun) -- or Java, which is similar enough in many ways that matter. Things that I'm already doing: Write the minimal solution that will get the job done Write a slew of automated tests (prevents regressions) Write (and use) reusable libraries for all kinds of things Use well-known technologies where they work well (eg. Hibernate) Use design patterns where they fit into place (eg. Singleton) These are all great, but I don't feel like my speed is increasing over time. I do care, because if I can do something to increase my productivity (even by 10%), that's 10% faster than my competitors. (Not that I have any.) Besides which, I've consistently gotten this feeback from my managers -- whether it was small-scale Flash development or enterprise Java/C++ development. Edit: There seem to be a lot of questions about what I mean by fast, and how I know I'm slow. Let me clarify with some more details. I worked in small and medium-sized teams (5-50 people) in various companies over various projects and various technologies (Flash, ASP.NET, Java, C++). The observation of my managers (which they told me directly) is that I'm "slow." Part of this is because a significant number of my peers sacrificed quality for speed; they wrote code that was buggy, hard to read, hard to maintain, and difficult to write automated tests for. My code generally is well-documented, readable, and testable. At Oracle, I would consistently solve bugs slower than other team-members. I know this, because I would get comments to that effect; this means that other (yes, more senior and experienced) developers could do my work in less time than it took me, at nearly the same quality (readability, maintainability, and testability). Why? What am I missing? How can I get better at this? My end goal is simple: if I can make product X in 40 hours today, and I can improve myself somehow so that I can create the same product at 20, 30, or even 38 hours tomorrow, that's what I want to know -- how do I get there? What process can I use to continually improve? I had thought it was about reusing code, but that's not enough, it seems.

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• Going for Gold

  - by Simple-Talk Editorial Team

  There was a spring in the step of some members of our development teams here at Red Gate, on hearing that on five gold awards at 2012′s SQL Mag Community and Editors Choice Awards. And why not? It’s a nice recognition that their efforts were appreciated by many in the SQL Server community. The team at Simple-Talk don’t tend to spring, but even we felt a twinge of pride in the fact that SQL Scripts Manager received Gold for Editor’s Choice in the Best Free Tools category. The tool began life as a “Down Tools” project and is one that we’ve supported and championed in various articles on Simple-talk.com. Over a Cambridge Bitter in the Waggon and Horses, we’ve often reflected on how nice it would be to nominate our own awards. Of course, we’d have to avoid nominating Red Gate tools in each category, even the free ones, for fear of seeming biased,  but we could still award other people’s free tools, couldn’t we? So allow us to set the stage for the annual Simple-Talk Community Tool awards… Onto the platform we shuffle, to applause from the audience; Chris in immaculate tuxedo, Alice in stunning evening gown, Dave and Tony looking vaguely uncomfortable, Andrew somehow distracted, as if his mind is elsewhere. Tony strides up to the lectern, and coughs lightly…”In the free-tool category we have the three nominations, and they are…” (rustle of the envelope opening) Ola Hallengren’s SQL Server Maintenance Solution (applause) Adam Machanic’s WhoIsActive (cheers, more applause) Brent Ozar’s sp_Blitz (much clapping) “Before we declare the winner, I’d like to say a few words in recognition of a grand tradition in a SQL Server community that continues to offer its members a steady supply of excellent, free tools. It hammers home the fundamental principle that a tool should solve a single, pressing and frustrating problem, but you should only ever build your own solution to that problem if you are certain that you cannot buy it, or that someone has not already provided it free. We have only three finalists tonight, but I feel compelled to mention a few other tools that we also use and appreciate, such as Microsoft’s Logparser, Open source Curl, Microsoft’s TableDiff.exe, Performance Analysis of Logs (PAL) Tool, SQL Server Cache Manager and SQLPSX.” “And now I’ll hand over to Alice to announce the winner.” Alice strides over to the microphone, tearing open the envelope. “The winner,” she pauses for dramatic effect “… is …Ola Hallengren’s SQL Server Maintenance Solution!” Queue much applause and consumption of champagne. Did we get it wrong? What free tool would you nominate? Let us know! Cheers, Simple-Talk Editorial Team (Andrew, Alice, Chris, Dave, Tony)

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• MAXDOP in SQL Azure

  - by Herve Roggero

  In my search of better understanding the scalability options of SQL Azure I stumbled on an interesting aspect: Query Hints in SQL Azure. More specifically, the MAXDOP hint. A few years ago I did a lot of analysis on this query hint (see article on SQL Server Central:  http://www.sqlservercentral.com/articles/Configuring/managingmaxdegreeofparallelism/1029/).  Here is a quick synopsis of MAXDOP: It is a query hint you use when issuing a SQL statement that provides you control with how many processors SQL Server will use to execute the query. For complex queries with lots of I/O requirements, more CPUs can mean faster parallel searches. However the impact can be drastic on other running threads/processes. If your query takes all available processors at 100% for 5 minutes... guess what... nothing else works. The bottom line is that more is not always better. The use of MAXDOP is more art than science... and a whole lot of testing; it depends on two things: the underlying hardware architecture and the application design. So there isn't a magic number that will work for everyone... except 1... :) Let me explain. The rules of engagements are different. SQL Azure is about sharing. Yep... you are forced to nice with your neighbors.  To achieve this goal SQL Azure sets the MAXDOP to 1 by default, and ignores the use of the MAXDOP hint altogether. That means that all you queries will use one and only one processor.  It really isn't such a bad thing however. Keep in mind that in some of the largest SQL Server implementations MAXDOP is usually also set to 1. It is a well known configuration setting for large scale implementations. The reason is precisely to prevent rogue statements (like a SELECT * FROM HISTORY) from bringing down your systems (like a report that should have been running on a different in the first place) and to avoid the overhead generated by executing too many parallel queries that could cause internal memory management nightmares to the host Operating System. Is summary, forcing the MAXDOP to 1 in SQL Azure makes sense; it ensures that your database will continue to function normally even if one of the other tenants on the same server is running massive queries that would otherwise bring you down. Last but not least, keep in mind as well that when you test your database code for performance on-premise, make sure to set the DOP to 1 on your SQL Server databases to simulate SQL Azure conditions.

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• Java Space on Parleys

  - by Yolande Poirier

  Now available! A great selection of JavaOne 2010 and JVM Language Summit 2010 sessions as well as Oracle Technology Network TechCasts on the new Java Space on Parleys website. Oracle partnered with Stephan Janssen, founder of Parleys to make this happen. Parleys website offers a user friendly experience to view online content. You can download some of the talks to your desktop or watch them on the go on mobile devices. The current selection is a well of expertise from top Java luminaries and Oracle experts. JavaOne 2010 sessions: ·        Best practices for signing code by Sean Mullan   ·        Building software using rich client platforms by Rickard Thulin ·        Developing beyond the component libraries by Ryan Cuprak ·        Java API for keyhole markup language by Florian Bachmann ·        Avoiding common user experience anti-patterns by Burk Hufnagel ·        Accelerating Java workloads via GPUs by Gary Frost JVM Languages Summit 2010 sessions: ·      Mixed language project compilation in Eclipse by Andy Clement  ·      Gathering the threads by John Rose  ·      LINQ: language features for concurrency by Neal Gafter  ·      Improvements in OpenJDK useful for JVM languages by Eric Caspole  ·      Symmetric Multilanguage - VM Architecture by Oleg Pliss  Special interviews with Oracle experts on product innovations: ·      Ludovic Champenois, Java EE architect on Glassfish 3.1 and Java EE. ·      John Jullion-Ceccarelli and Martin Ryzl on NetBeans IDE 6.9 You can chose to listen to a section of talks using the agenda view and search for related content while watching a presentation.  Enjoy the Java content and vote on it! 

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