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• Table Variables: an empirical approach.

  - by Phil Factor

  It isn’t entirely a pleasant experience to publish an article only to have it described on Twitter as ‘Horrible’, and to have it criticized on the MVP forum. When this happened to me in the aftermath of publishing my article on Temporary tables recently, I was taken aback, because these critics were experts whose views I respect. What was my crime? It was, I think, to suggest that, despite the obvious quirks, it was best to use Table Variables as a first choice, and to use local Temporary Tables if you hit problems due to these quirks, or if you were doing complex joins using a large number of rows. What are these quirks? Well, table variables have advantages if they are used sensibly, but this requires some awareness by the developer about the potential hazards and how to avoid them. You can be hit by a badly-performing join involving a table variable. Table Variables are a compromise, and this compromise doesn’t always work out well. Explicit indexes aren’t allowed on Table Variables, so one cannot use covering indexes or non-unique indexes. The query optimizer has to make assumptions about the data rather than using column distribution statistics when a table variable is involved in a join, because there aren’t any column-based distribution statistics on a table variable. It assumes a reasonably even distribution of data, and is likely to have little idea of the number of rows in the table variables that are involved in queries. However complex the heuristics that are used might be in determining the best way of executing a SQL query, and they most certainly are, the Query Optimizer is likely to fail occasionally with table variables, under certain circumstances, and produce a Query Execution Plan that is frightful. The experienced developer or DBA will be on the lookout for this sort of problem. In this blog, I’ll be expanding on some of the tests I used when writing my article to illustrate the quirks, and include a subsequent example supplied by Kevin Boles. A simplified example. We’ll start out by illustrating a simple example that shows some of these characteristics. We’ll create two tables filled with random numbers and then see how many matches we get between the two tables. We’ll forget indexes altogether for this example, and use heaps. We’ll try the same Join with two table variables, two table variables with OPTION (RECOMPILE) in the JOIN clause, and with two temporary tables. It is all a bit jerky because of the granularity of the timing that isn’t actually happening at the millisecond level (I used DATETIME). However, you’ll see that the table variable is outperforming the local temporary table up to 10,000 rows. Actually, even without a use of the OPTION (RECOMPILE) hint, it is doing well. What happens when your table size increases? The table variable is, from around 30,000 rows, locked into a very bad execution plan unless you use OPTION (RECOMPILE) to provide the Query Analyser with a decent estimation of the size of the table. However, if it has the OPTION (RECOMPILE), then it is smokin’. Well, up to 120,000 rows, at least. It is performing better than a Temporary table, and in a good linear fashion. What about mixed table joins, where you are joining a temporary table to a table variable? You’d probably expect that the query analyzer would throw up its hands and produce a bad execution plan as if it were a table variable. After all, it knows nothing about the statistics in one of the tables so how could it do any better? Well, it behaves as if it were doing a recompile. And an explicit recompile adds no value at all. (we just go up to 45000 rows since we know the bigger picture now)   Now, if you were new to this, you might be tempted to start drawing conclusions. Beware! We’re dealing with a very complex beast: the Query Optimizer. It can come up with surprises What if we change the query very slightly to insert the results into a Table Variable? We change nothing else and just measure the execution time of the statement as before. Suddenly, the table variable isn’t looking so much better, even taking into account the time involved in doing the table insert. OK, if you haven’t used OPTION (RECOMPILE) then you’re toast. Otherwise, there isn’t much in it between the Table variable and the temporary table. The table variable is faster up to 8000 rows and then not much in it up to 100,000 rows. Past the 8000 row mark, we’ve lost the advantage of the table variable’s speed. Any general rule you may be formulating has just gone for a walk. What we can conclude from this experiment is that if you join two table variables, and can’t use constraints, you’re going to need that Option (RECOMPILE) hint. Count Dracula and the Horror Join. These tables of integers provide a rather unreal example, so let’s try a rather different example, and get stuck into some implicit indexing, by using constraints. What unusual words are contained in the book ‘Dracula’ by Bram Stoker? Here we get a table of all the common words in the English language (60,387 of them) and put them in a table. We put them in a Table Variable with the word as a primary key, a Table Variable Heap and a Table Variable with a primary key. We then take all the distinct words used in the book ‘Dracula’ (7,558 of them). We then create a table variable and insert into it all those uncommon words that are in ‘Dracula’. i.e. all the words in Dracula that aren’t matched in the list of common words. To do this we use a left outer join, where the right-hand value is null. The results show a huge variation, between the sublime and the gorblimey. If both tables contain a Primary Key on the columns we join on, and both are Table Variables, it took 33 Ms. If one table contains a Primary Key, and the other is a heap, and both are Table Variables, it took 46 Ms. If both Table Variables use a unique constraint, then the query takes 36 Ms. If neither table contains a Primary Key and both are Table Variables, it took 116383 Ms. Yes, nearly two minutes!! If both tables contain a Primary Key, one is a Table Variables and the other is a temporary table, it took 113 Ms. If one table contains a Primary Key, and both are Temporary Tables, it took 56 Ms.If both tables are temporary tables and both have primary keys, it took 46 Ms. Here we see table variables which are joined on their primary key again enjoying a  slight performance advantage over temporary tables. Where both tables are table variables and both are heaps, the query suddenly takes nearly two minutes! So what if you have two heaps and you use option Recompile? If you take the rogue query and add the hint, then suddenly, the query drops its time down to 76 Ms. If you add unique indexes, then you've done even better, down to half that time. Here are the text execution plans.So where have we got to? Without drilling down into the minutiae of the execution plans we can begin to create a hypothesis. If you are using table variables, and your tables are relatively small, they are faster than temporary tables, but as the number of rows increases you need to do one of two things: either you need to have a primary key on the column you are using to join on, or else you need to use option (RECOMPILE) If you try to execute a query that is a join, and both tables are table variable heaps, you are asking for trouble, well- slow queries, unless you give the table hint once the number of rows has risen past a point (30,000 in our first example, but this varies considerably according to context). Kevin’s Skew In describing the table-size, I used the term ‘relatively small’. Kevin Boles produced an interesting case where a single-row table variable produces a very poor execution plan when joined to a very, very skewed table. In the original, pasted into my article as a comment, a column consisted of 100000 rows in which the key column was one number (1) . To this was added eight rows with sequential numbers up to 9. When this was joined to a single-tow Table Variable with a key of 2 it produced a bad plan. This problem is unlikely to occur in real usage, and the Query Optimiser team probably never set up a test for it. Actually, the skew can be slightly less extreme than Kevin made it. The following test showed that once the table had 54 sequential rows in the table, then it adopted exactly the same execution plan as for the temporary table and then all was well. Undeniably, real data does occasionally cause problems to the performance of joins in Table Variables due to the extreme skew of the distribution. We've all experienced Perfectly Poisonous Table Variables in real live data. As in Kevin’s example, indexes merely make matters worse, and the OPTION (RECOMPILE) trick does nothing to help. In this case, there is no option but to use a temporary table. However, one has to note that once the slight de-skew had taken place, then the plans were identical across a huge range. Conclusions Where you need to hold intermediate results as part of a process, Table Variables offer a good alternative to temporary tables when used wisely. They can perform faster than a temporary table when the number of rows is not great. For some processing with huge tables, they can perform well when only a clustered index is required, and when the nature of the processing makes an index seek very effective. Table Variables are scoped to the batch or procedure and are unlikely to hang about in the TempDB when they are no longer required. They require no explicit cleanup. Where the number of rows in the table is moderate, you can even use them in joins as ‘Heaps’, unindexed. Beware, however, since, as the number of rows increase, joins on Table Variable heaps can easily become saddled by very poor execution plans, and this must be cured either by adding constraints (UNIQUE or PRIMARY KEY) or by adding the OPTION (RECOMPILE) hint if this is impossible. Occasionally, the way that the data is distributed prevents the efficient use of Table Variables, and this will require using a temporary table instead. Tables Variables require some awareness by the developer about the potential hazards and how to avoid them. If you are not prepared to do any performance monitoring of your code or fine-tuning, and just want to pummel out stuff that ‘just runs’ without considering namby-pamby stuff such as indexes, then stick to Temporary tables. If you are likely to slosh about large numbers of rows in temporary tables without considering the niceties of processing just what is required and no more, then temporary tables provide a safer and less fragile means-to-an-end for you.

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• Code Reuse is (Damn) Hard

  - by James Michael Hare

  Being a development team lead, the task of interviewing new candidates was part of my job.  Like any typical interview, we started with some easy questions to get them warmed up and help calm their nerves before hitting the hard stuff. One of those easier questions was almost always: “Name some benefits of object-oriented development.”  Nearly every time, the candidate would chime in with a plethora of canned answers which typically included: “it helps ease code reuse.”  Of course, this is a gross oversimplification.  Tools only ease reuse, its developers that ultimately can cause code to be reusable or not, regardless of the language or methodology. But it did get me thinking…  we always used to say that as part of our mantra as to why Object-Oriented Programming was so great.  With polymorphism, inheritance, encapsulation, etc. we in essence set up the concepts to help facilitate reuse as much as possible.  And yes, as a developer now of many years, I unquestionably held that belief for ages before it really struck me how my views on reuse have jaded over the years.  In fact, in many ways Agile rightly eschews reuse as taking a backseat to developing what's needed for the here and now.  It used to be I was in complete opposition to that view, but more and more I've come to see the logic in it.  Too many times I've seen developers (myself included) get lost in design paralysis trying to come up with the perfect abstraction that would stand all time.  Nearly without fail, all of these pieces of code become obsolete in a matter of months or years. It’s not that I don’t like reuse – it’s just that reuse is hard.  In fact, reuse is DAMN hard.  Many times it is just a distraction that eats up architect and developer time, and worse yet can be counter-productive and force wrong decisions.  Now don’t get me wrong, I love the idea of reusable code when it makes sense.  These are in the few cases where you are designing something that is inherently reusable.  The problem is, most business-class code is inherently unfit for reuse! Furthermore, the code that is reusable will often fail to be reused if you don’t have the proper framework in place for effective reuse that includes standardized versioning, building, releasing, and documenting the components.  That should always be standard across the board when promoting reusable code.  All of this is hard, and it should only be done when you have code that is truly reusable or you will be exerting a large amount of development effort for very little bang for your buck. But my goal here is not to get into how to reuse (that is a topic unto itself) but what should be reused.  First, let’s look at an extension method.  There’s many times where I want to kick off a thread to handle a task, then when I want to reign that thread in of course I want to do a Join on it.  But what if I only want to wait a limited amount of time and then Abort?  Well, I could of course write that logic out by hand each time, but it seemed like a great extension method: 1: public static class ThreadExtensions 2: { 3: public static bool JoinOrAbort(this Thread thread, TimeSpan timeToWait) 4: { 5: bool isJoined = false; 6:  7: if (thread != null) 8: { 9: isJoined = thread.Join(timeToWait); 10:  11: if (!isJoined) 12: { 13: thread.Abort(); 14: } 15: } 16: return isJoined; 17: } 18: } 19:  When I look at this code, I can immediately see things that jump out at me as reasons why this code is very reusable.  Some of them are standard OO principles, and some are kind-of home grown litmus tests: Single Responsibility Principle (SRP) – The only reason this extension method need change is if the Thread class itself changes (one responsibility). Stable Dependencies Principle (SDP) – This method only depends on classes that are more stable than it is (System.Threading.Thread), and in itself is very stable, hence other classes may safely depend on it. It is also not dependent on any business domain, and thus isn't subject to changes as the business itself changes. Open-Closed Principle (OCP) – This class is inherently closed to change. Small and Stable Problem Domain – This method only cares about System.Threading.Thread. All-or-None Usage – A user of a reusable class should want the functionality of that class, not parts of that functionality.  That’s not to say they most use every method, but they shouldn’t be using a method just to get half of its result. Cost of Reuse vs. Cost to Recreate – since this class is highly stable and minimally complex, we can offer it up for reuse very cheaply by promoting it as “ready-to-go” and already unit tested (important!) and available through a standard release cycle (very important!). Okay, all seems good there, now lets look at an entity and DAO.  I don’t know about you all, but there have been times I’ve been in organizations that get the grand idea that all DAOs and entities should be standardized and shared.  While this may work for small or static organizations, it’s near ludicrous for anything large or volatile. 1: namespace Shared.Entities 2: { 3: public class Account 4: { 5: public int Id { get; set; } 6:  7: public string Name { get; set; } 8:  9: public Address HomeAddress { get; set; } 10:  11: public int Age { get; set;} 12:  13: public DateTime LastUsed { get; set; } 14:  15: // etc, etc, etc... 16: } 17: } 18:  19: ... 20:  21: namespace Shared.DataAccess 22: { 23: public class AccountDao 24: { 25: public Account FindAccount(int id) 26: { 27: // dao logic to query and return account 28: } 29:  30: ... 31:  32: } 33: } Now to be fair, I’m not saying there doesn’t exist an organization where some entites may be extremely static and unchanging.  But at best such entities and DAOs will be problematic cases of reuse.  Let’s examine those same tests: Single Responsibility Principle (SRP) – The reasons to change for these classes will be strongly dependent on what the definition of the account is which can change over time and may have multiple influences depending on the number of systems an account can cover. Stable Dependencies Principle (SDP) – This method depends on the data model beneath itself which also is largely dependent on the business definition of an account which can be very inherently unstable. Open-Closed Principle (OCP) – This class is not really closed for modification.  Every time the account definition may change, you’d need to modify this class. Small and Stable Problem Domain – The definition of an account is inherently unstable and in fact may be very large.  What if you are designing a system that aggregates account information from several sources? All-or-None Usage – What if your view of the account encompasses data from 3 different sources but you only care about one of those sources or one piece of data?  Should you have to take the hit of looking up all the other data?  On the other hand, should you have ten different methods returning portions of data in chunks people tend to ask for?  Neither is really a great solution. Cost of Reuse vs. Cost to Recreate – DAOs are really trivial to rewrite, and unless your definition of an account is EXTREMELY stable, the cost to promote, support, and release a reusable account entity and DAO are usually far higher than the cost to recreate as needed. It’s no accident that my case for reuse was a utility class and my case for non-reuse was an entity/DAO.  In general, the smaller and more stable an abstraction is, the higher its level of reuse.  When I became the lead of the Shared Components Committee at my workplace, one of the original goals we looked at satisfying was to find (or create), version, release, and promote a shared library of common utility classes, frameworks, and data access objects.  Now, of course, many of you will point to nHibernate and Entity for the latter, but we were looking at larger, macro collections of data that span multiple data sources of varying types (databases, web services, etc). As we got deeper and deeper in the details of how to manage and release these items, it quickly became apparent that while the case for reuse was typically a slam dunk for utilities and frameworks, the data access objects just didn’t “smell” right.  We ended up having session after session of design meetings to try and find the right way to share these data access components. When someone asked me why it was taking so long to iron out the shared entities, my response was quite simple, “Reuse is hard...”  And that’s when I realized, that while reuse is an awesome goal and we should strive to make code maintainable, often times you end up creating far more work for yourself than necessary by trying to force code to be reusable that inherently isn’t. Think about classes the times you’ve worked in a company where in the design session people fight over the best way to implement a class to make it maximally reusable, extensible, and any other buzzwordable.  Then think about how quickly that design became obsolete.  Many times I set out to do a project and think, “yes, this is the best design, I can extend it easily!” only to find out the business requirements change COMPLETELY in such a way that the design is rendered invalid.  Code, in general, tends to rust and age over time.  As such, writing reusable code can often be difficult and many times ends up being a futile exercise and worse yet, sometimes makes the code harder to maintain because it obfuscates the design in the name of extensibility or reusability. So what do I think are reusable components? Generic Utility classes – these tend to be small classes that assist in a task and have no business context whatsoever. Implementation Abstraction Frameworks – home-grown frameworks that try to isolate changes to third party products you may be depending on (like writing a messaging abstraction layer for publishing/subscribing that is independent of whether you use JMS, MSMQ, etc). Simplification and Uniformity Frameworks – To some extent this is similar to an abstraction framework, but there may be one chosen provider but a development shop mandate to perform certain complex items in a certain way.  Or, perhaps to simplify and dumb-down a complex task for the average developer (such as implementing a particular development-shop’s method of encryption). And what are less reusable? Application and Business Layers – tend to fluctuate a lot as requirements change and new features are added, so tend to be an unstable dependency.  May be reused across applications but also very volatile. Entities and Data Access Layers – these tend to be tuned to the scope of the application, so reusing them can be hard unless the abstract is very stable. So what’s the big lesson?  Reuse is hard.  In fact it’s damn hard.  And much of the time I’m not convinced we should focus too hard on it. If you’re designing a utility or framework, then by all means design it for reuse.  But you most also really set down a good versioning, release, and documentation process to maximize your chances.  For anything else, design it to be maintainable and extendable, but don’t waste the effort on reusability for something that most likely will be obsolete in a year or two anyway.

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• CodePlex Daily Summary for Monday, October 24, 2011

  CodePlex Daily Summary for Monday, October 24, 2011Popular ReleasesPeople's Note: People's Note 0.31: Added note tag editing. Changed note edit conflict resolution to keep the latest version. To install: copy the appropriate CAB file onto your WM device and run it.Windows Azure Toolkit for Windows Phone: Windows Azure Toolkit for Windows Phone v1.3.1: Upgraded Windows Azure projects to Windows Azure Tools for Microsoft Visual Studio 2010 1.5 – September 2011 Upgraded the tools tools to support the Windows Phone Developer Tools RTW Update SQL Azure only scenarios to use ASP.NET Universal Providers (through the System.Web.Providers v1.0.1 NuGet package) Changed Shared Access Signature service interface to support more operations Refactored Blobs API to have a similar interface and usage to that provided by the Windows Azure SDK Stor...Workflow Automation (for Dynamics CRM 2011): Release 1.0: Initial release version 1.0.Window Manipulation with the Microsoft Touch Mouse: Window Touch v1.0: This is the initial release of the Window Touch software, which may have bugs and incomplete interactions. Please be patient with us as we work out all of the kinks, and feel free to send comments. To install and run the program download and double click the .msi file below. Make sure you already have a Microsoft Touch Mouse and can use it before installing.xUnit.net Contrib: xunitcontrib-resharper 0.4.4 (dotCover): xunitcontrib release 0.4.4 (ReSharper runner) This release provides a test runner plugin for Resharper 6.0 RTM, targetting all versions of xUnit.net. (See the xUnit.net project to download xUnit.net itself.) This release addresses the following issues:Support for dotCover code coverage 4132 Note that this build work against ALL VERSIONS of xunit. The files are compiled against xunit.dll 1.8 - DO NOT REPLACE THIS FILE. Thanks to xunit's version independent runner system, this package can r...BookShop: BookShop: BookShop WP7 clientRibbon Editor for Microsoft Dynamics CRM 2011: Ribbon Editor (0.1.2122.266): Added CodePlex and PayPal links New icon Bug fix: can't connect to an IFD deployment when the discovery service url has been customizedSiteMap Editor for Microsoft Dynamics CRM 2011: SiteMap Editor (1.0.921.340): Added CodePlex and PayPal links New iconMVCQuick: MVCQuick 0.3.1: Features??NHibernate 3.2??Repository（ORuM） ??Spring.Net 1.3.2??Container（IoC） ??Common.Logging 1.2??Logging ASP.NET Security Provider?? ??MVCQuick.Framework??MusicStoreDotNet.Framework.Common: DotNet.Framework.Common 4.0: ??????????，????????????XML Explorer: XML Explorer 4.0.5: Changes in 4.0.5: Added 'Copy Attribute XPath to Address Bar' feature. Added methods for decoding node text and value from Base64 encoded strings, and copying them to the clipboard. Added 'ChildNodeDefinitions' to the options, which allows for easier navigation of parent-child and ID-IDREF relationships. Discovery happens on-demand, as nodes are expanded and child nodes are added. Nodes can now have 'virtual' child nodes, defined by an xpath to select an identifier (usually relative to ...Media Companion: MC 3.419b Weekly: A couple of minor bug fixes, but the important fix in this release is to tackle the extremely long load times for users with large TV collections (issue #130). A note has been provided by developer Playos: "One final note, you will have to suffer one final long load and then it should be fixed... alternatively you can delete the TvCache.xml and rebuild your library... The fix was to include the file extension so it doesn't have to look for the video file (checking to see if a file exists is a...CODE Framework: 4.0.11021.0: This build adds a lot of our WPF components, including our MVVC and MVC components as well as a "Metro" and "Battleship" style.GridLibre para Visual FoxPro: GridLibre para Visual FoxPro v3.5: GridLibre Para Visual FoxPro: esta herramienta ayudara a los usuarios y programadores en los manejos de los datos, como Filtrar, multiseleccion y el autoformato a las columnas como la asignacion del controlsource.Umbraco CMS: Umbraco 5.0 CMS Alpha 3: Umbraco 5 Alpha 3Umbraco 5 (aka Jupiter) will be the next version of everyone's favourite, friendly ASP.NET CMS that already powers over 100,000 websites worldwide. Try out the Alpha of v5 today! If you're new to Umbraco and would like to get a low-down on our popular and easy-to-learn approach to content management, check out our intro video. What's Alpha 3?This is our third Alpha release. It's intended for developers looking to become familiar with the codebase & architecture, or for thos...Vkontakte WP: Vkontakte: source codeWay2Sms Applications for Android, Desktop/Laptop & Java enabled phones: Way2SMS Desktop App v2.0: 1. Fixed issue with sending messages due to changes to Way2Sms site 2. Updated the character limit to 160 from 140GART - Geo Augmented Reality Toolkit: 1.0.1: About Release 1.0.1 Release 1.0.1 is a service release that addresses several issues and improves performance. As always, check the Documentation tab for instructions on how to get started. If you don't have the Windows Phone SDK yet, grab it here. Breaking Change Please note: There is a breaking change in this release. As noted below, the WorldCalculationMode property of ARItem has been replaced by a user-definable function. ARItem is now automatically wired up with a function that perform...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.32: Fix for issue #16710 - string literals in "constant literal operations" which contain ASP.NET substitutions should not be considered "constant." Move the JS1284 error (Misplaced Function Declaration) so it only fires when in strict mode. I got a couple complaints that people didn't like that error popping up in their existing code when they could verify that the location of that function, although not strict JS, still functions as expected cross-browser.Naked Objects: Naked Objects Release 4.0.110.0: Corresponds to the packaged version 4.0.110.0 available via NuGet. Please note that the easiest way to install and run the Naked Objects Framework is via the NuGet package manager: just search the Official NuGet Package Source for 'nakedobjects'. It is only necessary to download the source code (from here) if you wish to modify or re-build the framework yourself. If you do wish to re-build the framework, consul the file HowToBuild.txt in the release. Documentation Please note that after ...New Projects360zebra4en: 360zebra???AG: Web Framework that can leverage silverlight, but fall back on native html if silverlight is not available.BookShop: BookShop ????? ???? ? ????????????? ?????????.CompendiumImport: Import data from Dungeons & Dragons Compendium to Masterplan librariesCS 6235 Arbiter Server: CS 6235 Arbiter ServerDual numbers for automatic differentiation: Dual numbers can be used to automatically calculate numerically stable derivatives of functions.Effort - Entity Framework Unit Testing Tool: Effort is a powerful unit testing tool that brings an easy way to create unit tests for Entity Framework based applications. It can manipulate the behavior of EntityConnection or ObjectContext objects, so that the data operations are executed by a fake in-process database, while omitting the real database completely. This mechanism makes possible to remove the dependency between your unit test and the real database.FlexiCache for ASP.NET applications: This library provides extended cache capabilities to the ASP.NET applications. It includes the MongoDB and SQL Server output cache providers extending ASP.NET Output Cache capabilities by allowing to store cached data outside of the application process that is especially important in web-farm scenario. This library provides "Session-On-Demand" functionality - ability to separate ASP.NET Session data to subsets that can be stored outside of the main ASP.NET session and loaded on demand w...HtmlAgilityPackContrib - Logical extension to HtmlAgilityPack: HtmlAgilityPackContrib - A logical extension to HtmlAgilityPack to parse HTML using jQuery like methods inspired by jSoupjsonhttphandler: The JsonHttpHandler is a simple JSON oriented Http handler to easily integrate JSON GET, POST, and JSONP web services into your application.My Recent Documents: This Webpart for Sharepoint 2010 is developed for users that need help finding the last number of documents they have been working on. The target user have trouble location where he/she placed their documents. This Webpart gives the following features... 1. Locate your last edited documents.. 2. Customize how many documents the webpart should find. 3. Should it look in subsites also? 4. Show the structure in where the documents are located and click easy link to either document lib...Option pricing for arbitrary distributions: European option pricing with arbitrary distributions using dual numbers to calculate greeks.Project Tracy: ????????？ ????????？ ????????10??????？ ???????????????????????。。。。。 ???！Tracy?????????????！（?RegSharp: RegSharp provides server functionality for Sencha Extjs (http://www.sencha.com/products/extjs/) paging grid. RegSharp implements sorting, filtering and paging logic on the server side that is required for using the paging grid. Is't developed in C#SharePoint/TFS Continuous Integration Starter Pack: Provides a customized TFS Build workflow and PowerShell scripts to get started with Continuous Integration (automated builds) in SharePoint 2010/TFS 2010. This pack will allow you to automatically build and deploy WSPs using TFS, and optionally also include automated testing as part of the build such as Visual Studio 2010's Coded UI Tests. Sharp Investor: Sharp Investor pools various online sources as well as preforms a couple local calculation to return recommended stocks. The program is easy to use, and requires very little work to find profitable stocks online. It's developed in C#.SharpXML: Aims to be a simpler library for interacting with XML files that exposes attributes and children elements as properties and objects respectively.Splash: Splash is an interactive MediaCenter-style YouTube client written in WPF.TomCdc: TomCdc is a solution which makes tracking of sql databse changes easy. Quick and simple installation process allows to start using the solution in just a few minutes. It supports all versions of Microsoft Sql server. You'll no longer have to write triggers manually to find out what process is changing data in a table.Track your work: Another work-time tracker TumblePower: TumblePower is a simplified API library for Tumblr. Use it in your application to post Text, Photos, Quotes, Links, Chats, Audio and Videos as well as set functions such as tags, dates and choose whether the post should be private or not.VisualBASH: This project aims to extends Visual Studio's language support to include bash scripting. This includes syntax highlighting, code completion, and syntax error checking.Window Manipulation with the Microsoft Touch Mouse: Window Manipulation for the Microsoft Touch Mouse provides a set of simple gestures for moving and resizing windows.Workflow Automation (for Dynamics CRM 2011): Workflow Automation for Dynamics CRM 2011 allows user to automate or schedule workflow execution via Windows Task Scheduler. XNA Model Viewer: The XNA Model Viewer allows you to load FBX files and view them. It allows you to test that models will work in XNA, determine the effect of modifying bone transforms, and view animation clips. You can examine the bones and meshes and see the complete hierarchy.

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• Which programming idiom to choose for this open source library?

  - by Walkman

  I have an interesting question about which programming idiom is easier to use for beginner developers writing concrete file parsing classes. I'm developing an open source library, which one of the main functionality is to parse plain text files and get structured information from them. All of the files contains the same kind of information, but can be in different formats like XML, plain text (each of them is structured differently), etc. There are a common set of information pieces which is the same in all (e.g. player names, table names, some id numbers) There are formats which are very similar to each other, so it's possible to define a common Base class for them to facilitate concrete format parser implementations. So I can clearly define base classes like SplittablePlainTextFormat, XMLFormat, SeparateSummaryFormat, etc. Each of them hints the kind of structure they aim to parse. All of the concrete classes should have the same information pieces, no matter what. To be useful at all, this library needs to define at least 30-40 of these parsers. A couple of them are more important than others (obviously the more popular formats). Now my question is, which is the best programming idiom to choose to facilitate the development of these concrete classes? Let me explain: I think imperative programming is easy to follow even for beginners, because the flow is fixed, the statements just come one after another. Right now, I have this: class SplittableBaseFormat: def parse(self): "Parses the body of the hand history, but first parse header if not yet parsed." if not self.header_parsed: self.parse_header() self._parse_table() self._parse_players() self._parse_button() self._parse_hero() self._parse_preflop() self._parse_street('flop') self._parse_street('turn') self._parse_street('river') self._parse_showdown() self._parse_pot() self._parse_board() self._parse_winners() self._parse_extra() self.parsed = True So the concrete parser need to define these methods in order in any way they want. Easy to follow, but takes longer to implement each individual concrete parser. So what about declarative? In this case Base classes (like SplittableFormat and XMLFormat) would do the heavy lifting based on regex and line/node number declarations in the concrete class, and concrete classes have no code at all, just line numbers and regexes, maybe other kind of rules. Like this: class SplittableFormat: def parse_table(): "Parses TABLE_REGEX and get information" # set attributes here def parse_players(): "parses PLAYER_REGEX and get information" # set attributes here class SpecificFormat1(SplittableFormat): TABLE_REGEX = re.compile('^(?P<table_name>.*) other info \d* etc') TABLE_LINE = 1 PLAYER_REGEX = re.compile('^Player \d: (?P<player_name>.*) has (.*) in chips.') PLAYER_LINE = 16 class SpecificFormat2(SplittableFormat): TABLE_REGEX = re.compile(r'^Tournament #(\d*) (?P<table_name>.*) other info2 \d* etc') TABLE_LINE = 2 PLAYER_REGEX = re.compile(r'^Seat \d: (?P<player_name>.*) has a stack of (\d*)') PLAYER_LINE = 14 So if I want to make it possible for non-developers to write these classes the way to go seems to be the declarative way, however, I'm almost certain I can't eliminate the declarations of regexes, which clearly needs (senior :D) programmers, so should I care about this at all? Do you think it matters to choose one over another or doesn't matter at all? Maybe if somebody wants to work on this project, they will, if not, no matter which idiom I choose. Can I "convert" non-programmers to help developing these? What are your observations? Other considerations: Imperative will allow any kind of work; there is a simple flow, which they can follow but inside that, they can do whatever they want. It would be harder to force a common interface with imperative because of this arbitrary implementations. Declarative will be much more rigid, which is a bad thing, because formats might change over time without any notice. Declarative will be harder for me to develop and takes longer time. Imperative is already ready to release. I hope a nice discussion will happen in this thread about programming idioms regarding which to use when, which is better for open source projects with different scenarios, which is better for wide range of developer skills. TL; DR: Parsing different file formats (plain text, XML) They contains same kind of information Target audience: non-developers, beginners Regex probably cannot be avoided 30-40 concrete parser classes needed Facilitate coding these concrete classes Which idiom is better?

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• Programação paralela no .NET Framework 4 – Parte II

  - by anobre

  Olá pessoal, tudo bem? Este post é uma continuação da série iniciada neste outro post, sobre programação paralela. Meu objetivo hoje é apresentar o PLINQ, algo que poderá ser utilizado imediatamente nos projetos de vocês. Parallel LINQ (PLINQ) PLINQ nada mais é que uma implementação de programação paralela ao nosso famoso LINQ, através de métodos de extensão. O LINQ foi lançado com a versão 3.0 na plataforma .NET, apresentando uma maneira muito mais fácil e segura de manipular coleções IEnumerable ou IEnumerable<T>. O que veremos hoje é a “alteração” do LINQ to Objects, que é direcionado a coleções de objetos em memória. A principal diferença entre o LINQ to Objects “normal” e o paralelo é que na segunda opção o processamento é realizado tentando utilizar todos os recursos disponíveis para tal, obtendo uma melhora significante de performance. CUIDADO: Nem todas as operações ficam mais rápidas utilizando recursos de paralelismo. Não deixe de ler a seção “Performance” abaixo. ParallelEnumerable Tudo que a gente precisa para este post está organizado na classe ParallelEnumerable. Esta classe contém os métodos que iremos utilizar neste post, e muito mais: AsParallel AsSequential AsOrdered AsUnordered WithCancellation WithDegreeOfParallelism WithMergeOptions WithExecutionMode ForAll … O exemplo mais básico de como executar um código PLINQ é utilizando o métodos AsParallel, como o exemplo: var source = Enumerable.Range(1, 10000); var evenNums = from num in source.AsParallel() where Compute(num) > 0 select num; Algo tão interessante quanto esta facilidade é que o PLINQ não executa sempre de forma paralela. Dependendo da situação e da análise de alguns itens no cenário de execução, talvez seja mais adequado executar o código de forma sequencial – e nativamente o próprio PLINQ faz esta escolha.  É possível forçar a execução para sempre utilizar o paralelismo, caso seja necessário. Utilize o método WithExecutionMode no seu código PLINQ. Um teste muito simples onde podemos visualizar a diferença é demonstrado abaixo: static void Main(string[] args) { IEnumerable<int> numbers = Enumerable.Range(1, 1000); IEnumerable<int> results = from n in numbers.AsParallel() where IsDivisibleByFive(n) select n; Stopwatch sw = Stopwatch.StartNew(); IList<int> resultsList = results.ToList(); Console.WriteLine("{0} itens", resultsList.Count()); sw.Stop(); Console.WriteLine("Tempo de execução: {0} ms", sw.ElapsedMilliseconds); Console.WriteLine("Fim..."); Console.ReadKey(true); } static bool IsDivisibleByFive(int i) { Thread.SpinWait(2000000); return i % 5 == 0; }   Basta remover o AsParallel da instrução LINQ que você terá uma noção prática da diferença de performance. 1. Instrução utilizando AsParallel   2. Instrução sem utilizar paralelismo Performance Apesar de todos os benefícios, não podemos utilizar PLINQ sem conhecer todos os seus detalhes. Lembre-se de fazer as perguntas básicas: Eu tenho trabalho suficiente que justifique utilizar paralelismo? Mesmo com o overhead do PLINQ, vamos ter algum benefício? Por este motivo, visite este link e conheça todos os aspectos, antes de utilizar os recursos disponíveis. Conclusão Utilizar recursos de paralelismo é ótimo, aumenta a performance, utiliza o investimento realizado em hardware – tudo isso sem custo de produtividade. Porém, não podemos usufruir de qualquer tipo de tecnologia sem conhece-la a fundo antes. Portanto, faça bom uso, mas não esqueça de manter o conhecimento a frente da empolgação. Abraços.

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• Initializing and drawing a mesh using OpenTK

  - by Boreal

  I'm implementing a "Mesh" class to use in my OpenTK game. You pass in a vertex array and an index array, and then you can call Mesh.Draw() to draw it using a shader. I've heard VBO's and VAO's are the way to go for this approach, but nowhere have I found a guide that shows how to get Data Video Memory Shader. Can someone give me a quick rundown of how this works? EDIT: So far, I have this: struct Vertex { public Vector3 position; public Vector3 normal; public Vector3 color; public static int memSize = 9 * sizeof(float); public static byte[] memOffset = { 0, 3 * sizeof(float), 6 * sizeof(float) }; } class Mesh { private uint vbo; private uint ibo; // stores the numbers of vertices and indices private int numVertices; private int numIndices; public Mesh(int numVertices, Vertex[] vertices, int numIndices, ushort[] indices) { // set numbers this.numVertices = numVertices; this.numIndices = numIndices; // generate buffers GL.GenBuffers(1, out vbo); GL.GenBuffers(1, out ibo); GL.BindBuffer(BufferTarget.ArrayBuffer, vbo); GL.BindBuffer(BufferTarget.ElementArrayBuffer, ibo); // send data to the buffers GL.BufferData(BufferTarget.ArrayBuffer, new IntPtr(Vertex.memSize * numVertices), vertices, BufferUsageHint.StaticDraw); GL.BufferData(BufferTarget.ElementArrayBuffer, new IntPtr(sizeof(ushort) * numIndices), indices, BufferUsageHint.StaticDraw); } public void Render() { // bind buffers GL.BindBuffer(BufferTarget.ArrayBuffer, vbo); GL.BindBuffer(BufferTarget.ElementArrayBuffer, ibo); // define offsets GL.VertexPointer(3, VertexPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[0])); GL.NormalPointer(NormalPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[1])); GL.ColorPointer(3, ColorPointerType.Float, Vertex.memSize, new IntPtr(Vertex.memOffset[2])); // draw GL.DrawElements(BeginMode.Triangles, numIndices, DrawElementsType.UnsignedInt, (IntPtr)0); } } class Application : GameWindow { Mesh triangle; protected override void OnLoad(EventArgs e) { base.OnLoad(e); GL.ClearColor(0.1f, 0.2f, 0.5f, 0.0f); GL.Enable(EnableCap.DepthTest); GL.Enable(EnableCap.VertexArray); GL.Enable(EnableCap.NormalArray); GL.Enable(EnableCap.ColorArray); Vertex v0 = new Vertex(); v0.position = new Vector3(-1.0f, -1.0f, 4.0f); v0.normal = new Vector3(0.0f, 0.0f, -1.0f); v0.color = new Vector3(1.0f, 1.0f, 0.0f); Vertex v1 = new Vertex(); v1.position = new Vector3(1.0f, -1.0f, 4.0f); v1.normal = new Vector3(0.0f, 0.0f, -1.0f); v1.color = new Vector3(1.0f, 0.0f, 0.0f); Vertex v2 = new Vertex(); v2.position = new Vector3(0.0f, 1.0f, 4.0f); v2.normal = new Vector3(0.0f, 0.0f, -1.0f); v2.color = new Vector3(0.2f, 0.9f, 1.0f); Vertex[] va = { v0, v1, v2 }; ushort[] ia = { 0, 1, 2 }; triangle = new Mesh(3, va, 3, ia); } protected override void OnRenderFrame(FrameEventArgs e) { base.OnRenderFrame(e); GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); Matrix4 modelview = Matrix4.LookAt(Vector3.Zero, Vector3.UnitZ, Vector3.UnitY); GL.MatrixMode(MatrixMode.Modelview); GL.LoadMatrix(ref modelview); triangle.Render(); SwapBuffers(); } } It doesn't draw anything.

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• Oracle Functional Testing Suite Advanced Pack for Oracle EBS Now Available

  - by Anne Carlson (Oracle Development)

  There’s new news about automated testing of E-Business Suite using the Oracle Application Testing Suite, a.k.a, “OATS”. E-Business Suite Development is pleased to announce the availability of the new Oracle Functional Testing Suite Advanced Pack for Oracle E-Business Suite. The new pack, available with the latest release of Oracle Application Testing Suite (12.4.0.2), provides pre-built test components and flows to automate the in-depth testing of Oracle E-Business Suite applications. Designed for use with the Oracle Application Testing Suite and its Oracle Flow Builder capability, these pre-built components and flows can help Oracle E-Business Suite customers to significantly reduce the time and effort needed to create and maintain automated test scripts. The Oracle Functional Testing Suite Advanced Pack for Oracle E-Business Suite is available now for EBS 12.1.3, and availability for EBS 12.2 is planned. Some Background on Automating Testing with Oracle Application Testing Suite and Oracle Flow Builder      Testing complex packaged applications like Oracle E-Business Suite can be time-consuming and challenging for organizations, hampering their ability to upgrade to latest releases or apply latest patches. Oracle Application Testing Suite offers organizations a unique and powerful testing platform for Oracle E-Business Suite and other Oracle applications. With the 12.3.0.1 release of Oracle Application Testing Suite, we introduced the Oracle Flow Builder testing framework and accompanying starter pack of pre-built test components and flows. The starter pack, which contains over 2000 components and 200 flows, provides broad coverage of commonly-used base functionality and is designed to jump-start the test automation effort. Using Oracle Flow Builder, even non-technical testers can create working test scripts using the pre-built components that Oracle provides. Each component represents an atomic test operation such as “create an invoice batch” or “apply an invoice hold.” Testers can assemble the pre-built components into test flows, and combine test flows with spreadsheet data to drive the testing of multiple data conditions. The Oracle Flow Builder framework allows customers to add, modify and extend the pre-built components to address new functionality and customizations of the Oracle E-Business Suite. Using Oracle Flow Builder’s component-based test generation framework instead of a traditional record/playback approach has allowed the EBS Quality Assurance team to reduce their test automation effort by 60%. E-Business Suite customers can significantly reduce their test automation effort using Oracle Application Testing Suite with Oracle Flow Builder and the pre-built test components and flows that Oracle provides. Oracle Functional Testing Suite Advanced Pack for Oracle E-Business Suite Improves Test Coverage With the Oracle Application Testing Suite 12.4.0.2 and the new Oracle Functional Testing Suite Advanced Pack for Oracle E-Business Suite, we are now delivering a significant number of additional test components and flows beyond those contained in the Oracle Flow Builder starter pack. These additional test components and flows provide 70-80% test coverage and enable the automation of detailed and complex test flows across the following Oracle E-Business Suite products: Oracle Asset Lifecycle Management Oracle Channel Revenue Management Oracle Discrete Manufacturing Oracle Incentive Compensation Oracle Lease and Finance Management Oracle Process Manufacturing Oracle Procurement Oracle Project Management Oracle Property Manager Oracle Service Downloads You can download the Oracle Functional Testing Suite Advanced Pack for Oracle E-Business Suite from the Oracle Technology Network. References Oracle Applications Testing Suite YouTube: Oracle Flow Builder Training YouTube: Oracle Applications Testing Suite and Flow Builder Demonstration Oracle Functional Testing Suite Advanced Pack Readme for E-Business Suite, id=1905989.1">Note 1905989.1 Related Articles Automate Testing Using Oracle Application Testing Suite with Flow Builder for E-Business Suite EBS 12.1.1 Test Starter Kit Now Available for Oracle Applications Testing Suite Oracle Application Testing Suite 9.0 Supported with Oracle E-Business Suite Using the Oracle Application Testing Suite with EBS: Interim Update #1

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• Don’t miss this very popular presentation on Punchout in iProcurement on June 26th 2012

  - by user793553

  Don’t miss this very popular presentation on Punchout in iProcurement on June 26th.  See Doc ID 1448447.1 for the Webcast details. ADVISOR WEBCAST: Punchout in iProcurement PRODUCT FAMILY: EBZs- Procurement   June 26, 2012 at 14:00 UK / 15:00 Cairo / 6:00 am Pacific / 7:00 am Mountain / 9:00 am Eastern This one-hour session is recommended for technical and functional users who are maintaining and/or implementing the Punchout from iProcurement. The session will provide an overview of the different Punchout model, setup, and the Punchout to PO xml/cxml cycle. Also, it will provide tips in troubleshooting the common issues when new supplier is added to Punchout or the existing one stops working. TOPICS WILL INCLUDE: Overview of the Punchout Models. Provide the knowledge in the Punchout to PO Process cycle. Demo - Punchout. Certificates and setup. Learn the common issues and how to address in an efficient way. (Documentation and Notes) A short, live demonstration (only if applicable) and question and answer period will be included. Oracle Advisor Webcasts are dedicated to building your awareness around our products and services. This session does not replace offerings from Oracle Global Support Services. Current Schedule can be found on Note 740966.1 Post Presentation Recordings can be found on Note 740964.1 WebEx Conference Details Topic: Advisor Webcast - Punchout in iProcuremen Date and Time: Tuesday, June 26, 2012 3:00 pm, Egypt Time (Cairo, GMT+02:00) Tuesday, June 26, 2012 2:00 pm, GMT Summer Time (London, GMT+01:00) Tuesday, June 26, 2012 9:00 am, Eastern Daylight Time (New York, GMT-04:00) Tuesday, June 26, 2012 7:00 am, Mountain Daylight Time (Denver, GMT-06:00) Event number: 597 373 155 -------------------------------------------------------  To register for this meeting  -------------------------------------------------------  1. Event address for attendees: https://oracleaw.webex.com/oracleaw/onstage/g.php?d=597373155&t=a 2. Register for the meeting.  Once the host approves your request, you will receive a confirmation email with instructions for joining the meeting. InterCall Audio Instructions A list of Toll-Free Numbers can be found below. VOICESTREAMING IS AVAILABLE teleconference ID: 70528713 UK standard International:+44 1452 562 665 US Free Call: 1866 230 1938 US Local call: 1845 608 8023 Global Toll-Free Numbers MOS doc#:  https://metalink3.oracle.com/od/faces/secure/km/DocumentDisplay.jspx?id=1148600.1 Designation Number Argentina Free Call 0800 444 1009 Australia Free Call 1800 763 650 Austria Free Call 0800 111 956 Austria Local Call 0192 865 72 Belgium Free Call 0800 724 46 Belgium Local Call 0817 000 60 Brazil Free Call 0800 761 0835 Bulgaria Free Call 0080 011 511 76 Canada Free Call 1866 984 6577 Columbia Free Call 0180 091 562 17 Croatia Free Call 0800 222 305 Cyprus Free Call 8009 6341 Czech Republic Free Call 8007 007 95 Denmark Free Call 8088 8467 Denmark Local Call 3272 7506 Finland Free Call 0800 112 398 Finland Local Call 0923 114 014 France Free Call 0805 110 463 France Local Call 0359 580 290 Germany Free Call 0800 101 4918 Germany Local Call 0692 222 161 19 Greece Free Call 0080 012 8135 Hong Kong Free Call 8009 661 55 Hungary Free Call 0680 018 839 Hungary Local Call 0180 889 97 India Free Call 0008 001 006 600 Ireland Free Call 1800 300 170 Ireland Local Call 0143 198 35 Israel Free Call 1809 431 440 Italy Free Call 8007 840 87 Italy Local Call 0236 009 700 Japan Free Call 0066 338 124 31 Latvia Free Call 8000 3680 Luxembourg Free Call 8002 7941 Malaysia Free Call 1800 814 528 Mexico Free Call 0018 666 864 905 Monaco Free Call 8009 3655 Netherlands Free Call 0800 949 4596 Netherlands Local Call 0207 168 000 New Zealand Free Call 0800 451 190 North China Free Call 1080 074 413 29 Norway Free Call 8001 8057 Norway Local Call 2151 0847 Poland Free Call 0080 012 135 73 Portugal Free Call 8007 894 20 Romania Free Call 0800 895 558 Russia Free Call 8108 002 385 2044 Slovenia Free Call 0800 804 55 South Africa Free Call 0800 982 794 South China Free Call 1080 044 111 82 South Korea Free Call 0079 814 800 7887 Spain Free Call 9009 389 85 Spain Local Call 9111 421 10 Sweden Free Call 0200 214 344 Sweden Local Call 0850 596 375 Switzerland Free Call 0800 835 040 Switzerland Local Call 0445 804 280 Thailand Free Call 0018 004 421 98 UK Free Call 0800 073 1830 UK Local Call 0844 871 9364 UK National Call 0871 700 0309 UK Standard International +44 (0) 1452 562 665 USA Free Call 1866 230 1938   Back to the top   Copyright? 2010, Oracle. All rights reserved. Contact Us | Legal Notices and Terms of Use | Privacy Statement

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• ASP.NET Web API - Screencast series with downloadable sample code - Part 1

  - by Jon Galloway

  There's a lot of great ASP.NET Web API content on the ASP.NET website at http://asp.net/web-api. I mentioned my screencast series in original announcement post, but we've since added the sample code so I thought it was worth pointing the series out specifically. This is an introductory screencast series that walks through from File / New Project to some more advanced scenarios like Custom Validation and Authorization. The screencast videos are all short (3-5 minutes) and the sample code for the series is both available for download and browsable online. I did the screencasts, but the samples were written by the ASP.NET Web API team. So - let's watch them together! Grab some popcorn and pay attention, because these are short. After each video, I'll talk about what I thought was important. I'm embedding the videos using HTML5 (MP4) with Silverlight fallback, but if something goes wrong or your browser / device / whatever doesn't support them, I'll include the link to where the videos are more professionally hosted on the ASP.NET site. Note also if you're following along with the samples that, since Part 1 just looks at the File / New Project step, the screencast part numbers are one ahead of the sample part numbers - so screencast 4 matches with sample code demo 3. Note: I started this as one long post for all 6 parts, but as it grew over 2000 words I figured it'd be better to break it up. Part 1: Your First Web API [Video and code on the ASP.NET site] This screencast starts with an overview of why you'd want to use ASP.NET Web API: Reach more clients (thinking beyond the browser to mobile clients, other applications, etc.) Scale (who doesn't love the cloud?!) Embrace HTTP (a focus on HTTP both on client and server really simplifies and focuses service interactions) Next, I start a new ASP.NET Web API application and show some of the basics of the ApiController. We don't write any new code in this first step, just look at the example controller that's created by File / New Project. using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace NewProject_Mvc4BetaWebApi.Controllers { public class ValuesController : ApiController { // GET /api/values public IEnumerable<string> Get() { return new string[] { "value1", "value2" }; } // GET /api/values/5 public string Get(int id) { return "value"; } // POST /api/values public void Post(string value) { } // PUT /api/values/5 public void Put(int id, string value) { } // DELETE /api/values/5 public void Delete(int id) { } } } Finally, we walk through testing the output of this API controller using browser tools. There are several ways you can test API output, including Fiddler (as described by Scott Hanselman in this post) and built-in developer tools available in all modern browsers. For simplicity I used Internet Explorer 9 F12 developer tools, but you're of course welcome to use whatever you'd like. A few important things to note: This class derives from an ApiController base class, not the standard ASP.NET MVC Controller base class. They're similar in places where API's and HTML returning controller uses are similar, and different where API and HTML use differ. A good example of where those things are different is in the routing conventions. In an HTTP controller, there's no need for an "action" to be specified, since the HTTP verbs are the actions. We don't need to do anything to map verbs to actions; when a request comes in to /api/values/5 with the DELETE HTTP verb, it'll automatically be handled by the Delete method in an ApiController. The comments above the API methods show sample URL's and HTTP verbs, so we can test out the first two GET methods by browsing to the site in IE9, hitting F12 to bring up the tools, and entering /api/values in the URL: That sample action returns a list of values. To get just one value back, we'd browse to /values/5: That's it for Part 1. In Part 2 we'll look at getting data (beyond hardcoded strings) and start building out a sample application.

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• Restricting Input in HTML Textboxes to Numeric Values

  - by Rick Strahl

  Ok, here’s a fairly basic one – how to force a textbox to accept only numeric input. Somebody asked me this today on a support call so I did a few quick lookups online and found the solutions listed rather unsatisfying. The main problem with most of the examples I could dig up was that they only include numeric values, but that provides a rather lame user experience. You need to still allow basic operational keys for a textbox – navigation keys, backspace and delete, tab/shift tab and the Enter key - to work or else the textbox will feel very different than a standard text box. Yes there are plug-ins that allow masked input easily enough but most are fixed width which is difficult to do with plain number input. So I took a few minutes to write a small reusable plug-in that handles this scenario. Imagine you have a couple of textboxes on a form like this: <div class="containercontent"> <div class="label">Enter a number:</div> <input type="text" name="txtNumber1" id="txtNumber1" value="" class="numberinput" /> <div class="label">Enter a number:</div> <input type="text" name="txtNumber2" id="txtNumber2" value="" class="numberinput" /> </div> and you want to restrict input to numbers. Here’s a small .forceNumeric() jQuery plug-in that does what I like to see in this case: [Updated thanks to Elijah Manor for a couple of small tweaks for additional keys to check for] <script type="text/javascript"> $(document).ready(function () { $(".numberinput").forceNumeric(); }); // forceNumeric() plug-in implementation jQuery.fn.forceNumeric = function () { return this.each(function () { $(this).keydown(function (e) { var key = e.which || e.keyCode; if (!e.shiftKey && !e.altKey && !e.ctrlKey && // numbers key >= 48 && key <= 57 || // Numeric keypad key >= 96 && key <= 105 || // comma, period and minus key == 190 || key == 188 || key == 109 || // Backspace and Tab and Enter key == 8 || key == 9 || key == 13 || // Home and End key == 35 || key == 36 || // left and right arrows key == 37 || key == 39 || // Del and Ins key == 46 || key == 45) return true; return false; }); }); } </script> With the plug-in in place in your page or an external .js file you can now simply use a selector to apply it: $(".numberinput").forceNumeric(); The plug-in basically goes through each selected element and hooks up a keydown() event handler. When a key is pressed the handler is fired and the keyCode of the event object is sent. Recall that jQuery normalizes the JavaScript Event object between browsers. The code basically white-lists a few key codes and rejects all others. It returns true to indicate the keypress is to go through or false to eat the keystroke and not process it which effectively removes it. Simple and low tech, and it works without too much change of typical text box behavior.© Rick Strahl, West Wind Technologies, 2005-2011Posted in JavaScript  jQuery  HTML  

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• From NaN to Infinity...and Beyond!

  - by Tony Davis

  It is hard to believe that it was once possible to corrupt a SQL Server Database by storing perfectly normal data values into a table; but it is true. In SQL Server 2000 and before, one could inadvertently load invalid data values into certain data types via RPC calls or bulk insert methods rather than DML. In the particular case of the FLOAT data type, this meant that common 'special values' for this type, namely NaN (not-a-number) and +/- infinity, could be quite happily plugged into the database from an application and stored as 'out-of-range' values. This was like a time-bomb. When one then tried to query this data; the values were unsupported and so data pages containing them were flagged as being corrupt. Any query that needed to read a column containing the special value could fail or return unpredictable results. Microsoft even had to issue a hotfix to deal with failures in the automatic recovery process, caused by the presence of these NaN values, which rendered the whole database inaccessible! This problem is history for those of us on more current versions of SQL Server, but its ghost still haunts us. Recently, for example, a developer on Red Gate’s SQL Response team reported a strange problem when attempting to load historical monitoring data into a SQL Server 2005 database via the C# ADO.NET provider. The ratios used in some of their reporting calculations occasionally threw out NaN or infinity values, and the subsequent attempts to load these values resulted in a nasty error. It turns out to be a different manifestation of the same problem. SQL Server 2005 still does not fully support the IEEE 754 standard for floating point numbers, in that the FLOAT data type still cannot handle NaN or infinity values. Instead, they just added validation checks that prevent the 'invalid' values from being loaded in the first place. For people migrating from SQL Server 2000 databases that contained out-of-range FLOAT (or DATETIME etc.) data, to SQL Server 2005, Microsoft have added to the latter's version of the DBCC CHECKDB (or CHECKTABLE) command a DATA_PURITY clause. When enabled, this will seek out the corrupt data, but won’t fix it. You have to do this yourself in what can often be a slow, painful manual process. Our development team, after a quizzical shrug of the shoulders, simply decided to represent NaN and infinity values as NULL, and move on, accepting the minor inconvenience of not being able to tell them apart. However, what of scientific, engineering and other applications that really would like the luxury of being able to both store and access these perfectly-reasonable floating point data values? The sticking point seems to be the stipulation in the IEEE 754 standard that, when NaN is compared to any other value including itself, the answer is "unequal" (i.e. FALSE). This is clearly different from normal number comparisons and has repercussions for such things as indexing operations. Even so, this hardly applies to infinity values, which are single definite values. In fact, there is some encouraging talk in the Connect note on this issue that they might be supported 'in the SQL Server 2008 timeframe'. If didn't happen; SQL 2008 doesn't support NaN or infinity values, though one could be forgiven for thinking otherwise, based on the MSDN documentation for the FLOAT type, which states that "The behavior of float and real follows the IEEE 754 specification on approximate numeric data types". However, the truth is revealed in the XPath documentation, which states that "…float (53) is not exactly IEEE 754. For example, neither NaN (Not-a-Number) nor infinity is used…". Is it really so hard to fix this problem the right way, and properly support in SQL Server the IEEE 754 standard for the floating point data type, NaNs, infinities and all? Oracle seems to have managed it quite nicely with its BINARY_FLOAT and BINARY_DOUBLE types, so it is technically possible. We have an enterprise-class database that is marketed as being part of an 'integrated' Windows platform. Absurdly, we have .NET and XPath libraries that fully support the standard for floating point numbers, and we can't even properly store these values, let alone query them, in the SQL Server database! Cheers, Tony.

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• Calling XAI Inbound Services from Oracle BI Publisher

  - by ACShorten

  Note: This technique requires Oracle BI Publisher 1.1.3.4.1 which supports Service Complex Types. Web Services require credentials for authentication. Note: The deafults for the product installation are used in this article. If your site uses alternative values then substitute those alternatives where applicable. Note: Examples shown in this article are examples for illustrative purposes only. When building a report in Oracle BI Publisher it may be necessary to call an XAI Inbound Service to get information via the object rather than directly calling the database tables for various reasons: The CLOB fields used in the Object are accessible for a report. Note: CLOB fields cannot be used as criteria in the current release. Objects can take advantage of algorithms to format or calculate additional data that is not stored in the database directly. For example, Information format strings can automatically generated by the object which gives consistent information between a report and the online screens. To use this facility the following process must be performed: Ensure that the product group, cisusers by default, is enabled for the SPLServiceBean in the console. This allows BI Publisher access to call Web Services directly. To ensure this follow the instructions below: Logon to the Oracle WebLogic server console using an appropriate administrator account. By default the user system or weblogic is provided for this purpose. Navigate to the Security Realms section and select your configured realm. This is set to myrealm by default. In the Roles and Policies section, expand the SPLService section of the Deployments option to reveal the SPLServiceBean roles. If there is no role associated with the SPLServiceBean, create a new EJB role and specify the cisusers role, by default. For example:   Add a Role Condition to the role just created, with a Predicate List of Group and specify cisusers as the Group Argument Name. For example: Save all your changes. The XAI Inbound Services to be used by BI Publisher must be defined prior to using the interface. Refer to the XAI Best Practices (Doc Id: 942074.1) from My Oracle Support or via the online help for more information about this process. Inside BI Publisher create your report, according to the BI Publisher documentation. When specifying the dataset, under the Data Model Report option, specify the following to use an XAI Inbound Service as a data source: Parameter Comment Type Web Service Complex Type true Username Any valid user name within the product. This user MUST have security access to the objects referenced in the XAI Inbound Service Password Authentication password for Username Timeout Timeout, in seconds, set for the Web Service call. For example 60 seconds. WSDL URL Use the WSDL URL on the XAI Inbound Service definition as your WSDL URL. It will be in the following format by default:http://<host>:<port>/<server>/XAIApp/xaiserver/<service>?WSDLwhere: <host> - Host Name of Web Application Server <port> - Port allocated to Web Application Server for product access <server> - Server context for server <service> - XAI Inbound Service Name Note: For customers using secure transmission should substitute https instead of http and use the HTTPS port allocated to the product at installation time. Web Service Select the name of the service that shows in the drop-down menu. If no service name shows up, it means that Publisher could not establish a connection with the server or WSDL name provided in the above URL in order to get the service name. See BI Publisher server log for more information. Method Select the name of the Method that shows in the drop-down menu. A method name should show in the Method drop-down menu once the Web Service name is selected. For example: Additionally, filters can be used from the Web Service that can be generated, required or optional, from the WSDL in the Parameter List. For example:

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• Speed up SQL Server queries with PREFETCH

  - by Akshay Deep Lamba

  Problem The SAN data volume has a throughput capacity of 400MB/sec; however my query is still running slow and it is waiting on I/O (PAGEIOLATCH_SH). Windows Performance Monitor shows data volume speed of 4MB/sec. Where is the problem and how can I find the problem? Solution This is another summary of a great article published by R. Meyyappan at www.sqlworkshops.com.  In my opinion, this is the first article that highlights and explains with working examples how PREFETCH determines the performance of a Nested Loop join.  First of all, I just want to recall that Prefetch is a mechanism with which SQL Server can fire up many I/O requests in parallel for a Nested Loop join. When SQL Server executes a Nested Loop join, it may or may not enable Prefetch accordingly to the number of rows in the outer table. If the number of rows in the outer table is greater than 25 then SQL will enable and use Prefetch to speed up query performance, but it will not if it is less than 25 rows. In this section we are going to see different scenarios where prefetch is automatically enabled or disabled. These examples only use two tables RegionalOrder and Orders.  If you want to create the sample tables and sample data, please visit this site www.sqlworkshops.com. The breakdown of the data in the RegionalOrders table is shown below and the Orders table contains about 6 million rows. In this first example, I am creating a stored procedure against two tables and then execute the stored procedure.  Before running the stored proceudre, I am going to include the actual execution plan. --Example provided by www.sqlworkshops.com --Create procedure that pulls orders based on City --Do not forget to include the actual execution plan CREATE PROC RegionalOrdersProc @City CHAR(20) AS BEGIN DECLARE @OrderID INT, @OrderDetails CHAR(200) SELECT @OrderID = o.OrderID, @OrderDetails = o.OrderDetails       FROM RegionalOrders ao INNER JOIN Orders o ON (o.OrderID = ao.OrderID)       WHERE City = @City END GO SET STATISTICS time ON GO --Example provided by www.sqlworkshops.com --Execute the procedure with parameter SmallCity1 EXEC RegionalOrdersProc 'SmallCity1' GO After running the stored procedure, if we right click on the Clustered Index Scan and click Properties we can see the Estimated Numbers of Rows is 24.    If we right click on Nested Loops and click Properties we do not see Prefetch, because it is disabled. This behavior was expected, because the number of rows containing the value ‘SmallCity1’ in the outer table is less than 25.   Now, if I run the same procedure with parameter ‘BigCity’ will Prefetch be enabled? --Example provided by www.sqlworkshops.com --Execute the procedure with parameter BigCity --We are using cached plan EXEC RegionalOrdersProc 'BigCity' GO As we can see from the below screenshot, prefetch is not enabled and the query takes around 7 seconds to execute. This is because the query used the cached plan from ‘SmallCity1’ that had prefetch disabled. Please note that even if we have 999 rows for ‘BigCity’ the Estimated Numbers of Rows is still 24.   Finally, let’s clear the procedure cache to trigger a new optimization and execute the procedure again. DBCC freeproccache GO EXEC RegionalOrdersProc 'BigCity' GO This time, our procedure runs under a second, Prefetch is enabled and the Estimated Number of Rows is 999.   The RegionalOrdersProc can be optimized by using the below example where we are using an optimizer hint. I have also shown some other hints that could be used as well. --Example provided by www.sqlworkshops.com --You can fix the issue by using any of the following --hints --Create procedure that pulls orders based on City DROP PROC RegionalOrdersProc GO CREATE PROC RegionalOrdersProc @City CHAR(20) AS BEGIN DECLARE @OrderID INT, @OrderDetails CHAR(200) SELECT @OrderID = o.OrderID, @OrderDetails = o.OrderDetails       FROM RegionalOrders ao INNER JOIN Orders o ON (o.OrderID = ao.OrderID)       WHERE City = @City       --Hinting optimizer to use SmallCity2 for estimation       OPTION (optimize FOR (@City = 'SmallCity2'))       --Hinting optimizer to estimate for the currnet parameters       --option (recompile)       --Hinting optimize not to use histogram rather       --density for estimation (average of all 3 cities)       --option (optimize for (@City UNKNOWN))       --option (optimize for UNKNOWN) END GO Conclusion, this tip was mainly aimed at illustrating how Prefetch can speed up query execution and how the different number of rows can trigger this.

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• How Exactly Is One Linux OS “Based On” Another Linux OS?

  - by Jason Fitzpatrick

  When reviewing different flavors of Linux, you’ll frequently come across phrases like “Ubuntu is based on Debian” but what exactly does that mean? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader PLPiper is trying to get a handle on how Linux variants work: I’ve been looking through quite a number of Linux distros recently to get an idea of what’s around, and one phrase that keeps coming up is that “[this OS] is based on [another OS]“. For example: Fedora is based on Red Hat Ubuntu is based on Debian Linux Mint is based on Ubuntu For someone coming from a Mac environment I understand how “OS X is based on Darwin”, however when I look at Linux Distros, I find myself asking “Aren’t they all based on Linux..?” In this context, what exactly does it mean for one Linux OS to be based on another Linux OS? So, what exactly does it mean when we talk about one version of Linux being based off another version? The Answer SuperUser contributor kostix offers a solid overview of the whole system: Linux is a kernel — a (complex) piece of software which works with the hardware and exports a certain Application Programming Interface (API), and binary conventions on how to precisely use it (Application Binary Interface, ABI) available to the “user-space” applications. Debian, RedHat and others are operating systems — complete software environments which consist of the kernel and a set of user-space programs which make the computer useful as they perform sensible tasks (sending/receiving mail, allowing you to browse the Internet, driving a robot etc). Now each such OS, while providing mostly the same software (there are not so many free mail server programs or Internet browsers or desktop environments, for example) differ in approaches to do this and also in their stated goals and release cycles. Quite typically these OSes are called “distributions”. This is, IMO, a somewhat wrong term stemming from the fact you’re technically able to build all the required software by hand and install it on a target machine, so these OSes distribute the packaged software so you either don’t need to build it (Debian, RedHat) or they facilitate such building (Gentoo). They also usually provide an installer which helps to install the OS onto a target machine. Making and supporting an OS is a very complicated task requiring a complex and intricate infrastructure (upload queues, build servers, a bug tracker, and archive servers, mailing list software etc etc etc) and staff. This obviously raises a high barrier for creating a new, from-scratch OS. For instance, Debian provides ca. 37k packages for some five hardware architectures — go figure how much work is put into supporting this stuff. Still, if someone thinks they need to create a new OS for whatever reason, it may be a good idea to use an existing foundation to build on. And this is exactly where OSes based on other OSes come into existence. For instance, Ubuntu builds upon Debian by just importing most packages from it and repackaging only a small subset of them, plus packaging their own, providing their own artwork, default settings, documentation etc. Note that there are variations to this “based on” thing. For instance, Debian fosters the creation of “pure blends” of itself: distributions which use Debian rather directly, and just add a bunch of packages and other stuff only useful for rather small groups of users such as those working in education or medicine or music industry etc. Another twist is that not all these OSes are based on Linux. For instance, Debian also provide FreeBSD and Hurd kernels. They have quite tiny user groups but anyway. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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• Oracle at The Forrester Customer Intelligence and Marketing Leadership Forums

  - by Christie Flanagan

  The Forrester Customer Intelligence Forum and the Forrester Marketing Leadership Forums will soon be here.  This year’s events will be co-located on April 18-19 at the J.W. Marriott at the L.A. Live entertainment complex in downtown Los Angeles.  Last year’s Marketing Forum was quite memorable for me.  You see, while Forrester analysts and business marketers were busy mingling over at the Marriott, another marketing powerhouse was taking up residence a few feet away at The Staples Center.  That’s right folks. Lada Gaga was coming to town.  And, as I came to learn, it made perfect sense for Lady Gaga and her legions of fans to be sharing a small patch of downtown L.A. with marketing leaders from all over the world.  After all, whether you like Lady Gaga or not, what pop star in recent memory has done more to build herself into a brand and to create an engaging, social and interactive customer experience for her Little Monsters?  While Lady Gaga won’t be back in town for this year’s Forrester events, there are still plenty of compelling reasons to make the trip out to Los Angeles.   The theme for The Forrester Customer Intelligence and Marketing Leadership Forums this year is “From Cool To Critical: Creating Engagement In The Age Of The Customer” and will tackle the important questions about how marketers can survive and thrive in the age of the empowered customer: •    How can you assess consumer uptake of new innovations?•    How do you build deep customer knowledge to drive competitive advantage?•    How do you drive deep, personalized customer engagement?•    What is more valuable — eyeballs or engagement?•    How do business customers engage in new media types?•    How can you tie social data to corporate data?•    Who should lead the movement to customer obsession?•    How should you shift your planning and measurement approaches to accommodate more data and a higher signal-to-noise ratio?•    What role does technology play in customizing and synchronizing marketing efforts across channels?As a platinum sponsor of the event, there will be a numbers of ways to interact with Oracle while you’re attending the Forums.  Here are some of the highlights:Oracle Speaking SessionThursday, April 19, 9:15am – 9:55amMaximize Customer Engagement and Retention with Integrated Marketing & LoyaltyMelissa Boxer, Vice President, Oracle CRM Marketing & LoyaltyCustomers expect to interact with your company, brand and products in more ways than ever before.   New devices and channels, such as mobile, social and web, are creating radical shifts in the customer buying process and the ways your company can reach and communicate with existing and potential customers. While Marketing's objectives (attract, convert, retain) remain fundamentally the same, your approach and tools must adapt quickly to succeed in this more complex, cross-channel world. Hear how leading brands are using Oracle's integrated marketing and loyalty solutions to maximize customer engagement and retention through better planning, execution, and measurement of synchronized cross-channel marketing initiatives.Solution ShowcaseWednesday, April 1810:20am – 11:50am 12:30pm – 1:30pm2:55pm – 3:40pmThursday, April 199:55am – 10:40am12:00pm – 1:00pmSolution Showcase & Networking ReceptionWednesday, April 185:10pm – 6:20pmBe sure to follow the #webcenter hashtag for updates on these events.  And for a more considered perspective on what Lady Gaga can teach businesses about branding and customer experience, check out Denise Lee Yohn’s post, Lessons from Lady Gaga from the Brand as Business Bites blog.

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• Filtering data in LINQ with the help of where clause

  - by vik20000in

   LINQ has bought with itself a super power of querying Objects, Database, XML, SharePoint and nearly any other data structure. The power of LINQ lies in the fact that it is managed code that lets you write SQL type code to fetch data.  Whenever working with data we always need a way to filter out the data based on different condition. In this post we will look at some of the different ways in which we can filter data in LINQ with the help of where clause. Simple Filter for an array. Let’s say we have an array of number and we want to filter out data based on some condition. Below is an example int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 }; var lowNums =                 from num in numbers                 where num < 5                 select num;   Filter based on one of the property in the class. With the help of LINQ we can also filer out data from a list based on value of some property. var soldOutProducts =                 from prod in products                 where prod.UnitsInStock == 0                 select prod; Filter based on Multiple of the property in the class. var expensiveInStockProducts =         from prod in products         where prod.UnitsInStock > 0 && prod.UnitPrice > 3.00M         select prod; Filter based on the index of the Item in the list.In the below example we can see that we are able to filter data based on the index of the item in the list. string[] digits = { "zero", "one", "two", "three", "four", "five", "six"}; var shortDigits = digits.Where((digit, index) => digit.Length < index); There are many other way in which we can filter out data in LINQ. In the above post I have tried and shown few ways using the LINQ. Vikram

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• Why your Netapp is so slow...

  - by Darius Zanganeh

  Have you ever wondered why your Netapp FAS box is slow and doesn't perform well at large block workloads?  In this blog entry I will give you a little bit of information that will probably help you understand why it’s so slow, why you shouldn't use it for applications that read and write in large blocks like 64k, 128k, 256k ++ etc..  Of course since I work for Oracle at this time, I will show you why the ZS3 storage boxes are excellent choices for these types of workloads. Netapp’s Fundamental Problem The fundamental problem you have running these workloads on Netapp is the backend block size of their WAFL file system.  Every application block on a Netapp FAS ends up in a 4k chunk on a disk. Reference:  Netapp TR-3001 Whitepaper Netapp has proven this lacking large block performance fact in at least two different ways. They have NEVER posted an SPC-2 Benchmark yet they have posted SPC-1 and SPECSFS, both recently. In 2011 they purchased Engenio to try and fill this GAP in their portfolio. Block Size Matters So why does block size matter anyways?  Many applications use large block chunks of data especially in the Big Data movement.  Some examples are SAS Business Analytics, Microsoft SQL, Hadoop HDFS is even 64MB! Now let me boil this down for you.  If an application such MS SQL is writing data in a 64k chunk then before Netapp actually writes it on disk it will have to split it into 16 different 4k writes and 16 different disk IOPS.  When the application later goes to read that 64k chunk the Netapp will have to again do 16 different disk IOPS.  In comparison the ZS3 Storage Appliance can write in variable block sizes ranging from 512b to 1MB.  So if you put the same MSSQL database on a ZS3 you can set the specific LUNs for this database to 64k and then when you do an application read/write it requires only a single disk IO.  That is 16x faster!  But, back to the problem with your Netapp, you will VERY quickly run out of disk IO and hit a wall.  Now all arrays will have some fancy pre fetch algorithm and some nice cache and maybe even flash based cache such as a PAM card in your Netapp but with large block workloads you will usually blow through the cache and still need significant disk IO.  Also because these datasets are usually very large and usually not dedupable they are usually not good candidates for an all flash system.  You can do some simple math in excel and very quickly you will see why it matters.  Here are a couple of READ examples using SAS and MSSQL.  Assume these are the READ IOPS the application needs even after all the fancy cache and algorithms.   Here is an example with 128k blocks.  Notice the numbers of drives on the Netapp! Here is an example with 64k blocks You can easily see that the Oracle ZS3 can do dramatically more work with dramatically less drives.  This doesn't even take into account that the ONTAP system will likely run out of CPU way before you get to these drive numbers so you be buying many more controllers.  So with all that said, lets look at the ZS3 and why you should consider it for any workload your running on Netapp today.  ZS3 World Record Price/Performance in the SPC-2 benchmark ZS3-2 is #1 in Price Performance $12.08ZS3-2 is #3 in Overall Performance 16,212 MBPS Note: The number one overall spot in the world is held by an AFA 33,477 MBPS but at a Price Performance of $29.79.  A customer could purchase 2 x ZS3-2 systems in the benchmark with relatively the same performance and walk away with $600,000 in their pocket.

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• Solving Euler Project Problem Number 1 with Microsoft Axum

  - by Jeff Ferguson

  Note: The code below applies to version 0.3 of Microsoft Axum. If you are not using this version of Axum, then your code may differ from that shown here. I have just solved Problem 1 of Project Euler using Microsoft Axum. The problem statement is as follows: If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. My Axum-based solution is as follows: namespace EulerProjectProblem1{ // http://projecteuler.net/index.php?section=problems&id=1 // // If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. // The sum of these multiples is 23. // Find the sum of all the multiples of 3 or 5 below 1000. channel SumOfMultiples { input int Multiple1; input int Multiple2; input int UpperBound; output int Sum; } agent SumOfMultiplesAgent : channel SumOfMultiples { public SumOfMultiplesAgent() { int Multiple1 = receive(PrimaryChannel::Multiple1); int Multiple2 = receive(PrimaryChannel::Multiple2); int UpperBound = receive(PrimaryChannel::UpperBound); int Sum = 0; for(int Index = 1; Index < UpperBound; Index++) { if((Index % Multiple1 == 0) || (Index % Multiple2 == 0)) Sum += Index; } PrimaryChannel::Sum <-- Sum; } } agent MainAgent : channel Microsoft.Axum.Application { public MainAgent() { var SumOfMultiples = SumOfMultiplesAgent.CreateInNewDomain(); SumOfMultiples::Multiple1 <-- 3; SumOfMultiples::Multiple2 <-- 5; SumOfMultiples::UpperBound <-- 1000; var Sum = receive(SumOfMultiples::Sum); System.Console.WriteLine(Sum); System.Console.ReadLine(); PrimaryChannel::ExitCode <-- 0; } }} Let’s take a look at the various parts of the code. I begin by setting up a channel called SumOfMultiples that accepts three inputs and one output. The first two of the three inputs will represent the two possible multiples, which are three and five in this case. The third input will represent the upper bound of the problem scope, which is 1000 in this case. The lone output of the channel represents the sum of all of the matching multiples: channel SumOfMultiples{ input int Multiple1; input int Multiple2; input int UpperBound; output int Sum;} I then set up an agent that uses the channel. The agent, called SumOfMultiplesAgent, received the three inputs from the channel sent to the agent, stores the results in local variables, and performs the for loop that iterates from 1 to the received upper bound. The agent keeps track of the sum in a local variable and stores the sum in the output portion of the channel: agent SumOfMultiplesAgent : channel SumOfMultiples{ public SumOfMultiplesAgent() { int Multiple1 = receive(PrimaryChannel::Multiple1); int Multiple2 = receive(PrimaryChannel::Multiple2); int UpperBound = receive(PrimaryChannel::UpperBound); int Sum = 0; for(int Index = 1; Index < UpperBound; Index++) { if((Index % Multiple1 == 0) || (Index % Multiple2 == 0)) Sum += Index; } PrimaryChannel::Sum <-- Sum; }} The application’s main agent, therefore, simply creates a new SumOfMultiplesAgent in a new domain, prepares the channel with the inputs that we need, and then receives the Sum from the output portion of the channel: agent MainAgent : channel Microsoft.Axum.Application{ public MainAgent() { var SumOfMultiples = SumOfMultiplesAgent.CreateInNewDomain(); SumOfMultiples::Multiple1 <-- 3; SumOfMultiples::Multiple2 <-- 5; SumOfMultiples::UpperBound <-- 1000; var Sum = receive(SumOfMultiples::Sum); System.Console.WriteLine(Sum); System.Console.ReadLine(); PrimaryChannel::ExitCode <-- 0; }} The result of the calculation (which, by the way, is 233,168) is sent to the console using good ol’ Console.WriteLine().

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• Is your Credit Card Number valid?

  - by Rekha

  The credit card numbers may look like some random unique 16 digits number but those digits inform more than what we think it could be. The first digit of the card is the Major Industry Identifier: 1 and 2 -  Airlines 3  – Travel and Entertainment 4 and 5 -  Banking and Financial 6 – Merchandizing and Banking 7 – Petroleum 8 – Telecommunications 9 – National assignment The first 6 digits represent the Issuer Identification Number: Visa – 4xxxxx Master Card – 51xxxx & 55xxxx The 7th and following digits, excluding the last digit, are the person’s account number which leads to trillion possible combinations if the maximum of 12 digits is used. Many cards only use 9 digits. The final digit is the checksum or check digit. It is used to validate the card number using Luhn algorithm. How To Validate Credit Card Number? Take any credit card number, for example 5588 3201 2345 6789. Step 1: Double every other digit from the right: 5*2      8*2      3*2      0*2      2*2      4*2      6*2      8*2 ————————————————————————- 10        16        6          0          4          8      12        16 Step 2: Add these new digits to undoubled digits. All double digit numbers are added as a sum of their digits, so 16 becomes 1+6 = 7: Undoubled digits:       5          8          2          1          3          5          7          9 Doubled Digits:          10       16         6          0          4          8         12         16 Sum:  5+1+0+8+1+6+2+6+1+0+3+4+5+8+7+1+2+9+1+6 = 76 If the final sum is divisible by 10, then the Credit Card number is valid, if not, the number is invalid or fake!!! Hence the example is a fake number? via mint  cc and image credit This article titled,Is your Credit Card Number valid?, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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

  - by pjohnson

  I've started using Windows Workflow Foundation, and so far ran into a few things that aren't incredibly obvious. Microsoft did a good job of providing a ton of samples, which is handy because you need them to get anywhere with WF. The docs are thin, so I've been bouncing between samples and downloadable labs to figure out how to implement various activities in a workflow. Code separation or not? You can create a workflow and activity in Visual Studio with or without code separation, i.e. just a .cs "Component" style object with a Designer.cs file, or a .xoml XML markup file with code behind (beside?) it. Absence any obvious advantage to one or the other, I used code separation for workflows and any complex custom activities, and without code separation for custom activities that just inherit from the Activity class and thus don't have anything special in the designer. So far, so good. Service - In the WF world, this is simply a class that talks to the workflow about things outside the workflow, not to be confused with how the term "service" is used in every other context I've seen in the Windows and .NET world, i.e. an executable that waits for events or requests from a client and services them (Windows service, web service, WCF service, etc.). ListenActivity - Such a great concept, yet so unintuitive. It seems you need at least two branches (EventDrivenActivity instances), one for your positive condition and one for a timeout. The positive condition has a HandleExternalEventActivity, and the timeout has a DelayActivity followed by however you want to handle the delay, e.g. a ThrowActivity. The timeout is simple enough; wiring up the HandleExternalEventActivity is where things get fun. You need to create a service (see above), and an interface for that service (this seems more complex than should be necessary--why not have activities just wire to a service directly?). And you need to create a custom EventArgs class that inherits from ExternalDataEventArgs--you can't create an ExternalDataEventArgs event handler directly, even if you don't need to add any more information to the event args, despite ExternalDataEventArgs not being marked as an abstract class, nor a compiler error nor warning nor any other indication that you're doing something wrong, until you run it and find that it always times out and get to check every place mentioned here to see why. Your interface and service need an event that consumes your custom EventArgs class, and a method to fire that event. You need to call that method from somewhere. Then you get to hope that you did everything just right, or that you can step through code in the debugger before your Delay timeout expires. Yes, it's as much fun as it sounds. TransactionScopeActivity - I had the bright idea of putting one in as a placeholder, then filling in the database updates later. That caused this error: The workflow hosting environment does not have a persistence service as required by an operation on the workflow instance "[GUID]". ...which is about as helpful as "Object reference not set to an instance of an object" and even more fun to debug. Google led me to this Microsoft Forums hit, and from there I figured out it didn't like that the activity had no children. Again, a Validator on TransactionScopeActivity would have pointed this out to me at design time, rather than handing me a nearly useless error at runtime. Easily enough, I disabled the activity and that fixed it. I still see huge potential in my work where WF could make things easier and more flexible, but there are some seriously rough edges at the moment. Maybe I'm just spoiled by how much easier and more intuitive development elsewhere in the .NET Framework is.

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• Technology vs. Antiquated Methods

  - by AreYouSerious

  So Here I am talking with my Program lead, about technology, and how while my father is the VP of a major company, he still doesn't have a blackberry, or a smart phone. and I think it's funny. Most people would say it's a generational thing. That because he's older, he dosen't accept technology, and that's why. I have trouble swallowing that because this is the same man, who bought a satellite radio for his car, and made sure that the printer for the house was networked so that his and my mom's laptop could print wirelessly from the living room through their wireless network. I think it has to do with more with necessity, and partially with finical responsibility. My father is very financially conciencious. Think about it yourself. you pay for internet at your home. You have internet access at your office. But if you get a smart phone you're going to pay almost the same amount just for that access. A lot of people take it as just another fixed cost... I'm one of those. I don't even think about it, as I check my facebook from the bus, train, or even while sitting in traffic... The convience of having connection everywhere outweigh the financial responsible person screaming at in the back of my mind. However This conversation lead us to another venue of discussion.... what happens when the power dies. if you left your charger at home, or you phone or navi just stops working... are you going to be able to continue on as you did when it was working... let take the navi as an example... if your navi stops working, how many of you know how to use a map, and navigate? can you even find where you are on a map using the cross streets that your stopped at? This is a skill that unfortunatelly is overlooked these days in the child rearing process. Most people don't see the value, while some others can't do it themselves, so how can they teach their offspring? Take another example.... what if your phone gets lost... or stolen, or you drive over it? do you have the numbers in their memorized? are they recorded somewhere? I know that if it weren't for google sync I wouldn't have them backed up... not sufficiently. And what good does that do if you're in timbuckto and your phone dies, think you can get on the internet to look up those numbers? Don't get me wrong. I'm the first to see the value in technology, and am willing to pay the price to not have to wait for prices to come down. I will pay extra to have that newest thing right now. but let me tell you what.... I know that should I ever procreate it will be a requirement for my offspring (children) to learn how to do something manually before I'll let them use technology. Food for thought?? Let everyone else know what you think.... just sayin'

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• Are there too many qualified software development engineers chasing too few jobs?

  - by T Gregory

  I am trying to write this question in a non-argumentative way, but it is quite emotionally charged for some, so please bear with me. In the U.S., we hear constantly from CEOs that they cannot find enough qualified software engineers. In fact, it is the position of the U.S. government that demand for software engineering talent outpaces supply. This position can be clearly seen in the granting of tens of thousands of H1B visas, but also in the following excerpt from the official 2010-11 Bureau of Labor Statistics Occupational Outlook Handbook: Employment of computer software engineers is expected to increase by 32 percent from 2008-2018, which is much faster than the average for all occupations. In addition, this occupation will see a large number of new jobs, with more than 295,000 created between 2008 and 2018. Demand for computer software engineers will increase as computer networking continues to grow. For example, expanding Internet technologies have spurred demand for computer software engineers who can develop Internet, intranet, and World Wide Web applications. Likewise, electronic data-processing systems in business, telecommunications, healthcare, government, and other settings continue to become more sophisticated and complex. Implementing, safeguarding, and updating computer systems and resolving problems will fuel the demand for growing numbers of systems software engineers. New growth areas will also continue to arise from rapidly evolving technologies. The increasing uses of the Internet, the proliferation of Web sites, and mobile technology such as the wireless Internet have created a demand for a wide variety of new products. As more software is offered over the Internet, and as businesses demand customized software to meet their specific needs, applications and systems software engineers will be needed in greater numbers. In addition, the growing use of handheld computers will create demand for new mobile applications and software systems. As these devices become a larger part of the business environment, it will be necessary to integrate current computer systems with this new, more mobile technology. However, from the the employee side of the equation, we often hear the opposite. Many of the stories of SDEs with graduate degrees and decades of experience on the unemployment line, or the big tech interview war stories, are anecdotal, for sure. But, there is one piece of data that is neither anecdotal nor transitory, and that is the aggregate decisions of millions of undergraduates of what degree to pursue. Here, a different picture emerges from the data, and that picture is not good for the software profession. According the most recent Taulbee Survey from Computer Research Association, undergrad degree production in CS and CE has fallen nearly 60% since 2004. (Undergrad enrollments have ticked up in the past two years, but only modestly). Here we see that a basic disconnect between what corporate CEOs and the US government are saying and what potential employees really think about job prospects in software engineering. So my questions are these. Who are we to believe? Is there an acute talent shortage, or is there a long-term structural oversupply in the SDE labor market? Can anyone provide reliable data on long-term unemployment among SDEs? How many are leaving the profession due to lack of work? Real data is most helpful. Thanks.

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• Measuring Code Quality

  - by DotNetBlues

  Several months back, I was tasked with measuring the quality of code in my organization. Foolishly, I said, "No problem." I figured that Visual Studio has a built-in code metrics tool (Analyze -> Calculate Code Metrics) and that would be a fine place to start with. I was right, but also very wrong. The Visual Studio calculates five primary metrics: Maintainability Index, Cyclomatic Complexity, Depth of Inheritance, Class Coupling, and Lines of Code. The first two are figured at the method level, the second at (primarily) the class level, and the last is a simple count. The first question any reasonable person should ask is "Which one do I look at first?" The first question any manager is going to ask is, "What one number tells me about the whole application?" My answer to both, in a way, was "Maintainability Index." Why? Because each of the other numbers represent one element of quality while MI is a composite number that includes Cyclomatic Complexity. I'd be lying if I said no consideration was given to the fact that it was abstract enough that it's harder for some surly developer (I've been known to resemble that remark) to start arguing why a high coupling or inheritance is no big deal or how complex requirements are to blame for complex code. I should also note that I don't think there is one magic bullet metric that will tell you objectively how good a code base is. There are a ton of different metrics out there, and each one was created for a specific purpose in mind and has a pet theory behind it. When you've got a group of developers who aren't accustomed to measuring code quality, picking a 0-100 scale, non-controversial metric that can be easily generated by tools you already own really isn't a bad place to start. That sort of answers the question a developer would ask, but what about the management question; how do you dashboard this stuff when Visual Studio doesn't roll up the numbers to the solution level? Since VS does roll up the MI to the project level, I thought I could just figure out what sort of weighting Microsoft used to roll method scores up to the class level and then to the namespace and project levels. I was a bit surprised by the answer: there is no weighting. That means that a class with one 1300 line method (which will score a 0 MI) and one empty constructor (which will score a 100 MI) will have an overall MI of a respectable 50. Throw in a couple of DTOs that are nothing more than getters and setters (which tend to score 95 or better) and the project ends up looking really, really healthy. The next poor bastard who has to work on the application is probably not going to be singing the praises of its maintainability, though. For the record, that 1300 line method isn't a hypothetical, either. So, what does one do with that? Well, I decided to weight the average by the Lines of Code per method. For our above example, the formula for the class's MI becomes ((1300 * 0) + (1 * 100))/1301 = .077, rounded to 0. Sounds about right. Continue the pattern for namespace, project, solution, and even multi-solution application MI scores. This can be done relatively easily by using the "export to Excel" button and running a quick formula against the data. On the short list of follow-up questions would be, "How do I improve my application's score?" That's an answer for another time, though.

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• F1 Pit Pragmatics

  - by mikef

  "I hate computers. No, really, I hate them. I love the communications they facilitate, I love the conveniences they provide to my life. but I actually hate the computers themselves." - Scott Merrill, 'I hate computers: confessions of a Sysadmin' If Scott's goal was to polarize opinion and trigger raging arguments over the 'real reasons why computers suck', then he certainly succeeded. Impassioned vitriol sits side-by-side with rational debate. Yet Scott's fundamental point is absolutely on the money - Computers are a means to an end. The IT industry is finally starting to put weight behind the notion that good User Experience is an absolutely crucial goal, a cause championed by the likes of Microsoft's Bill Buxton, and which Apple's increasingly ubiquitous touch screen interface exemplifies. However, that doesn't change the fact that, occasionally, you just have to man up and deal with complex systems. In fact, sometimes you just need to sacrifice everything else in the name of performance. You'll find a perfect example of this Faustian bargain in Trevor Clarke's fascinating look into the (diabolical) IT infrastructure of modern F1 racing - high performance, high availability. high everything. To paraphrase, each car has up to 100 sensors, transmitting around 30Gb of data over the course of a race (70% in real-time). This data is then processed by no less than 3 servers (per car) so that the engineers in the pit have access to telemetry, strategy information, timing feeds, a connection back to the operations room in the team's home base - the list goes on. All of this while the servers are exposed "to carbon dust, oil, vibration, rain, heat, [and] variable power". Now, this is admittedly an extreme context where there's no real choice but to use complex systems where ease-of-use is, at best, a secondary concern. The flip-side is seen in small-scale personal computing such as that seen in Apple's iDevices, which are incredibly intuitive but limited in their scope. In terms of what kinds of systems they prefer to use, I suspect that most SysAdmins find themselves somewhere along this axis of Power vs. Usability, and which end of this axis you resonate with also hints at where you think the IT industry should focus its energy. Do you see yourself in the F1 pit, making split-second decisions, wrestling with information flows and reticent hardware to bend them to your will? If so, I imagine you feel that computers are subtle tools which need to be tuned and honed, using the advanced knowledge possessed only by responsible SysAdmins (If you have an iPhone, I suspect it's jail-broken). If the machines throw enigmatic errors, it's the price of flexibility and raw power. Alternatively, would you prefer to have your role more accessible, with users empowered by knowledge, spreading the load of managing IT environments? In that case, then you want hardware and software to have User Experience as their primary focus, and are of the "means to an end" school of thought (you're probably also fed up with users not listening to you when you try and help). At its heart, the dichotomy is between raw power (which might be difficult to use) and ease-of-use (which might have some limitations, but you can be up and running immediately). Of course, the ultimate goal is a fusion of flexibility, power and usability all in one system. It's achievable in specific software environments, and Red Gate considers it a target worth aiming for, but in other cases it's a goal right up there with cold fusion. I think it'll be a long time before we see it become ubiquitous. In the meantime, are you Power-Hungry or a Champion of Usability? Cheers, Michael Francis Simple Talk SysAdmin Editor

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• ArchBeat Link-o-Rama Top 10 for November 4-10, 2012

  - by Bob Rhubart

  The Top 10 most popular items shared via the OTN ArchBeat Facebook Page for the week of November 4-10, 2012. OAM/OVD JVM Tuning | @FusionSecExpert Vinay from the Oracle Fusion Middleware Architecture Group (the very prolific A-Team) shares a process for analyzing and improving performance in Oracle Virtual Directory and Oracle Access Manager. Exploring Lambda Expressions for the Java Language and the JVM | Java Magazine In the latest //Java/Architect column in Java Magazine, Ben Evans, Martijn Verburg, and Trisha Gee explain how, "although Lambda expressions might seem unfamiliar to begin with, they're quite easy to pick up, and mastering them will be vital for writing applications that can take full advantage of modern multicore CPUs." SOA Galore: New Books for Technical Eyes Only Shake up up your technical skills with this trio of new technical books from community members covering SOA and BPM. Oracle Solaris 11.1 update focuses on database integration, cloud | Mark Fontecchio TechTarget editor Mark Fontecchio reports on the recent Oracle Solaris 11.1 release, with comments from IDC's Al Gillen. Solving Big Problems in Our 21st Century Information Society | Irving Wladawsky-Berger "I believe that the kind of extensive collaboration between the private sector, academia and government represented by the Internet revolution will be the way we will generally tackle big problems in the 21st century. Just as with the Internet, governments have a major role to play as the catalyst for many of the big projects that the private sector will then take forward and exploit. The need for high bandwidth, robust national broadband infrastructures is but one such example." — Irving Wladawsky-Berger ADF Mobile Custom Javasciprt – iFrame Injection | John Brunswick The ADF Mobile Framework provides a range of out of the box components to add within your AMX pages, according to John Brunswick. But what happens when "an out of the box component does not directly fulfill your development need? What options are available to extend your application interface?" John has an answer. Architects Matter: Making sense of the people who make sense of enterprise IT Why do architects matter? Oracle Enterprise Architect Eric Stephens suggests that you ask yourself this question the next time you take the elevator to the Oracle offices on the 45th floor of the Willis Tower in Chicago, Illinois (or any other skyscraper, for that matter). If you had to take the stairs to get to those offices, who would you blame? "You get the picture," he says. "Architecture is essential for any necessarily complex structure, be it a building or an enterprise." (Read the article...) Converting SSL certificate generated by a 3rd party to an Oracle Wallet | Paulo Albuquerque Oracle Fusion Middleware A-Team member Paulo Albuquerque shares "a workaround to get your private key, certificate and CA trusted certificates chain into Oracle Wallet." How Data and BPM are married to get the right information to the right people at the right time | Leon Smiers "Business Process Management…supports a large group of stakeholders within an organization, all with different needs," says Oracle ACE Leon Smiers. "End-to-end processes typically run across departments, stakeholders and applications, and can often have a long life-span. So how do organizations provide all stakeholders with the information they need?" Leon provides answers in this post. Updated Business Activity Monitoring (BAM) Class | Gary Barg Oracle SOA Team blogger Gary Barg has news for those interested in a skills upgrade. This updated Oracle University course "explains how to use Oracle BAM to monitor enterprise business activities across an enterprise in real time. You can measure your key performance indicators (KPIs), determine whether you are meeting service-level agreements (SLAs), and take corrective action in real time." Thought for the Day "For every complex problem, there is a solution that is simple, neat, and wrong." — H. L. Mencken (September 12, 1880 – January 29, 1956) Source: SoftwareQuotes.com

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