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• CodePlex Daily Summary for Sunday, May 16, 2010

  CodePlex Daily Summary for Sunday, May 16, 2010New Projects3D Calculator: 3D Calc is a simple calculator application for Windows Phone 7, the purpose of this project is to demo the 3D animations capabilities of WP7 and sh...azaleas: AzaleasBlueset Studio Opensource Projects: Only for Opensource projects form Blueset Studio.Breck: A Phoenix and Jumper Moneky Production: Breck is a first person non-violent shooter developed in C++ and Dark GDK. After the main game is developed we are looking into making a sequel or...Discuz! Forum SDK: This project is use to login in and post or reply topic on discuz forum.Dominion.NET: Evolving Dominion source code originally written in VB6 and posted by "jatill" on Collectible Card Game Headquarters. Migration of the design and s...EkspSys2010-ITR: A mini project for the course Experimental System devolopment in spring 2010Facebook Graph Toolkit: This project is a .Net implementation of the Facebook Graph API. The aim of this project is to be a replacement to the existing Facebook Toolkit (h...iFree: This is a solution for Vietnamese network socialInfoPath Editor for Developer: InfoPath Editor for developer allows user to modify the html text directly inside InfoPath designer or filler and push the change back to InfoPath ...iZeit: Run your own online calendar, with blog integration, recurrence, todo list and categories.machgos dotNet Tests: Just some little test-projects for learningmim: TBAMinePost: MinePost is a game made for the first 48 hour Reddit Game Jam.Mockina: Mockina is a mock framework. Expression tree syntax is used to specify which members to mock, both public and non-public. The code is easy to under...MSBuild Launch Pad (mPad): This is just another shell extension for MSBuild to enable quick execution of MSBuild scripts via Windows Explorer context menu. (C) 2010 Lex LiPeacock: A browser like tabbed applicationPrimeCalculation: PrimeCalculation is a .NET app to calculate primes in a given range. Speed on Core2Duo 2,4GHZ: Found all primes from 0 to 1 billion in 35 seconds (...Slightly Silverlight: A Framework that leverages Silverlight for processing, business logic but standard HTML for the presentation layer.Stopwatch: Stopwatch is a tool for measuring the time. To start and pause stopwatch you only need to press a key on the keyboard. An additional context menu a...YAXLib: Yet Another XML Serialization Library for the .NET Framework: YAXLib is an XML Serialization library which helps you structure freely the XML result, choose among private and public fields to be serialized, an...New ReleasesActivate Your Glutes: v1.0.3.0: This release is a migration to VS2010, .Net 4, MVC2 and Entity Framework 4. The code has also been considerably cleaned up - taking advantage of E...AnyCAD: AnyCAD.Free.ENU.v1.1: http://www.anycad.net Modeling •2D: Line, Rectangle, Arc, Arch, Circle, Spline, Polygon •Feature: Extrude, Loft, Chamfer, Sweep, Revol •Boolean: ...Blueset Studio Opensource Projects: 多功能计算器 3.5: 稳定版本。Code for Rapid C# Windows Development eBook: LLBLGen LINQPad Data Context Driver Ver 1.0.0.0: First release of a Static LLBLGen Pro Data Context Driver for LINQPad I recommend LINQPad 4 as it seems more stable with this driver than LINQPad 2.DSQLT - Dynamic SQL Templates: Release 1.2. Some behaviour has changed!!: Attention. Some behaviour has changed! Now its necessary to use WildCards in the pattern-parameter for DSQLT.AllSourceContains DSQLT.Databases DSQ...FDS AutoCAD plug-in: FDS to AutoCAD plug-in: Basic functionality was implemented. Some routines like setting fds executable location are still not automated.Feature Builder Guidance Extensions: FBGX 2 - Standalone FX: Background: The Feature Builder Guidance is extensible and displays guidance content supplied by all the Feature Builder Guidance Extensions (FBGX...Floe IRC Client: Floe IRC Client 2010-05 R3: - You can now right click on the input box to get options for toggling bold, underline, colors, etc. - The size of the nickname column is now saved...Floe IRC Client: Floe IRC Client 2010-05 R4: - A user's channel status now appears next to their nick when they talk (e.g. @Nick or +Nick) - Fixed an error where certain kinds of network probl...HD-Trailers.NET Downloader: HD-Trailers.NET Downloader v1.0: Version 1.0 Thanks to Wolfgang for all his help. I let this project languish for too long while focusing on other things, but his involvement has ...InfoPath Editor for Developer: InfoPath Editor Beta 1: Intial Release: Can load InfoPath inner html. Can edit InfoPath inner html. InfoPath 2007 only.LinkSharp: LinkSharp 0.1.0: First release of LinkSharp. Set up iis, and use the sql script to create a new database.PowerAuras: PowerAuras V3.0.0F: This version adds better integration with GTFO New Flags Added PvP flag In 5-Man Instance In Raid Instance In Battleground In ArenaRx Contrib: V1.4: Add the ability to catch internal exception and the ability to publish error by queue adaptersSEO SiteMap: SEO SiteMap RC1: -SevenZipLib Library: v9.13.2: Stable release associated with 7z.dll 9.13 beta. Ability to create and update archives not implemente yet.Silverlight / WPF Controls: Upload, FlipPanel, DeepZoom, Animation, Encryption: Code Camp Demonstration: This code example demonstrates MVVM/MEF with WPF with attached properties,security and custom ICommand class.SQL Data Capture - Black Box Application Testing: SQLDataCapture V1.2: Added Entity Framework Support to CRUD generator (Insert Stored Procedure) and switched to VS 2010 for development.Stopwatch: Stopwatch 0.1: Stopwatch Release 0.1VCC: Latest build, v2.1.30515.0: Automatic drop of latest buildYet another developer blog - Examples: Asynchronous TreeView in ASP.NET MVC: This sample application shows how to use jQuery TreeView plugin for creating an asynchronous TreeView in ASP.NET MVC. This application is accompani...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryRawrPHPExcelBlogEngine.NETMicrosoft Biology FoundationCustomer Portal Accelerator for Microsoft Dynamics CRMWindows Azure Command-line Tools for PHP DevelopersMirror Testing SystemN2 CMSStyleCop

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• Parallel LINQ - PLINQ

  - by nmarun

  Turns out now with .net 4.0 we can run a query like a multi-threaded application. Say you want to query a collection of objects and return only those that meet certain conditions. Until now, we basically had one ‘control’ that iterated over all the objects in the collection, checked the condition on each object and returned if it passed. We obviously agree that if we can ‘break’ this task into smaller ones, assign each task to a different ‘control’ and ask all the controls to do their job - in-parallel, the time taken the finish the entire task will be much lower. Welcome to PLINQ. Let’s take some examples. I have the following method that uses our good ol’ LINQ. 1: private static void Linq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers =   from num in source 12: where IsDivisibleBy(num, 2) 13: select num; 14: 15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } I’ve added comments for the major steps, but the only thing I want to talk about here is the IsDivisibleBy() method. I know I could have just included the logic directly in the where clause. I called a method to add ‘delay’ to the execution of the query - to simulate a loooooooooong operation (will be easier to compare the results). 1: private static bool IsDivisibleBy(int number, int divisor) 2: { 3: // iterate over some database query 4: // to add time to the execution of this method; 5: // the TableB has around 10 records 6: for (int i = 0; i < 10; i++) 7: { 8: DataClasses1DataContext dataContext = new DataClasses1DataContext(); 9: var query = from b in dataContext.TableBs select b; 10: 11: foreach (var row in query) 12: { 13: // Do NOTHING (wish my job was like this) 14: } 15: } 16:  17: return number % divisor == 0; 18: } Now, let’s look at how to modify this to PLINQ. 1: private static void Plinq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers = from num in source.AsParallel() 12: where IsDivisibleBy(num, 2) 13: select num; 14:  15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } That’s it, this is now in PLINQ format. Oh and if you haven’t found the difference, look line 11 a little more closely. You’ll see an extension method ‘AsParallel()’ added to the ‘source’ variable. Couldn’t be more simpler right? So this is going to improve the performance for us. Let’s test it. So in my Main method of the Console application that I’m working on, I make a call to both. 1: static void Main(string[] args) 2: { 3: // set lower and upper limits 4: int lowerLimit = 1; 5: int upperLimit = 20; 6: // call the methods 7: Console.WriteLine("Calling Linq() method"); 8: Linq(lowerLimit, upperLimit); 9: 10: Console.WriteLine(); 11: Console.WriteLine("Calling Plinq() method"); 12: Plinq(lowerLimit, upperLimit); 13:  14: Console.ReadLine(); // just so I get enough time to read the output 15: } YMMV, but here are the results that I got:    It’s quite obvious from the above results that the Plinq() method is taking considerably less time than the Linq() version. I’m sure you’ve already noticed that the output of the Plinq() method is not in order. That’s because, each of the ‘control’s we sent to fetch the results, reported with values as and when they obtained them. This is something about parallel LINQ that one needs to remember – the collection cannot be guaranteed to be undisturbed. This could be counted as a negative about PLINQ (emphasize ‘could’). Nevertheless, if we want the collection to be sorted, we can use a SortedSet (.net 4.0) or build our own custom ‘sorter’. Either way we go, there’s a good chance we’ll end up with a better performance using PLINQ. And there’s another negative of PLINQ (depending on how you see it). This is regarding the CPU cycles. See the usage for Linq() method (used ResourceMonitor): I have dual CPU’s and see the height of the peak in the bottom two blocks and now compare to what happens when I run the Plinq() method. The difference is obvious. Higher usage, but for a shorter duration (width of the peak). Both these points make sense in both cases. Linq() runs for a longer time, but uses less resources whereas Plinq() runs for a shorter time and consumes more resources. Even after knowing all these, I’m still inclined towards PLINQ. PLINQ rocks! (no hard feelings LINQ)

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• DTracing a PHPUnit Test: Looking at Functional Programming

  - by cj

  Here's a quick example of using DTrace Dynamic Tracing to work out what a PHP code base does. I was reading the article Functional Programming in PHP by Patkos Csaba and wondering how efficient this stype of programming is. I thought this would be a good time to fire up DTrace and see what is going on. Since DTrace is "always available" even in production machines (once PHP is compiled with --enable-dtrace), this was easy to do. I have Oracle Linux with the UEK3 kernel and PHP 5.5 with DTrace static probes enabled, as described in DTrace PHP Using Oracle Linux 'playground' Pre-Built Packages I installed the Functional Programming sample code and Sebastian Bergmann's PHPUnit. Although PHPUnit is included in the Functional Programming example, I found it easier to separately download and use its phar file: cd ~/Desktop wget -O master.zip https://github.com/tutsplus/functional-programming-in-php/archive/master.zip wget https://phar.phpunit.de/phpunit.phar unzip master.zip I created a DTrace D script functree.d: #pragma D option quiet self int indent; BEGIN { topfunc = $1; } php$target:::function-entry /copyinstr(arg0) == topfunc/ { self->follow = 1; } php$target:::function-entry /self->follow/ { self->indent += 2; printf("%*s %s%s%s\n", self->indent, "->", arg3?copyinstr(arg3):"", arg4?copyinstr(arg4):"", copyinstr(arg0)); } php$target:::function-return /self->follow/ { printf("%*s %s%s%s\n", self->indent, "<-", arg3?copyinstr(arg3):"", arg4?copyinstr(arg4):"", copyinstr(arg0)); self->indent -= 2; } php$target:::function-return /copyinstr(arg0) == topfunc/ { self->follow = 0; } This prints a PHP script function call tree starting from a given PHP function name. This name is passed as a parameter to DTrace, and assigned to the variable topfunc when the DTrace script starts. With this D script, choose a PHP function that isn't recursive, or modify the script to set self->follow = 0 only when all calls to that function have unwound. From looking at the sample FunSets.php code and its PHPUnit test driver FunSetsTest.php, I settled on one test function to trace: function testUnionContainsAllElements() { ... } I invoked DTrace to trace function calls invoked by this test with # dtrace -s ./functree.d -c 'php phpunit.phar \ /home/cjones/Desktop/functional-programming-in-php-master/FunSets/Tests/FunSetsTest.php' \ '"testUnionContainsAllElements"' The core of this command is a call to PHP to run PHPUnit on the FunSetsTest.php script. Outside that, DTrace is called and the PID of PHP is passed to the D script $target variable so the probes fire just for this invocation of PHP. Note the quoting around the PHP function name passed to DTrace. The parameter must have double quotes included so DTrace knows it is a string. The output is: PHPUnit 3.7.28 by Sebastian Bergmann. ......-> FunSetsTest::testUnionContainsAllElements -> FunSets::singletonSet <- FunSets::singletonSet -> FunSets::singletonSet <- FunSets::singletonSet -> FunSets::union <- FunSets::union -> FunSets::contains -> FunSets::{closure} -> FunSets::contains -> FunSets::{closure} <- FunSets::{closure} <- FunSets::contains <- FunSets::{closure} <- FunSets::contains -> PHPUnit_Framework_Assert::assertTrue -> PHPUnit_Framework_Assert::isTrue <- PHPUnit_Framework_Assert::isTrue -> PHPUnit_Framework_Assert::assertThat -> PHPUnit_Framework_Constraint::count <- PHPUnit_Framework_Constraint::count -> PHPUnit_Framework_Constraint::evaluate -> PHPUnit_Framework_Constraint_IsTrue::matches <- PHPUnit_Framework_Constraint_IsTrue::matches <- PHPUnit_Framework_Constraint::evaluate <- PHPUnit_Framework_Assert::assertThat <- PHPUnit_Framework_Assert::assertTrue -> FunSets::contains -> FunSets::{closure} -> FunSets::contains -> FunSets::{closure} <- FunSets::{closure} <- FunSets::contains -> FunSets::contains -> FunSets::{closure} <- FunSets::{closure} <- FunSets::contains <- FunSets::{closure} <- FunSets::contains -> PHPUnit_Framework_Assert::assertTrue -> PHPUnit_Framework_Assert::isTrue <- PHPUnit_Framework_Assert::isTrue -> PHPUnit_Framework_Assert::assertThat -> PHPUnit_Framework_Constraint::count <- PHPUnit_Framework_Constraint::count -> PHPUnit_Framework_Constraint::evaluate -> PHPUnit_Framework_Constraint_IsTrue::matches <- PHPUnit_Framework_Constraint_IsTrue::matches <- PHPUnit_Framework_Constraint::evaluate <- PHPUnit_Framework_Assert::assertThat <- PHPUnit_Framework_Assert::assertTrue -> FunSets::contains -> FunSets::{closure} -> FunSets::contains -> FunSets::{closure} <- FunSets::{closure} <- FunSets::contains -> FunSets::contains -> FunSets::{closure} <- FunSets::{closure} <- FunSets::contains <- FunSets::{closure} <- FunSets::contains -> PHPUnit_Framework_Assert::assertFalse -> PHPUnit_Framework_Assert::isFalse -> {closure} -> main <- main <- {closure} <- PHPUnit_Framework_Assert::isFalse -> PHPUnit_Framework_Assert::assertThat -> PHPUnit_Framework_Constraint::count <- PHPUnit_Framework_Constraint::count -> PHPUnit_Framework_Constraint::evaluate -> PHPUnit_Framework_Constraint_IsFalse::matches <- PHPUnit_Framework_Constraint_IsFalse::matches <- PHPUnit_Framework_Constraint::evaluate <- PHPUnit_Framework_Assert::assertThat <- PHPUnit_Framework_Assert::assertFalse <- FunSetsTest::testUnionContainsAllElements ... Time: 1.85 seconds, Memory: 3.75Mb OK (9 tests, 23 assertions) The periods correspond to the successful tests before and after (and from) the test I was tracing. You can see the function entry ("->") and return ("<-") points. Cross checking with the testUnionContainsAllElements() source code confirms the two singletonSet() calls, one union() call, two assertTrue() calls and finally an assertFalse() call. These assertions have a contains() call as a parameter, so contains() is called before the PHPUnit assertion functions are run. You can see contains() being called recursively, and how the closures are invoked. If you want to focus on the application logic and suppress the PHPUnit function trace, you could turn off tracing when assertions are being checked by adding D clauses checking the entry and exit of assertFalse() and assertTrue(). But if you want to see all of PHPUnit's code flow, you can modify the functree.d code that sets and unsets self-follow, and instead change it to toggle the variable in request-startup and request-shutdown probes: php$target:::request-startup { self->follow = 1 } php$target:::request-shutdown { self->follow = 0 } Be prepared for a large amount of output!

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• Conversion of BizTalk Projects to Use the New WCF-SAP Adaptor

  - by Geordie

  We are in the process of upgrading our BizTalk Environment from BizTalk 2006 R2 to BizTalk 2010. The SAP adaptor in BizTalk 2010 is an all new and more powerful WCF-SAP adaptor. When my colleagues tested out the new adaptor they discovered that the format of the data extracted from SAP was not identical to the old adaptor. This is not a big deal if the structure of the messages from SAP is simple. In this case we were receiving the delivery and invoice iDocs. Both these structures are complex especially the delivery document. Over the past few years I have tweaked the delivery mapping to remove bugs from original mapping. The idea of redoing these maps did not appeal and due to the current work load was not even an option. I opted for a rather crude alternative of pulling in the iDoc in the new typed format and then adding a static map at the start of the orchestration to convert the data to the old schema.  Note WCF-SAP data formats (on the binding tab of the configuration dialog box is the ‘RecieiveIdocFormat’ field): Typed:  Returns a XML document with the hierarchy represented in XML and all fields being represented by XML tags. RFC: Returns an XML document with the hierarchy represented in XML but the iDoc lines in flat file format. String: This returns the iDoc in a format that is closest to the original flat file format but is still wrapped with some top level XML tags. The files also contained some strange characters at the end of each line. I started with the invoice document and it was quite straight forward to add the mapping but this is where my problems started. The orchestrations for these documents are dynamic and so require the identity of the partner to be able to correctly configure the orchestration. The partner identity is in the EDI_DC40 segment of the iDoc. In the old project the RECPRN node of the segment was promoted. The code to set a variable to the partner ID was now failing. After lot of head scratching I discovered the problem was due to the addition of Namespaces to the fields in the EDI_DC40 segment. To overcome this I needed to use an xPath query with a Namespace Manager. This had to be done in custom code. I now tried to repeat the process with the delivery document. Unfortunately when we tried to get sample typed data from SAP an exception was thrown. The adapter "WCF-SAP" raised an error message. Details "Microsoft.ServiceModel.Channels.Common.XmlReaderGenerationException: The segment or group definition E2EDKA1001 was not found in the IDoc metadata. The UniqueId of the IDoc type is: IDOCTYP/3/DESADV01/ZASNEXT1/640. For Receive operations, the SAP adapter does not support unreleased segments.   Our guess is that when the WCF-SAP adaptor tries to down load the data it retrieves a data schema from SAP. For some reason the schema does not match the data. This may be due to the version of SAP we are running or due to a customization. Either way resolving this problem did not look easy. When doing some research on this problem I found an article showing me how to get the data from SAP using the WCF-SAP adaptor without any XML tags. http://blogs.msdn.com/b/adapters/archive/2007/10/05/receiving-idocs-getting-the-raw-idoc-data.aspx Reproduction of Mustansir blog: Since the WCF based SAP Adapter is ... well, WCF based, all data flowing in and out of the adapter is encapsulated within a SOAP message. Which means there are those pesky xml tags all over the place. If you want to receive an Idoc from SAP, you can receive it in "Typed" format (in which case each column in each segment of the idoc appears within its own xml tag), or you can receive it in "String" format (in which case there are just 2 xml tags at the top, the raw xml data in string/flat file format, and the 2 closing xml tags). In "String" format, an incoming idoc (for ORDERS05, containing 5 data records) would look like: <ReceiveIdoc ><idocData>EDI_DC40 8000000000001064985620 E2EDK01005 800000000000106498500000100000001 E2EDK14 8000000000001064985000002000000020111000 E2EDK14 8000000000001064985000003000000020081000 E2EDK14 80000000000010649850000040000000200710 E2EDK14 80000000000010649850000050000000200600</idocData></ReceiveIdoc> (I have trimmed part of the control record so that it fits cleanly here on one line). Now, you're only interested in the IDOC data, and don't care much for the XML tags. It isn't that difficult to write your own pipeline component, or even some logic in the orchestration to remove the tags, right? Well, you don't need to write any extra code at all - the WCF Adapter can help you here! During the configuration of your one-way Receive Location using WCF-Custom, navigate to the Messages tab. Under the section "Inbound BizTalk Messge Body", select the "Path" radio button, and: (a) Enter the body path expression as: /*[local-name()='ReceiveIdoc']/*[local-name()='idocData'] (b) Choose "String" for the Node Encoding. What we've done is, used an XPATH to pull out the value of the "idocData" node from the XML. Your Receive Location will now emit text containing only the idoc data. You can at this point, for example, put the Flat File Pipeline component to convert the flat text into a different xml format based on some other schema you already have, and receive your version of the xml formatted message in your orchestration.   This was potentially a much easier solution than adding the static maps to the orchestrations and overcame the issue with ‘Typed’ delivery documents. Not quite so fast… Note: When I followed Mustansir’s blog the characters at the end of each line disappeared. After configuring the adaptor and passing the iDoc data into the original flat file receive pipelines I was receiving exceptions. There was a failure executing the receive pipeline: "PAPINETPipelines.DeliveryFlatFileReceive, CustomerIntegration2.PAPINET.Pipelines, Version=1.0.0.0, Culture=neutral, PublicKeyToken=4ca3635fbf092bbb" Source: "Pipeline " Receive Port: "recSAP_Delivery" URI: "D:\CustomerIntegration2\SAP\Delivery\*.xml" Reason: An error occurred when parsing the incoming document: "Unexpected data found while looking for: 'Z2EDPZ7' The current definition being parsed is E2EDP07GRP. The stream offset where the error occured is 8859. The line number where the error occured is 23. The column where the error occured is 0.". Although the new flat file looked the same as the old one there was a differences. In the original file all lines in the document were exactly 1064 character long. In the new file all lines were truncated to the last alphanumeric character. The final piece of the puzzle was to add a custom pipeline component to pad all the lines to 1064 characters. This component was added to the decode node of the custom delivery and invoice flat file disassembler pipelines. Execute method of the custom pipeline component: public IBaseMessage Execute(IPipelineContext pc, IBaseMessage inmsg) { //Convert Stream to a string Stream s = null; IBaseMessagePart bodyPart = inmsg.BodyPart;   // NOTE inmsg.BodyPart.Data is implemented only as a setter in the http adapter API and a //getter and setter for the file adapter. Use GetOriginalDataStream to get data instead. if (bodyPart != null) s = bodyPart.GetOriginalDataStream();   string newMsg = string.Empty; string strLine; try { StreamReader sr = new StreamReader(s); strLine = sr.ReadLine(); while (strLine != null) { //Execute padding code if (strLine != null) strLine = strLine.PadRight(1064, ' ') + "\r\n"; newMsg += strLine; strLine = sr.ReadLine(); } sr.Close(); } catch (IOException ex) { throw new Exception("Error occured trying to pad the message to 1064 charactors"); }   //Convert back to stream and set to Data property inmsg.BodyPart.Data = new MemoryStream(Encoding.UTF8.GetBytes(newMsg)); ; //reset the position of the stream to zero inmsg.BodyPart.Data.Position = 0; return inmsg; }

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• Combination of Operating Mode and Commit Strategy

  - by Kevin Yang

  If you want to populate a source into multiple targets, you may also want to ensure that every row from the source affects all targets uniformly (or separately). Let’s consider the Example Mapping below. If a row from SOURCE causes different changes in multiple targets (TARGET_1, TARGET_2 and TARGET_3), for example, it can be successfully inserted into TARGET_1 and TARGET_3, but failed to be inserted into TARGET_2, and the current Mapping Property TLO (target load order) is “TARGET_1 -> TARGET_2 -> TARGET_3”. What should Oracle Warehouse Builder do, in order to commit the appropriate data to all affected targets at the same time? If it doesn’t behave as you intended, the data could become inaccurate and possibly unusable.                                               Example Mapping In OWB, we can use Mapping Configuration Commit Strategies and Operating Modes together to achieve this kind of requirements. Below we will explore the combination of these two features and how they affect the results in the target tables Before going to the example, let’s review some of the terms we will be using (Details can be found in white paper Oracle® Warehouse Builder Data Modeling, ETL, and Data Quality Guide11g Release 2): Operating Modes: Set-Based Mode: Warehouse Builder generates a single SQL statement that processes all data and performs all operations. Row-Based Mode: Warehouse Builder generates statements that process data row by row. The select statement is in a SQL cursor. All subsequent statements are PL/SQL. Row-Based (Target Only) Mode: Warehouse Builder generates a cursor select statement and attempts to include as many operations as possible in the cursor. For each target, Warehouse Builder inserts each row into the target separately. Commit Strategies: Automatic: Warehouse Builder loads and then automatically commits data based on the mapping design. If the mapping has multiple targets, Warehouse Builder commits and rolls back each target separately and independently of other targets. Use the automatic commit when the consequences of multiple targets being loaded unequally are not great or are irrelevant. Automatic correlated: It is a specialized type of automatic commit that applies to PL/SQL mappings with multiple targets only. Warehouse Builder considers all targets collectively and commits or rolls back data uniformly across all targets. Use the correlated commit when it is important to ensure that every row in the source affects all affected targets uniformly. Manual: select manual commit control for PL/SQL mappings when you want to interject complex business logic, perform validations, or run other mappings before committing data. Combination of the commit strategy and operating mode To understand the effects of each combination of operating mode and commit strategy, I’ll illustrate using the following example Mapping. Firstly we insert 100 rows into the SOURCE table and make sure that the 99th row and 100th row have the same ID value. And then we create a unique key constraint on ID column for TARGET_2 table. So while running the example mapping, OWB tries to load all 100 rows to each of the targets. But the mapping should fail to load the 100th row to TARGET_2, because it will violate the unique key constraint of table TARGET_2. With different combinations of Commit Strategy and Operating Mode, here are the results ¦ Set-based/ Correlated Commit: Configuration of Example mapping:                                                     Result:                                                      What’s happening: A single error anywhere in the mapping triggers the rollback of all data. OWB encounters the error inserting into Target_2, it reports an error for the table and does not load the row. OWB rolls back all the rows inserted into Target_1 and does not attempt to load rows to Target_3. No rows are added to any of the target tables. ¦ Row-based/ Correlated Commit: Configuration of Example mapping:                                                   Result:                                                  What’s happening: OWB evaluates each row separately and loads it to all three targets. Loading continues in this way until OWB encounters an error loading row 100th to Target_2. OWB reports the error and does not load the row. It rolls back the row 100th previously inserted into Target_1 and does not attempt to load row 100 to Target_3. Then, if there are remaining rows, OWB will continue loading them, resuming with loading rows to Target_1. The mapping completes with 99 rows inserted into each target. ¦ Set-based/ Automatic Commit: Configuration of Example mapping: Result: What’s happening: When OWB encounters the error inserting into Target_2, it does not load any rows and reports an error for the table. It does, however, continue to insert rows into Target_3 and does not roll back the rows previously inserted into Target_1. The mapping completes with one error message for Target_2, no rows inserted into Target_2, and 100 rows inserted into Target_1 and Target_3 separately. ¦ Row-based/Automatic Commit: Configuration of Example mapping: Result: What’s happening: OWB evaluates each row separately for loading into the targets. Loading continues in this way until OWB encounters an error loading row 100 to Target_2 and reports the error. OWB does not roll back row 100th from Target_1, does insert it into Target_3. If there are remaining rows, it will continue to load them. The mapping completes with 99 rows inserted into Target_2 and 100 rows inserted into each of the other targets. Note: Automatic Correlated commit is not applicable for row-based (target only). If you design a mapping with the row-based (target only) and correlated commit combination, OWB runs the mapping but does not perform the correlated commit. In set-based mode, correlated commit may impact the size of your rollback segments. Space for rollback segments may be a concern when you merge data (insert/update or update/insert). Correlated commit operates transparently with PL/SQL bulk processing code. The correlated commit strategy is not available for mappings run in any mode that are configured for Partition Exchange Loading or that include a Queue, Match Merge, or Table Function operator. If you want to practice in your own environment, you can follow the steps: 1. Import the MDL file: commit_operating_mode.mdl 2. Fix the location for oracle module ORCL and deploy all tables under it. 3. Insert sample records into SOURCE table, using below plsql code: begin     for i in 1..99     loop         insert into source values(i, 'col_'||i);     end loop;     insert into source values(99, 'col_99'); end; 4. Configure MAPPING_1 to any combinations of operating mode and commit strategy you want to test. And make sure feature TLO of mapping is open. 5. Deploy Mapping “MAPPING_1”. 6. Run the mapping and check the result.

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• C#: LINQ vs foreach - Round 1.

  - by James Michael Hare

  So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

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• SQL SERVER – Weekly Series – Memory Lane – #052

  - by Pinal Dave

  Let us continue with the final episode of the Memory Lane Series. Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Set Server Level FILLFACTOR Using T-SQL Script Specifies a percentage that indicates how full the Database Engine should make the leaf level of each index page during index creation or alteration. fillfactor must be an integer value from 1 to 100. The default is 0. Limitation of Online Index Rebuld Operation Online operation means when online operations are happening in the database are in normal operational condition, the processes which are participating in online operations does not require exclusive access to the database. Get Permissions of My Username / Userlogin on Server / Database A few days ago, I was invited to one of the largest database company. I was asked to review database schema and propose changes to it. There was special username or user logic was created for me, so I can review their database. I was very much interested to know what kind of permissions I was assigned per server level and database level. I did not feel like asking Sr. DBA the question about permissions. Simple Example of WHILE Loop With CONTINUE and BREAK Keywords This question is one of those questions which is very simple and most of the users get it correct, however few users find it confusing for the first time. I have tried to explain the usage of simple WHILE loop in the first example. BREAK keyword will exit the stop the while loop and control is moved to the next statement after the while loop. CONTINUE keyword skips all the statement after its execution and control is sent to the first statement of while loop. Forced Parameterization and Simple Parameterization – T-SQL and SSMS When the PARAMETERIZATION option is set to FORCED, any literal value that appears in a SELECT, INSERT, UPDATE or DELETE statement is converted to a parameter during query compilation. When the PARAMETERIZATION database option is SET to SIMPLE, the SQL Server query optimizer may choose to parameterize the queries. 2008 Transaction and Local Variables – Swap Variables – Update All At Once Concept Summary : Transaction have no effect over memory variables. When UPDATE statement is applied over any table (physical or memory) all the updates are applied at one time together when the statement is committed. First of all I suggest that you read the article listed above about the effect of transaction on local variant. As seen there local variables are independent of any transaction effect. Simulate INNER JOIN using LEFT JOIN statement – Performance Analysis Just a day ago, while I was working with JOINs I find one interesting observation, which has prompted me to create following example. Before we continue further let me make very clear that INNER JOIN should be used where it cannot be used and simulating INNER JOIN using any other JOINs will degrade the performance. If there are scopes to convert any OUTER JOIN to INNER JOIN it should be done with priority. 2009 Introduction to Business Intelligence – Important Terms & Definitions Business intelligence (BI) is a broad category of application programs and technologies for gathering, storing, analyzing, and providing access to data from various data sources, thus providing enterprise users with reliable and timely information and analysis for improved decision making. Difference Between Candidate Keys and Primary Key Candidate Key – A Candidate Key can be any column or a combination of columns that can qualify as unique key in database. There can be multiple Candidate Keys in one table. Each Candidate Key can qualify as Primary Key. Primary Key – A Primary Key is a column or a combination of columns that uniquely identify a record. Only one Candidate Key can be Primary Key. 2010 Taking Multiple Backup of Database in Single Command – Mirrored Database Backup I recently had a very interesting experience. In one of my recent consultancy works, I was told by our client that they are going to take the backup of the database and will also a copy of it at the same time. I expressed that it was surely possible if they were going to use a mirror command. In addition, they told me that whenever they take two copies of the database, the size of the database, is always reduced. Now this was something not clear to me, I said it was not possible and so I asked them to show me the script. Corrupted Backup File and Unsuccessful Restore The CTO, who was also present at the location, got very upset with this situation. He then asked when the last successful restore test was done. As expected, the answer was NEVER.There were no successful restore tests done before. During that time, I was present and I could clearly see the stress, confusion, carelessness and anger around me. I did not appreciate the feeling and I was pretty sure that no one in there wanted the atmosphere like me. 2011 TRACEWRITE – Wait Type – Wait Related to Buffer and Resolution SQL Trace is a SQL Server database engine technology which monitors specific events generated when various actions occur in the database engine. When any event is fired it goes through various stages as well various routes. One of the routes is Trace I/O Provider, which sends data to its final destination either as a file or rowset. DATEDIFF – Accuracy of Various Dateparts If you want to have accuracy in seconds, you need to use a different approach. In the first example, the accurate method is to find the number of seconds first and then divide it by 60 to convert it in minutes. Dedicated Access Control for SQL Server Express Edition http://www.youtube.com/watch?v=1k00z82u4OI Book Signing at SQLPASS 2012 Who I Am And How I Got Here – True Story as Blog Post If there was a shortcut to success – I want to know. I learnt SQL Server hard way and I am still learning. There are so many things, I have to learn. There is not enough time to learn everything which we want to learn. I am constantly working on it every day. I welcome you to join my journey as well. Please join me in my journey to learn SQL Server – more the merrier. Vacation, Travel and Study – A New Concept Even those who have advanced degrees and went to college for years, or even decades, find studying hard.  There is a difference between studying for a career and studying for a certification.  At least to get a degree there is a variety of subjects, with labs, exams, and practice problems to make things more interesting. Order By Numeric Values Formatted as String We have a table which has a column containing alphanumeric data. The data always has first as an integer and later part as a string. The business need is to order the data based on the first part of the alphanumeric data which is an integer. Now the problem is that no matter how we use ORDER BY the result is not produced as expected. Let us understand this with an example. Resolving SQL Server Connection Errors – SQL in Sixty Seconds #030 – Video One of the most famous errors related to SQL Server is about connecting to SQL Server itself. Here is how it goes, most of the time developers have worked with SQL Server and knows pretty much every error which they face during development language. However, hardly they install fresh SQL Server. As the installation of the SQL Server is a rare occasion unless you are a DBA who is responsible for such an instance – the error faced during installations are pretty rare as well. http://www.youtube.com/watch?v=1k00z82u4OI Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• IntelliSense for Razor Hosting in non-Web Applications

  - by Rick Strahl

  When I posted my Razor Hosting article a couple of weeks ago I got a number of questions on how to get IntelliSense to work inside of Visual Studio while editing your templates. The answer to this question is mainly dependent on how Visual Studio recognizes assemblies, so a little background is required. If you open a template just on its own as a standalone file by clicking on it say in Explorer, Visual Studio will open up with the template in the editor, but you won’t get any IntelliSense on any of your related assemblies that you might be using by default. It’ll give Intellisense on base System namespace, but not on your imported assembly types. This makes sense: Visual Studio has no idea what the assembly associations for the single file are. There are two options available to you to make IntelliSense work for templates: Add the templates as included files to your non-Web project Add a BIN folder to your template’s folder and add all assemblies required there Including Templates in your Host Project By including templates into your Razor hosting project, Visual Studio will pick up the project’s assembly references and make IntelliSense available for any of the custom types in your project and on your templates. To see this work I moved the \Templates folder from the samples from the Debug\Bin folder into the project root and included the templates in the WinForm sample project. Here’s what this looks like in Visual Studio after the templates have been included:   Notice that I take my original example and type cast the Context object to the specific type that it actually represents – namely CustomContext – by using a simple code block: @{ CustomContext Model = Context as CustomContext; } After that assignment my Model local variable is in scope and IntelliSense works as expected. Note that you also will need to add any namespaces with the using command in this case: @using RazorHostingWinForm which has to be defined at the very top of a Razor document. BTW, while you can only pass in a single Context 'parameter’ to the template with the default template I’ve provided realize that you can also assign a complex object to Context. For example you could have a container object that references a variety of other objects which you can then cast to the appropriate types as needed: @{ ContextContainer container = Context as ContextContainer; CustomContext Model = container.Model; CustomDAO DAO = container.DAO; } and so forth. IntelliSense for your Custom Template Notice also that you can get IntelliSense for the top level template by specifying an inherits tag at the top of the document: @inherits RazorHosting.RazorTemplateFolderHost By specifying the above you can then get IntelliSense on your base template’s properties. For example, in my base template there are Request and Response objects. This is very useful especially if you end up creating custom templates that include your custom business objects as you can get effectively see full IntelliSense from the ‘page’ level down. For Html Help Builder for example, I’d have a Help object on the page and assuming I have the references available I can see all the way into that Help object without even having to do anything fancy. Note that the @inherits key is a GREAT and easy way to override the base template you normally specify as the default template. It allows you to create a custom template and as long as it inherits from the base template it’ll work properly. Since the last post I’ve also made some changes in the base template that allow hooking up some simple initialization logic so it gets much more easy to create custom templates and hook up custom objects with an IntializeTemplate() hook function that gets called with the Context and a Configuration object. These objects are objects you can pass in at runtime from your host application and then assign to custom properties on your template. For example the default implementation for RazorTemplateFolderHost does this: public override void InitializeTemplate(object context, object configurationData) { // Pick up configuration data and stuff into Request object RazorFolderHostTemplateConfiguration config = configurationData as RazorFolderHostTemplateConfiguration; this.Request.TemplatePath = config.TemplatePath; this.Request.TemplateRelativePath = config.TemplateRelativePath; // Just use the entire ConfigData as the model, but in theory // configData could contain many objects or values to set on // template properties this.Model = config.ConfigData as TModel; } to set up a strongly typed Model and the Request object. You can do much more complex hookups here of course and create complex base template pages that contain all the objects that you need in your code with strong typing. Adding a Bin folder to your Template’s Root Path Including templates in your host project works if you own the project and you’re the only one modifying the templates. However, if you are distributing the Razor engine as a templating/scripting solution as part of your application or development tool the original project is likely not available and so that approach is not practical. Another option you have is to add a Bin folder and add all the related assemblies into it. You can also add a Web.Config file with assembly references for any GAC’d assembly references that need to be associated with the templates. Between the web.config and bin folder Visual Studio can figure out how to provide IntelliSense. The Bin folder should contain: The RazorHosting.dll Your host project’s EXE or DLL – renamed to .dll if it’s an .exe Any external (bin folder) dependent assemblies Note that you most likely also want a reference to the host project if it contains references that are going to be used in templates. Visual Studio doesn’t recognize an EXE reference so you have to rename the EXE to DLL to make it work. Apparently the binary signature of EXE and DLL files are identical and it just works – learn something new everyday… For GAC assembly references you can add a web.config file to your template root. The Web.config file then should contain any full assembly references to GAC components: <configuration> <system.web> <compilation debug="true"> <assemblies> <add assembly="System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" /> <add assembly="System.Web, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" /> <add assembly="System.Web.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" /> </assemblies> </compilation> </system.web> </configuration> And with that you should get full IntelliSense. Note that if you add a BIN folder and you also have the templates in your Visual Studio project Visual Studio will complain about reference conflicts as it’s effectively seeing both the project references and the ones in the bin folder. So it’s probably a good idea to use one or the other but not both at the same time :-) Seeing IntelliSense in your Razor templates is a big help for users of your templates. If you’re shipping an application level scripting solution especially it’ll be real useful for your template consumers/users to be able to get some quick help on creating customized templates – after all that’s what templates are all about – easy customization. Making sure that everything is referenced in your bin folder and web.config is a good idea and it’s great to see that Visual Studio (and presumably WebMatrix/Visual Web Developer as well) will be able to pick up your custom IntelliSense in Razor templates.© Rick Strahl, West Wind Technologies, 2005-2011Posted in Razor  

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• MySQL Cluster 7.3 Labs Release – Foreign Keys Are In!

  - by Mat Keep

  0 0 1 1097 6254 Homework 52 14 7337 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} Summary (aka TL/DR): Support for Foreign Key constraints has been one of the most requested feature enhancements for MySQL Cluster. We are therefore extremely excited to announce that Foreign Keys are part of the first Labs Release of MySQL Cluster 7.3 – available for download, evaluation and feedback now! (Select the mysql-cluster-7.3-labs-June-2012 build) In this blog, I will attempt to discuss the design rationale, implementation, configuration and steps to get started in evaluating the first MySQL Cluster 7.3 Labs Release. Pace of Innovation It was only a couple of months ago that we announced the General Availability (GA) of MySQL Cluster 7.2, delivering 1 billion Queries per Minute, with 70x higher cross-shard JOIN performance, Memcached NoSQL key-value API and cross-data center replication.  This release has been a huge hit, with downloads and deployments quickly reaching record levels. The announcement of the first MySQL Cluster 7.3 Early Access lab release at today's MySQL Innovation Day event demonstrates the continued pace in Cluster development, and provides an opportunity for the community to evaluate and feedback on new features they want to see. What’s the Plan for MySQL Cluster 7.3? Well, Foreign Keys, as you may have gathered by now (!), and this is the focus of this first Labs Release. As with MySQL Cluster 7.2, we plan to publish a series of preview releases for 7.3 that will incrementally add new candidate features for a final GA release (subject to usual safe harbor statement below*), including: - New NoSQL APIs; - Features to automate the configuration and provisioning of multi-node clusters, on premise or in the cloud; - Performance and scalability enhancements; - Taking advantage of features in the latest MySQL 5.x Server GA. Design Rationale MySQL Cluster is designed as a “Not-Only-SQL” database. It combines attributes that enable users to blend the best of both relational and NoSQL technologies into solutions that deliver web scalability with 99.999% availability and real-time performance, including: Concurrent NoSQL and SQL access to the database; Auto-sharding with simple scale-out across commodity hardware; Multi-master replication with failover and recovery both within and across data centers; Shared-nothing architecture with no single point of failure; Online scaling and schema changes; ACID compliance and support for complex queries, across shards. Native support for Foreign Key constraints enables users to extend the benefits of MySQL Cluster into a broader range of use-cases, including: - Packaged applications in areas such as eCommerce and Web Content Management that prescribe databases with Foreign Key support. - In-house developments benefiting from Foreign Key constraints to simplify data models and eliminate the additional application logic needed to maintain data consistency and integrity between tables. Implementation The Foreign Key functionality is implemented directly within MySQL Cluster’s data nodes, allowing any client API accessing the cluster to benefit from them – whether using SQL or one of the NoSQL interfaces (Memcached, C++, Java, JPA or HTTP/REST.) The core referential actions defined in the SQL:2003 standard are implemented: CASCADE RESTRICT NO ACTION SET NULL In addition, the MySQL Cluster implementation supports the online adding and dropping of Foreign Keys, ensuring the Cluster continues to serve both read and write requests during the operation. An important difference to note with the Foreign Key implementation in InnoDB is that MySQL Cluster does not support the updating of Primary Keys from within the Data Nodes themselves - instead the UPDATE is emulated with a DELETE followed by an INSERT operation. Therefore an UPDATE operation will return an error if the parent reference is using a Primary Key, unless using CASCADE action, in which case the delete operation will result in the corresponding rows in the child table being deleted. The Engineering team plans to change this behavior in a subsequent preview release. Also note that when using InnoDB "NO ACTION" is identical to "RESTRICT". In the case of MySQL Cluster “NO ACTION” means “deferred check”, i.e. the constraint is checked before commit, allowing user-defined triggers to automatically make changes in order to satisfy the Foreign Key constraints. Configuration There is nothing special you have to do here – Foreign Key constraint checking is enabled by default. If you intend to migrate existing tables from another database or storage engine, for example from InnoDB, there are a couple of best practices to observe: 1. Analyze the structure of the Foreign Key graph and run the ALTER TABLE ENGINE=NDB in the correct sequence to ensure constraints are enforced 2. Alternatively drop the Foreign Key constraints prior to the import process and then recreate when complete. Getting Started Read this blog for a demonstration of using Foreign Keys with MySQL Cluster.  You can download MySQL Cluster 7.3 Labs Release with Foreign Keys today - (select the mysql-cluster-7.3-labs-June-2012 build) If you are new to MySQL Cluster, the Getting Started guide will walk you through installing an evaluation cluster on a singe host (these guides reflect MySQL Cluster 7.2, but apply equally well to 7.3) Post any questions to the MySQL Cluster forum where our Engineering team will attempt to assist you. Post any bugs you find to the MySQL bug tracking system (select MySQL Cluster from the Category drop-down menu) And if you have any feedback, please post them to the Comments section of this blog. Summary MySQL Cluster 7.2 is the GA, production-ready release of MySQL Cluster. This first Labs Release of MySQL Cluster 7.3 gives you the opportunity to preview and evaluate future developments in the MySQL Cluster database, and we are very excited to be able to share that with you. Let us know how you get along with MySQL Cluster 7.3, and other features that you want to see in future releases. * Safe Harbor Statement This information is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, and timing of any features or functionality described for Oracle’s products remains at the sole discretion of Oracle.

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• CodePlex Daily Summary for Sunday, June 01, 2014

  CodePlex Daily Summary for Sunday, June 01, 2014Popular ReleasesSandcastle Help File Builder: Help File Builder and Tools v2014.5.31.0: General InformationIMPORTANT: On some systems, the content of the ZIP file is blocked and the installer may fail to run. Before extracting it, right click on the ZIP file, select Properties, and click on the Unblock button if it is present in the lower right corner of the General tab in the properties dialog. This release completes removal of the branding transformations and implements the new VS2013 presentation style that utilizes the new lightweight website format. Several breaking cha...Tooltip Web Preview: ToolTip Web Preview: Version 1.0Database Helper: Release 1.0.0.0: First Release of Database HelperCoMaSy: CoMaSy1.0.2: !Contact Management SystemImage View Slider: Image View Slider: This is a .NET component. We create this using VB.NET. Here you can use an Image Viewer with several properties to your application form. We wish somebody to improve freely. Try this out! Author : Steven Renaldo Antony Yustinus Arjuna Purnama Putra Andre Wijaya P Martin Lidau PBK GENAP 2014 - TI UKDWAspose for Apache POI: Missing Features of Apache POI WP - v 1.1: Release contain the Missing Features in Apache POI WP SDK in Comparison with Aspose.Words for dealing with Microsoft Word. What's New ?Following Examples: Insert Picture in Word Document Insert Comments Set Page Borders Mail Merge from XML Data Source Moving the Cursor Feedback and Suggestions Many more examples are yet to come here. Keep visiting us. Raise your queries and suggest more examples via Aspose Forums or via this social coding site.babelua: V1.5.6.0: V1.5.6.0 - 2014.5.30New feature: support quick-cocos2d-x project now; support text search in scripts folder now, you can use this function in Search Result Window;SEToolbox: 01.032.014 Release 1: Added fix when loading game Textures for icons causing 'Unable to read beyond the end of the stream'. Added new Resource Report, that displays all in game resources in a concise report. Added in temp directory cleaner, to keep excess files from building up. Fixed use of colors on the windows, to work better with desktop schemes. Adding base support for multilingual resources. This will allow loading of the Space Engineers resources to show localized names, and display localized date a...ClosedXML - The easy way to OpenXML: ClosedXML 0.71.2: More memory and performance improvements. Fixed an issue with pivot table field order.Fancontroller: Fancontroller: Initial releaseVi-AIO SearchBar: Vi – AIO Search Bar: Version 1.0Top Verses ( Ayat Emas ): Binary Top Verses: This one is the bin folder of the component. the .dll component is inside.Traditional Calendar Component: Traditional Calender Converter: Duta Wacana Christian University This file containing Traditional Calendar Component and Demo Aplication that using Traditional Calendar Component. This component made with .NET Framework 4 and the programming language is C# .SQLSetupHelper: 1.0.0.0: First Stable Version of SQL SetupComposite Iconote: Composite Iconote: This is a composite has been made by Microsoft Visual Studio 2013. Requirement: To develop this composite or use this component in your application, your computer must have .NET framework 4.5 or newer.Magick.NET: Magick.NET 6.8.9.101: Magick.NET linked with ImageMagick 6.8.9.1. Breaking changes: - Int/short Set methods of WritablePixelCollection are now unsigned. - The Q16 build no longer uses HDRI, switch to the new Q16-HDRI build if you need HDRI.fnr.exe - Find And Replace Tool: 1.7: Bug fixes Refactored logic for encoding text values to command line to handle common edge cases where find/replace operation works in GUI but not in command line Fix for bug where selection in Encoding drop down was different when generating command line in some cases. It was reported in: https://findandreplace.codeplex.com/workitem/34 Fix for "Backslash inserted before dot in replacement text" reported here: https://findandreplace.codeplex.com/discussions/541024 Fix for finding replacing...VG-Ripper & PG-Ripper: VG-Ripper 2.9.59: changes NEW: Added Support for 'GokoImage.com' links NEW: Added Support for 'ViperII.com' links NEW: Added Support for 'PixxxView.com' links NEW: Added Support for 'ImgRex.com' links NEW: Added Support for 'PixLiv.com' links NEW: Added Support for 'imgsee.me' links NEW: Added Support for 'ImgS.it' linksToolbox for Dynamics CRM 2011/2013: XrmToolBox (v1.2014.5.28): XrmToolbox improvement XrmToolBox updates (v1.2014.5.28)Fix connecting to a connection with custom authentication without saved password Tools improvement New tool!Solution Components Mover (v1.2014.5.22) Transfer solution components from one solution to another one Import/Export NN relationships (v1.2014.3.7) Allows you to import and export many to many relationships Tools updatesAttribute Bulk Updater (v1.2014.5.28) Audit Center (v1.2014.5.28) View Layout Replicator (v1.2014.5.28) Scrip...Microsoft Ajax Minifier: Microsoft Ajax Minifier 5.10: Fix for Issue #20875 - echo switch doesn't work for CSS CSS should honor the SASS source-file comments JS should allow multi-line comment directivesNew ProjectsCet MicroWPF: WPF-like library for simple graphic-UI application using Netduino (Plus) 2 and the FTDI FT800 Eve board.Fakemons: Some Fakmons, powered by XML, XSLT, CSS and JavascriptFling OS: Fling OS is a C# operating system project aiming to create a new, managed operating system from the ground up.MudRoom: Experimental tool sets in mud parsing and area definitionOOP-2112110158: My name's NgocDungRoslynResearch: Roslyn ResearchTHD - Control de Usuarios: control de usuarios y permisosWPF Kinect User Controls: WPF Kinect User Control project provide simple Tilt and Skeleton Tracking Parameter Controls.

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• Adding proper THEAD sections to a GridView

  - by Rick Strahl

  I’m working on some legacy code for a customer today and dealing with a page that has my favorite ‘friend’ on it: A GridView control. The ASP.NET GridView control (and also the older DataGrid control) creates some pretty messed up HTML. One of the more annoying things it does is to generate all rows including the header into the page in the <tbody> section of the document rather than in a properly separated <thead> section. Here’s is typical GridView generated HTML output: <table class="tablesorter blackborder" cellspacing="0" rules="all" border="1" id="Table1" style="border-collapse:collapse;"> <tr> <th scope="col">Name</th> <th scope="col">Company</th> <th scope="col">Entered</th><th scope="col">Balance</th> </tr> <tr> <td>Frank Hobson</td><td>Hobson Inc.</td> <td>10/20/2010 12:00:00 AM</td><td>240.00</td> </tr> ... </table> Notice that all content – both the headers and the body of the table – are generated directly under the <table> tag and there’s no explicit use of <tbody> or <thead> (or <tfooter> for that matter). When the browser renders this the document some default settings kick in and the DOM tree turns into something like this: <table> <tbody> <tr> <-- header <tr> <—detail row <tr> <—detail row </tbody> </table> Now if you’re just rendering the Grid server side and you’re applying all your styles through CssClass assignments this isn’t much of a problem. However, if you want to style your grid more generically using hierarchical CSS selectors it gets a lot more tricky to format tables that don’t properly delineate headers and body content. Also many plug-ins and other JavaScript utilities that work on tables require a properly formed table layout, and many of these simple won’t work out of the box with a GridView. For example, one of the things I wanted to do for this app is use the jQuery TableSorter plug-in which – not surprisingly – requires to work of table headers in the DOM document. Out of the box, the TableSorter plug-in doesn’t work with GridView controls, because the lack of a <thead> section to work on. Luckily with a little help of some jQuery scripting there’s a real easy fix to this problem. Basically, if we know the GridView generated table has a header in it, code like the following will move the headers from <tbody> to <thead>: <script type="text/javascript"> $(document).ready(function () { // Fix up GridView to support THEAD tags $("#gvCustomers tbody").before("<thead><tr></tr></thead>"); $("#gvCustomers thead tr").append($("#gvCustomers th")); $("#gvCustomers tbody tr:first").remove(); $("#gvCustomers").tablesorter({ sortList: [[1, 0]] }); }); </script> And voila you have a table that now works with the TableSorter plug-in. If you use GridView’s a lot you might want something a little more generic so the following does the same thing but should work more generically on any GridView/DataGrid missing its <thead> tag: function fixGridView(tableEl) {            var jTbl = $(tableEl);         if(jTbl.find("tbody>tr>th").length > 0) {         jTbl.find("tbody").before("<thead><tr></tr></thead>");         jTbl.find("thead tr").append(jTbl.find("th"));         jTbl.find("tbody tr:first").remove();     } } which you can call like this: $(document).ready(function () { fixGridView( $("#gvCustomers") ); $("#gvCustomers").tablesorter({ sortList: [[1, 0]] }); }); Server Side THEAD Rendering [updated from comments 11/21/2010] Several commenters pointed out that you can also do this on the server side by using the GridView.HeaderRow.TableSection property to force rendering with a proper table header. I was unaware of this option actually – not exactly an easy one to discover. One issue here is that timing of this needs to happen during the databinding process so you need to use an event handler: this.gvCustomers.DataBound += (object o, EventArgs ev) => { gvCustomers.HeaderRow.TableSection = TableRowSection.TableHeader; }; this.gvCustomers.DataSource = custList; this.gvCustomers.DataBind(); You can apply the same logic for the FooterRow. It’s beyond me why this rendering mode isn’t the default for a GridView – why would you ever want to have a table that doesn’t use a THEAD section??? But I disgress :-) I don’t use GridViews much anymore – opting for more flexible approaches using ListViews or even plain code based views or other custom displays that allow more control over layout, but I still see a lot of old code that does use them old clunkers including my own :) (gulp) and this does make life a little bit easier especially if you’re working with any of the jQuery table related plug-ins that expect a proper table structure.© Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  jQuery  

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• SQL SERVER – Weekly Series – Memory Lane – #032

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Complete Series of Database Coding Standards and Guidelines SQL SERVER Database Coding Standards and Guidelines – Introduction SQL SERVER – Database Coding Standards and Guidelines – Part 1 SQL SERVER – Database Coding Standards and Guidelines – Part 2 SQL SERVER Database Coding Standards and Guidelines Complete List Download Explanation and Example – SELF JOIN When all of the data you require is contained within a single table, but data needed to extract is related to each other in the table itself. Examples of this type of data relate to Employee information, where the table may have both an Employee’s ID number for each record and also a field that displays the ID number of an Employee’s supervisor or manager. To retrieve the data tables are required to relate/join to itself. Insert Multiple Records Using One Insert Statement – Use of UNION ALL This is very interesting question I have received from new developer. How can I insert multiple values in table using only one insert? Now this is interesting question. When there are multiple records are to be inserted in the table following is the common way using T-SQL. Function to Display Current Week Date and Day – Weekly Calendar Straight blog post with script to find current week date and day based on the parameters passed in the function.  2008 In my beginning years, I have almost same confusion as many of the developer had in their earlier years. Here are two of the interesting question which I have attempted to answer in my early year. Even if you are experienced developer may be you will still like to read following two questions: Order Of Column In Index Order of Conditions in WHERE Clauses Example of DISTINCT in Aggregate Functions Have you ever used DISTINCT with the Aggregation Function? Here is a simple example about how users can do it. Create a Comma Delimited List Using SELECT Clause From Table Column Straight to script example where I explained how to do something easy and quickly. Compound Assignment Operators SQL SERVER 2008 has introduced new concept of Compound Assignment Operators. Compound Assignment Operators are available in many other programming languages for quite some time. Compound Assignment Operators is operator where variables are operated upon and assigned on the same line. PIVOT and UNPIVOT Table Examples Here is a very interesting question – the answer to the question can be YES or NO both. “If we PIVOT any table and UNPIVOT that table do we get our original table?” Read the blog post to get the explanation of the question above. 2009 What is Interim Table – Simple Definition of Interim Table The interim table is a table that is generated by joining two tables and not the final result table. In other words, when two tables are joined they create an interim table as resultset but the resultset is not final yet. It may be possible that more tables are about to join on the interim table, and more operations are still to be applied on that table (e.g. Order By, Having etc). Besides, it may be possible that there is no interim table; sometimes final table is what is generated when the query is run. 2010 Stored Procedure and Transactions If Stored Procedure is transactional then, it should roll back complete transactions when it encounters any errors. Well, that does not happen in this case, which proves that Stored Procedure does not only provide just the transactional feature to a batch of T-SQL. Generate Database Script for SQL Azure When talking about SQL Azure the most common complaint I hear is that the script generated from stand-along SQL Server database is not compatible with SQL Azure. This was true for some time for sure but not any more. If you have SQL Server 2008 R2 installed you can follow the guideline below to generate a script which is compatible with SQL Azure. Convert IN to EXISTS – Performance Talk It is NOT necessary that every time when IN is replaced by EXISTS it gives better performance. However, in our case listed above it does for sure give better performance. You can read about this subject in the associated blog post. Subquery or Join – Various Options – SQL Server Engine Knows the Best Every single time whenever there is a performance tuning exercise, I hear the conversation from developer where some prefer subquery and some prefer join. In this two part blog post, I explain the same in the detail with examples. Part 1 | Part 2 Merge Operations – Insert, Update, Delete in Single Execution MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. 2011 Puzzle – Statistics are not updated but are Created Once Here is the quick scenario about my setup. Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated – WHY? Question to You – When to use Function and When to use Stored Procedure Personally, I believe that they are both different things - they cannot be compared. I can say, it will be like comparing apples and oranges. Each has its own unique use. However, they can be used interchangeably at many times and in real life (i.e., production environment). I have personally seen both of these being used interchangeably many times. This is the precise reason for asking this question. 2012 In year 2012 I had two interesting series ran on the blog. If there is no fun in learning, the learning becomes a burden. For the same reason, I had decided to build a three part quiz around SEQUENCE. The quiz was to identify the next value of the sequence. I encourage all of you to take part in this fun quiz. Guess the Next Value – Puzzle 1 Guess the Next Value – Puzzle 2 Guess the Next Value – Puzzle 3 Guess the Next Value – Puzzle 4 Simple Example to Configure Resource Governor – Introduction to Resource Governor Resource Governor is a feature which can manage SQL Server Workload and System Resource Consumption. We can limit the amount of CPU and memory consumption by limiting /governing /throttling on the SQL Server. If there are different workloads running on SQL Server and each of the workload needs different resources or when workloads are competing for resources with each other and affecting the performance of the whole server resource governor is a very important task. Tricks to Replace SELECT * with Column Names – SQL in Sixty Seconds #017 – Video  Retrieves unnecessary columns and increases network traffic When a new columns are added views needs to be refreshed manually Leads to usage of sub-optimal execution plan Uses clustered index in most of the cases instead of using optimal index It is difficult to debug SQL SERVER – Load Generator – Free Tool From CodePlex The best part of this SQL Server Load Generator is that users can run multiple simultaneous queries again SQL Server using different login account and different application name. The interface of the tool is extremely easy to use and very intuitive as well. A Puzzle – Swap Value of Column Without Case Statement Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Movement prediction for non-shooters

  - by ShadowChaser

  I'm working on an isometric 2D game with moderate-scale multiplayer, approximately 20-30 players connected at once to a persistent server. I've had some difficulty getting a good movement prediction implementation in place. Physics/Movement The game doesn't have a true physics implementation, but uses the basic principles to implement movement. Rather than continually polling input, state changes (ie/ mouse down/up/move events) are used to change the state of the character entity the player is controlling. The player's direction (ie/ north-east) is combined with a constant speed and turned into a true 3D vector - the entity's velocity. In the main game loop, "Update" is called before "Draw". The update logic triggers a "physics update task" that tracks all entities with a non-zero velocity uses very basic integration to change the entities position. For example: entity.Position += entity.Velocity.Scale(ElapsedTime.Seconds) (where "Seconds" is a floating point value, but the same approach would work for millisecond integer values). The key point is that no interpolation is used for movement - the rudimentary physics engine has no concept of a "previous state" or "current state", only a position and velocity. State Change and Update Packets When the velocity of the character entity the player is controlling changes, a "move avatar" packet is sent to the server containing the entity's action type (stand, walk, run), direction (north-east), and current position. This is different from how 3D first person games work. In a 3D game the velocity (direction) can change frame to frame as the player moves around. Sending every state change would effectively transmit a packet per frame, which would be too expensive. Instead, 3D games seem to ignore state changes and send "state update" packets on a fixed interval - say, every 80-150ms. Since speed and direction updates occur much less frequently in my game, I can get away with sending every state change. Although all of the physics simulations occur at the same speed and are deterministic, latency is still an issue. For that reason, I send out routine position update packets (similar to a 3D game) but much less frequently - right now every 250ms, but I suspect with good prediction I can easily boost it towards 500ms. The biggest problem is that I've now deviated from the norm - all other documentation, guides, and samples online send routine updates and interpolate between the two states. It seems incompatible with my architecture, and I need to come up with a better movement prediction algorithm that is closer to a (very basic) "networked physics" architecture. The server then receives the packet and determines the players speed from it's movement type based on a script (Is the player able to run? Get the player's running speed). Once it has the speed, it combines it with the direction to get a vector - the entity's velocity. Some cheat detection and basic validation occurs, and the entity on the server side is updated with the current velocity, direction, and position. Basic throttling is also performed to prevent players from flooding the server with movement requests. After updating its own entity, the server broadcasts an "avatar position update" packet to all other players within range. The position update packet is used to update the client side physics simulations (world state) of the remote clients and perform prediction and lag compensation. Prediction and Lag Compensation As mentioned above, clients are authoritative for their own position. Except in cases of cheating or anomalies, the client's avatar will never be repositioned by the server. No extrapolation ("move now and correct later") is required for the client's avatar - what the player sees is correct. However, some sort of extrapolation or interpolation is required for all remote entities that are moving. Some sort of prediction and/or lag-compensation is clearly required within the client's local simulation / physics engine. Problems I've been struggling with various algorithms, and have a number of questions and problems: Should I be extrapolating, interpolating, or both? My "gut feeling" is that I should be using pure extrapolation based on velocity. State change is received by the client, client computes a "predicted" velocity that compensates for lag, and the regular physics system does the rest. However, it feels at odds to all other sample code and articles - they all seem to store a number of states and perform interpolation without a physics engine. When a packet arrives, I've tried interpolating the packet's position with the packet's velocity over a fixed time period (say, 200ms). I then take the difference between the interpolated position and the current "error" position to compute a new vector and place that on the entity instead of the velocity that was sent. However, the assumption is that another packet will arrive in that time interval, and it's incredibly difficult to "guess" when the next packet will arrive - especially since they don't all arrive on fixed intervals (ie/ state changes as well). Is the concept fundamentally flawed, or is it correct but needs some fixes / adjustments? What happens when a remote player stops? I can immediately stop the entity, but it will be positioned in the "wrong" spot until it moves again. If I estimate a vector or try to interpolate, I have an issue because I don't store the previous state - the physics engine has no way to say "you need to stop after you reach position X". It simply understands a velocity, nothing more complex. I'm reluctant to add the "packet movement state" information to the entities or physics engine, since it violates basic design principles and bleeds network code across the rest of the game engine. What should happen when entities collide? There are three scenarios - the controlling player collides locally, two entities collide on the server during a position update, or a remote entity update collides on the local client. In all cases I'm uncertain how to handle the collision - aside from cheating, both states are "correct" but at different time periods. In the case of a remote entity it doesn't make sense to draw it walking through a wall, so I perform collision detection on the local client and cause it to "stop". Based on point #2 above, I might compute a "corrected vector" that continually tries to move the entity "through the wall" which will never succeed - the remote avatar is stuck there until the error gets too high and it "snaps" into position. How do games work around this?

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• SQL SERVER – Weekly Series – Memory Lane – #034

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 UDF – User Defined Function to Strip HTML – Parse HTML – No Regular Expression The UDF used in the blog does fantastic task – it scans entire HTML text and removes all the HTML tags. It keeps only valid text data without HTML task. This is one of the quite commonly requested tasks many developers have to face everyday. De-fragmentation of Database at Operating System to Improve Performance Operating system skips MDF file while defragging the entire filesystem of the operating system. It is absolutely fine and there is no impact of the same on performance. Read the entire blog post for my conversation with our network engineers. Delay Function – WAITFOR clause – Delay Execution of Commands How do you delay execution of the commands in SQL Server – ofcourse by using WAITFOR keyword. In this blog post, I explain the same with the help of T-SQL script. Find Length of Text Field To measure the length of TEXT fields the function is DATALENGTH(textfield). Len will not work for text field. As of SQL Server 2005, developers should migrate all the text fields to VARCHAR(MAX) as that is the way forward. Retrieve Current Date Time in SQL Server CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} There are three ways to retrieve the current datetime in SQL SERVER. CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} Explanation and Comparison of NULLIF and ISNULL An interesting observation is NULLIF returns null if it comparison is successful, whereas ISNULL returns not null if its comparison is successful. In one way they are opposite to each other. Here is my question to you - How to create infinite loop using NULLIF and ISNULL? If this is even possible? 2008 Introduction to SERVERPROPERTY and example SERVERPROPERTY is a very interesting system function. It returns many of the system values. I use it very frequently to get different server values like Server Collation, Server Name etc. SQL Server Start Time We can use DMV to find out what is the start time of SQL Server in 2008 and later version. In this blog you can see how you can do the same. Find Current Identity of Table Many times we need to know what is the current identity of the column. I have found one of my developers using aggregated function MAX () to find the current identity. However, I prefer following DBCC command to figure out current identity. Create Check Constraint on Column Some time we just need to create a simple constraint over the table but I have noticed that developers do many different things to make table column follow rules than just creating constraint. I suggest constraint is a very useful concept and every SQL Developer should pay good attention to this subject. 2009 List Schema Name and Table Name for Database This is one of the blog post where I straight forward display script. One of the kind of blog posts, which I still love to read and write. Clustered Index on Separate Drive From Table Location A table devoid of primary key index is called heap, and here data is not arranged in a particular order, which gives rise to issues that adversely affect performance. Data must be stored in some kind of order. If we put clustered index on it then the order will be forced by that index and the data will be stored in that particular order. Understanding Table Hints with Examples Hints are options and strong suggestions specified for enforcement by the SQL Server query processor on DML statements. The hints override any execution plan the query optimizer might select for a query. 2010 Data Pages in Buffer Pool – Data Stored in Memory Cache One of my earlier year article, which I still read it many times and point developers to read it again. It is clear from the Resultset that when more than one index is used, datapages related to both or all of the indexes are stored in Memory Cache separately. TRANSACTION, DML and Schema Locks Can you create a situation where you can see Schema Lock? Well, this is a very simple question, however during the interview I notice over 50 candidates failed to come up with the scenario. In this blog post, I have demonstrated the situation where we can see the schema lock in database. 2011 Solution – Puzzle – Statistics are not updated but are Created Once In this example I have created following situation: Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated Auto Update Statistics and Auto Create Statistics for database is TRUE Now I have requested two things in the example 1) Why this is happening? 2) How to fix this issue? Selecting Domain from Email Address This is a straight to script blog post where I explain how to select only domain name from entire email address. Solution – Generating Zero Without using Any Numbers in T-SQL How to get zero digit without using any digit? This is indeed a very interesting question and the answer is even interesting. Try to come up with answer in next 10 minutes and if you can’t come up with the answer the blog post read this post for solution. 2012 Simple Explanation and Puzzle with SOUNDEX Function and DIFFERENCE Function In simple words - SOUNDEX converts an alphanumeric string to a four-character code to find similar-sounding words or names. DIFFERENCE function returns an integer value. The  integer returned is the number of characters in the SOUNDEX values that are the same. Read Only Files and SQL Server Management Studio (SSMS) I have come across a very interesting feature in SSMS related to “Read Only” files. I believe it is a little unknown feature as well so decided to write a blog about the same. Identifying Column Data Type of uniqueidentifier without Querying System Tables How do I know if any table has a uniqueidentifier column and what is its value without using any DMV or System Catalogues? Only information you know is the table name and you are allowed to return any kind of error if the table does not have uniqueidentifier column. Read the blog post to find the answer. Solution – User Not Able to See Any User Created Object in Tables – Security and Permissions Issue Interesting question – “When I try to connect to SQL Server, it lets me connect just fine as well let me open and explore the database. I noticed that I do not see any user created instances but when my colleague attempts to connect to the server, he is able to explore the database as well see all the user created tables and other objects. Can you help me fix it?” Importing CSV File Into Database – SQL in Sixty Seconds #018 – Video Here is interesting small 60 second video on how to import CSV file into Database. ColumnStore Index – Batch Mode vs Row Mode Here is the logic behind when Columnstore Index uses Batch Mode and when it uses Row Mode. A batch typically represents about 1000 rows of data. Batch mode processing also uses algorithms that are optimized for the multicore CPUs and increased memory throughput. Follow up – Usage of $rowguid and $IDENTITY This is an excellent follow up blog post of my earlier blog post where I explain where to use $rowguid and $identity.  If you do not know the difference between them, this is a blog with a script example. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Using Open MQ as an Oracle CEP Event Source

  - by seth.white

  I helped an Oracle CEP customer recently who wanted to use Open MQ has an event source for their Oracle CEP application.  In this case, the Oracle CEP application was being used to provide monitoring for an electronic commerce website, however, the steps for configuring Open MQ are entirely independent of the application logic. I thought I would list the configuration steps in a blog post in case they might help others in the future. Note that although the Oracle CEP documentation states that only WebLogic and Tibco JMS are "officially" supported, any JMS implementation that provides a Java client should work with Oracle CEP. The first step is to add an adapter to the application's EPN. This can be done in the usual way, using the Eclipse IDE. The end result is something like the following bit of configuration in the application's Spring application context. Note that the provider attribute value of 'jms-inbound' specifies that the out-of-the-box JMS adapter is being used. <wlevs:adapter id="helloworldAdapter" provider="jms-inbound"> </wlevs:adapter>   Next, configure the inbound adapter so that it can connect to Open MQ in the Oracle CEP configuration file (config.xml). The snippet below provides an example of what this configuration should look like. The exact values specified for jndi-provider-url, jndi-factory, connection-jndi-name, destination-jndi-name elements will depend on your Open MQ configuration.  For example , if the name of your Open MQ topic destination is 'ElectronicCommerceTopic', then you would specify that as the destination-jndi-name.  The name of your Open MQ connection factory goes in the connection-jndi-name element. In my simple example, I also specify in event-type element so that the out-of-the-box JMS adapter will attempt to automatically convert incoming messages to events of type HelloWorldEvent. In a more complex application, one would configure a custom converter on the JMS adapter to convert from messages to events.  The Oracle CEP 11.1.3 documentation describes how to do this.   <jms-adapter> <name>helloworldAdapter</name> <event-type>HelloWorldEvent</event-type> <jndi-provider-url>file:///C:/Temp</jndi-provider-url> <jndi-factory>com.sun.jndi.fscontext.RefFSContextFactory</jndi-factory> <connection-jndi-name>YourJMSConnectionFactoryName</connection-jndi-name> <destination-jndi-name>YourJMSDestinationName</destination-jndi-name> </jms-adapter>   Finally, one needs to package the client-side Open MQ jars so that the classes that they contain are available to the Oracle CEP runtime. The recommended way for doing this in the Oracle CEP 11.1.3 release is to package the classes as a library module or simply place them in the application bundle.  The advantage of deploying the classes as a library module is that they are available to any application that wants to connect to Open MQ. In my case, I packaged the classes in my application bundle. A best practice when you want to include additional jars in your application bundle is to create a 'lib' directory in your Eclipse project and then copy the required jars into that directory.  Then, use the support that Eclipse provides to add the jars to the bundle classpath (which makes the classes part of your application in the same way that regular application classes are), and export all of the classes from your application bundle so that they are available to the Oracle CEP server runtime.  The screenshot below Illustrates how this is done in Eclipse.  The bundle classpath contains two Open MQ jars and all packages in the jars are exported.     Finally, import the javax.jms and javax.naming packages into the application module as these are needed by the Open MQ classes. The screenshot below shows the complete list of package imports for my sample application.       Once you have completed these steps, you should be able to build and deploy your application and begin receiving inbound messages from Open MQ. 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• Fraud Detection with the SQL Server Suite Part 2

  - by Dejan Sarka

  This is the second part of the fraud detection whitepaper. You can find the first part in my previous blog post about this topic. My Approach to Data Mining Projects It is impossible to evaluate the time and money needed for a complete fraud detection infrastructure in advance. Personally, I do not know the customer’s data in advance. I don’t know whether there is already an existing infrastructure, like a data warehouse, in place, or whether we would need to build one from scratch. Therefore, I always suggest to start with a proof-of-concept (POC) project. A POC takes something between 5 and 10 working days, and involves personnel from the customer’s site – either employees or outsourced consultants. The team should include a subject matter expert (SME) and at least one information technology (IT) expert. The SME must be familiar with both the domain in question as well as the meaning of data at hand, while the IT expert should be familiar with the structure of data, how to access it, and have some programming (preferably Transact-SQL) knowledge. With more than one IT expert the most time consuming work, namely data preparation and overview, can be completed sooner. I assume that the relevant data is already extracted and available at the very beginning of the POC project. If a customer wants to have their people involved in the project directly and requests the transfer of knowledge, the project begins with training. I strongly advise this approach as it offers the establishment of a common background for all people involved, the understanding of how the algorithms work and the understanding of how the results should be interpreted, a way of becoming familiar with the SQL Server suite, and more. Once the data has been extracted, the customer’s SME (i.e. the analyst), and the IT expert assigned to the project will learn how to prepare the data in an efficient manner. Together with me, knowledge and expertise allow us to focus immediately on the most interesting attributes and identify any additional, calculated, ones soon after. By employing our programming knowledge, we can, for example, prepare tens of derived variables, detect outliers, identify the relationships between pairs of input variables, and more, in only two or three days, depending on the quantity and the quality of input data. I favor the customer’s decision of assigning additional personnel to the project. For example, I actually prefer to work with two teams simultaneously. I demonstrate and explain the subject matter by applying techniques directly on the data managed by each team, and then both teams continue to work on the data overview and data preparation under our supervision. I explain to the teams what kind of results we expect, the reasons why they are needed, and how to achieve them. Afterwards we review and explain the results, and continue with new instructions, until we resolve all known problems. Simultaneously with the data preparation the data overview is performed. The logic behind this task is the same – again I show to the teams involved the expected results, how to achieve them and what they mean. This is also done in multiple cycles as is the case with data preparation, because, quite frankly, both tasks are completely interleaved. A specific objective of the data overview is of principal importance – it is represented by a simple star schema and a simple OLAP cube that will first of all simplify data discovery and interpretation of the results, and will also prove useful in the following tasks. The presence of the customer’s SME is the key to resolving possible issues with the actual meaning of the data. We can always replace the IT part of the team with another database developer; however, we cannot conduct this kind of a project without the customer’s SME. After the data preparation and when the data overview is available, we begin the scientific part of the project. I assist the team in developing a variety of models, and in interpreting the results. The results are presented graphically, in an intuitive way. While it is possible to interpret the results on the fly, a much more appropriate alternative is possible if the initial training was also performed, because it allows the customer’s personnel to interpret the results by themselves, with only some guidance from me. The models are evaluated immediately by using several different techniques. One of the techniques includes evaluation over time, where we use an OLAP cube. After evaluating the models, we select the most appropriate model to be deployed for a production test; this allows the team to understand the deployment process. There are many possibilities of deploying data mining models into production; at the POC stage, we select the one that can be completed quickly. Typically, this means that we add the mining model as an additional dimension to an existing DW or OLAP cube, or to the OLAP cube developed during the data overview phase. Finally, we spend some time presenting the results of the POC project to the stakeholders and managers. Even from a POC, the customer will receive lots of benefits, all at the sole risk of spending money and time for a single 5 to 10 day project: The customer learns the basic patterns of frauds and fraud detection The customer learns how to do the entire cycle with their own people, only relying on me for the most complex problems The customer’s analysts learn how to perform much more in-depth analyses than they ever thought possible The customer’s IT experts learn how to perform data extraction and preparation much more efficiently than they did before All of the attendees of this training learn how to use their own creativity to implement further improvements of the process and procedures, even after the solution has been deployed to production The POC output for a smaller company or for a subsidiary of a larger company can actually be considered a finished, production-ready solution It is possible to utilize the results of the POC project at subsidiary level, as a finished POC project for the entire enterprise Typically, the project results in several important “side effects” Improved data quality Improved employee job satisfaction, as they are able to proactively contribute to the central knowledge about fraud patterns in the organization Because eventually more minds get to be involved in the enterprise, the company should expect more and better fraud detection patterns After the POC project is completed as described above, the actual project would not need months of engagement from my side. This is possible due to our preference to transfer the knowledge onto the customer’s employees: typically, the customer will use the results of the POC project for some time, and only engage me again to complete the project, or to ask for additional expertise if the complexity of the problem increases significantly. I usually expect to perform the following tasks: Establish the final infrastructure to measure the efficiency of the deployed models Deploy the models in additional scenarios Through reports By including Data Mining Extensions (DMX) queries in OLTP applications to support real-time early warnings Include data mining models as dimensions in OLAP cubes, if this was not done already during the POC project Create smart ETL applications that divert suspicious data for immediate or later inspection I would also offer to investigate how the outcome could be transferred automatically to the central system; for instance, if the POC project was performed in a subsidiary whereas a central system is available as well Of course, for the actual project, I would repeat the data and model preparation as needed It is virtually impossible to tell in advance how much time the deployment would take, before we decide together with customer what exactly the deployment process should cover. Without considering the deployment part, and with the POC project conducted as suggested above (including the transfer of knowledge), the actual project should still only take additional 5 to 10 days. The approximate timeline for the POC project is, as follows: 1-2 days of training 2-3 days for data preparation and data overview 2 days for creating and evaluating the models 1 day for initial preparation of the continuous learning infrastructure 1 day for presentation of the results and discussion of further actions Quite frequently I receive the following question: are we going to find the best possible model during the POC project, or during the actual project? My answer is always quite simple: I do not know. Maybe, if we would spend just one hour more for data preparation, or create just one more model, we could get better patterns and predictions. However, we simply must stop somewhere, and the best possible way to do this, according to my experience, is to restrict the time spent on the project in advance, after an agreement with the customer. You must also never forget that, because we build the complete learning infrastructure and transfer the knowledge, the customer will be capable of doing further investigations independently and improve the models and predictions over time without the need for a constant engagement with me.

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• Given an XML which contains a representation of a graph, how to apply it DFS algorithm? [on hold]

  - by winston smith

  Given the followin XML which is a directed graph: <?xml version="1.0" encoding="iso-8859-1" ?> <!DOCTYPE graph PUBLIC "-//FC//DTD red//EN" "../dtd/graph.dtd"> <graph direct="1"> <vertex label="V0"/> <vertex label="V1"/> <vertex label="V2"/> <vertex label="V3"/> <vertex label="V4"/> <vertex label="V5"/> <edge source="V0" target="V1" weight="1"/> <edge source="V0" target="V4" weight="1"/> <edge source="V5" target="V2" weight="1"/> <edge source="V5" target="V4" weight="1"/> <edge source="V1" target="V2" weight="1"/> <edge source="V1" target="V3" weight="1"/> <edge source="V1" target="V4" weight="1"/> <edge source="V2" target="V3" weight="1"/> </graph> With this classes i parsed the graph and give it an adjacency list representation: import java.io.IOException; import java.util.HashSet; import java.util.LinkedList; import java.util.Collection; import java.util.Iterator; import java.util.logging.Level; import java.util.logging.Logger; import practica3.util.Disc; public class ParsingXML { public static void main(String[] args) { try { // TODO code application logic here Collection<Vertex> sources = new HashSet<Vertex>(); LinkedList<String> lines = Disc.readFile("xml/directed.xml"); for (String lin : lines) { int i = Disc.find(lin, "source=\""); String data = ""; if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } Vertex v = new Vertex(); v.setName(data); v.setAdy(new HashSet<Vertex>()); sources.add(v); } } Iterator it = sources.iterator(); while (it.hasNext()) { Vertex ver = (Vertex) it.next(); Collection<Vertex> adyacencias = ver.getAdy(); LinkedList<String> ls = Disc.readFile("xml/graphs.xml"); for (String lin : ls) { int i = Disc.find(lin, "target=\""); String data = ""; if (lin.contains("source=\""+ver.getName())) { Vertex v = new Vertex(); if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } v.setName(data); } i = Disc.find(lin, "weight=\""); data = ""; if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } v.setWeight(Integer.parseInt(data)); } if (v.getName() != null) { adyacencias.add(v); } } } } for (Vertex vert : sources) { System.out.println(vert); System.out.println("adyacencias: " + vert.getAdy()); } } catch (IOException ex) { Logger.getLogger(ParsingXML.class.getName()).log(Level.SEVERE, null, ex); } } } This is another class: import java.util.Collection; import java.util.Objects; public class Vertex { private String name; private int weight; private Collection ady; public Collection getAdy() { return ady; } public void setAdy(Collection adyacencias) { this.ady = adyacencias; } public String getName() { return name; } public void setName(String nombre) { this.name = nombre; } public int getWeight() { return weight; } public void setWeight(int weight) { this.weight = weight; } @Override public int hashCode() { int hash = 7; hash = 43 * hash + Objects.hashCode(this.name); hash = 43 * hash + this.weight; return hash; } @Override public boolean equals(Object obj) { if (obj == null) { return false; } if (getClass() != obj.getClass()) { return false; } final Vertex other = (Vertex) obj; if (!Objects.equals(this.name, other.name)) { return false; } if (this.weight != other.weight) { return false; } return true; } @Override public String toString() { return "Vertice{" + "name=" + name + ", weight=" + weight + '}'; } } And finally: /** * * @author user */ /* -*-jde-*- */ /* <Disc.java> Contains the main argument*/ import java.io.*; import java.util.LinkedList; /** * Lectura y escritura de archivos en listas de cadenas * Ideal para el uso de las clases para gráficas. * * @author Peralta Santa Anna Victor Miguel * @since Julio 2011 */ public class Disc { /** * Metodo para lectura de un archivo * * @param fileName archivo que se va a leer * @return El archivo en representacion de lista de cadenas */ public static LinkedList<String> readFile(String fileName) throws IOException { BufferedReader file = new BufferedReader(new FileReader(fileName)); LinkedList<String> textlist = new LinkedList<String>(); while (file.ready()) { textlist.add(file.readLine().trim()); } file.close(); /* for(String linea:textlist){ if(linea.contains("source")){ //String generado = linea.replaceAll("<\\w+\\s+\"", ""); //System.out.println(generado); } }*/ return textlist; }//readFile public static int find(String linea,String palabra){ int i,j; boolean found = false; for(i=0,j=0;i<linea.length();i++){ if(linea.charAt(i)==palabra.charAt(j)){ j++; if(j==palabra.length()){ found = true; return i; } }else{ continue; } } if(!found){ i= -1; } return i; } /** * Metodo para la escritura de un archivo * * @param fileName archivo que se va a escribir * @param tofile la lista de cadenas que quedaran en el archivo * @param append el bit que dira si se anexa el contenido o se empieza de cero */ public static void writeFile(String fileName, LinkedList<String> tofile, boolean append) throws IOException { FileWriter file = new FileWriter(fileName, append); for (int i = 0; i < tofile.size(); i++) { file.write(tofile.get(i) + "\n"); } file.close(); }//writeFile /** * Metodo para escritura de un archivo * @param msg archivo que se va a escribir * @param tofile la cadena que quedaran en el archivo * @param append el bit que dira si se anexa el contenido o se empieza de cero */ public static void writeFile(String msg, String tofile, boolean append) throws IOException { FileWriter file = new FileWriter(msg, append); file.write(tofile); file.close(); }//writeFile }// I'm stuck on what can be the best way to given an adjacency list representation of the graph how to apply it Depth-first search algorithm. Any idea of how to aproach to complete the task?

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• Oracle Flashback Technologies - Overview

  - by Sridhar_R-Oracle

  Oracle Flashback Technologies - IntroductionIn his May 29th 2014 blog, my colleague Joe Meeks introduced Oracle Maximum Availability Architecture (MAA) and discussed both planned and unplanned outages. Let’s take a closer look at unplanned outages. These can be caused by physical failures (e.g., server, storage, network, file deletion, physical corruption, site failures) or by logical failures – cases where all components and files are physically available, but data is incorrect or corrupt. These logical failures are usually caused by human errors or application logic errors. This blog series focuses on these logical errors – what causes them and how to address and recover from them using Oracle Database Flashback. In this introductory blog post, I’ll provide an overview of the Oracle Database Flashback technologies and will discuss the features in detail in future blog posts. Let’s get started. We are all human beings (unless a machine is reading this), and making mistakes is a part of what we do…often what we do best!  We “fat finger”, we spill drinks on keyboards, unplug the wrong cables, etc.  In addition, many of us, in our lives as DBAs or developers, must have observed, caused, or corrected one or more of the following unpleasant events: Accidentally updated a table with wrong values !! Performed a batch update that went wrong - due to logical errors in the code !! Dropped a table !! How do DBAs typically recover from these types of errors? First, data needs to be restored and recovered to the point-in-time when the error occurred (incomplete or point-in-time recovery).  Moreover, depending on the type of fault, it’s possible that some services – or even the entire database – would have to be taken down during the recovery process.Apart from error conditions, there are other questions that need to be addressed as part of the investigation. For example, what did the data look like in the morning, prior to the error? What were the various changes to the row(s) between two timestamps? Who performed the transaction and how can it be reversed?  Oracle Database includes built-in Flashback technologies, with features that address these challenges and questions, and enable you to perform faster, easier, and convenient recovery from logical corruptions. HistoryFlashback Query, the first Flashback Technology, was introduced in Oracle 9i. It provides a simple, powerful and completely non-disruptive mechanism for data verification and recovery from logical errors, and enables users to view the state of data at a previous point in time.Flashback Technologies were further enhanced in Oracle 10g, to provide fast, easy recovery at the database, table, row, and even at a transaction level.Oracle Database 11g introduced an innovative method to manage and query long-term historical data with Flashback Data Archive. The 11g release also introduced Flashback Transaction, which provides an easy, one-step operation to back out a transaction. Oracle Database versions 11.2.0.2 and beyond further enhanced the performance of these features. Note that all the features listed here work without requiring any kind of restore operation.In addition, Flashback features are fully supported with the new multi-tenant capabilities introduced with Oracle Database 12c, Flashback Features Oracle Flashback Database enables point-in-time-recovery of the entire database without requiring a traditional restore and recovery operation. It rewinds the entire database to a specified point in time in the past by undoing all the changes that were made since that time.Oracle Flashback Table enables an entire table or a set of tables to be recovered to a point in time in the past.Oracle Flashback Drop enables accidentally dropped tables and all dependent objects to be restored.Oracle Flashback Query enables data to be viewed at a point-in-time in the past. This feature can be used to view and reconstruct data that was lost due to unintentional change(s) or deletion(s). This feature can also be used to build self-service error correction into applications, empowering end-users to undo and correct their errors.Oracle Flashback Version Query offers the ability to query the historical changes to data between two points in time or system change numbers (SCN) Oracle Flashback Transaction Query enables changes to be examined at the transaction level. This capability can be used to diagnose problems, perform analysis, audit transactions, and even revert the transaction by undoing SQLOracle Flashback Transaction is a procedure used to back-out a transaction and its dependent transactions.Flashback technologies eliminate the need for a traditional restore and recovery process to fix logical corruptions or make enquiries. Using these technologies, you can recover from the error in the same amount of time it took to generate the error. All the Flashback features can be accessed either via SQL command line (or) via Enterprise Manager.  Most of the Flashback technologies depend on the available UNDO to retrieve older data. The following table describes the various Flashback technologies: their purpose, dependencies and situations where each individual technology can be used.   Example Syntax Error investigation related:The purpose is to investigate what went wrong and what the values were at certain points in timeFlashback Queries  ( select .. as of SCN | Timestamp )   - Helps to see the value of a row/set of rows at a point in timeFlashback Version Queries  ( select .. versions between SCN | Timestamp and SCN | Timestamp)  - Helps determine how the value evolved between certain SCNs or between timestamps Flashback Transaction Queries (select .. XID=)   - Helps to understand how the transaction caused the changes.Error correction related:The purpose is to fix the error and correct the problems,Flashback Table  (flashback table .. to SCN | Timestamp)  - To rewind the table to a particular timestamp or SCN to reverse unwanted updates Flashback Drop (flashback table ..  to before drop )  - To undrop or undelete a table Flashback Database (flashback database to SCN  | Restore Point )  - This is the rewind button for Oracle databases. You can revert the entire database to a particular point in time. It is a fast way to perform a PITR (point-in-time recovery). Flashback Transaction (DBMS_FLASHBACK.TRANSACTION_BACKOUT(XID..))  - To reverse a transaction and its related transactions Advanced use cases Flashback technology is integrated into Oracle Recovery Manager (RMAN) and Oracle Data Guard. So, apart from the basic use cases mentioned above, the following use cases are addressed using Oracle Flashback. Block Media recovery by RMAN - to perform block level recovery Snapshot Standby - where the standby is temporarily converted to a read/write environment for testing, backup, or migration purposes Re-instate old primary in a Data Guard environment – this avoids the need to restore an old backup and perform a recovery to make it a new standby. Guaranteed Restore Points - to bring back the entire database to an older point-in-time in a guaranteed way. and so on..I hope this introductory overview helps you understand how Flashback features can be used to investigate and recover from logical errors.  As mentioned earlier, I will take a deeper-dive into to some of the critical Flashback features in my upcoming blogs and address common use cases.

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• Elegance, thy Name is jQuery

  - by SGWellens

  So, I'm browsing though some questions over on the Stack Overflow website and I found a good jQuery question just a few minutes old. Here is a link to it. It was a tough question; I knew that by answering it, I could learn new stuff and reinforce what I already knew: Reading is good, doing is better. Maybe I could help someone in the process too. I cut and pasted the HTML from the question into my Visual Studio IDE and went back to Stack Overflow to reread the question. Dang, someone had already answered it! And it was a great answer. I never even had a chance to start analyzing the issue. Now I know what a one-legged man feels like in an ass-kicking contest. Nevertheless, since the question and answer were so interesting, I decided to dissect them and learn as much as possible. The HTML consisted of some divs separated by h3 headings.  Note the elements are laid out sequentially with no programmatic grouping: <h3 class="heading">Heading 1</h3> <div>Content</div> <div>More content</div> <div>Even more content</div><h3 class="heading">Heading 2</h3> <div>some content</div> <div>some more content</div><h3 class="heading">Heading 3</h3> <div>other content</div></form></body>  The requirement was to wrap a div around each h3 heading and the subsequent divs grouping them into sections. Why? I don't know, I suppose if you screen-scrapped some HTML from another site, you might want to reformat it before displaying it on your own. Anyways… Here is the marvelously, succinct posted answer: $('.heading').each(function(){ $(this).nextUntil('.heading').andSelf().wrapAll('<div class="section">');}); I was familiar with all the parts except for nextUntil and andSelf. But, I'll analyze the whole answer for completeness. I'll do this by rewriting the posted answer in a different style and adding a boat-load of comments: function Test(){ // $Sections is a jQuery object and it will contain three elements var $Sections = $('.heading'); // use each to iterate over each of the three elements $Sections.each(function () { // $this is a jquery object containing the current element // being iterated var $this = $(this); // nextUntil gets the following sibling elements until it reaches // an element with the CSS class 'heading' // andSelf adds in the source element (this) to the collection $this = $this.nextUntil('.heading').andSelf(); // wrap the elements with a div $this.wrapAll('<div class="section" >'); });}  The code here doesn't look nearly as concise and elegant as the original answer. However, unless you and your staff are jQuery masters, during development it really helps to work through algorithms step by step. You can step through this code in the debugger and examine the jQuery objects to make sure one step is working before proceeding on to the next. It's much easier to debug and troubleshoot when each logical coding step is a separate line of code. Note: You may think the original code runs much faster than this version. However, the time difference is trivial: Not enough to worry about: Less than 1 millisecond (tested in IE and FF). Note: You may want to jam everything into one line because it results in less traffic being sent to the client. That is true. However, most Internet servers now compress HTML and JavaScript by stripping out comments and white space (go to Bing or Google and view the source). This feature should be enabled on your server: Let the server compress your code, you don't need to do it. Free Career Advice: Creating maintainable code is Job One—Maximum Priority—The Prime Directive. If you find yourself suddenly transferred to customer support, it may be that the code you are writing is not as readable as it could be and not as readable as it should be. Moving on… I created a CSS class to enhance the results: .section{ background-color: yellow; border: 2px solid black; margin: 5px;} Here is the rendered output before:   …and after the jQuery code runs.   Pretty Cool! But, while playing with this code, the logic of nextUntil began to bother me: What happens in the last section? What stops elements from being collected since there are no more elements with the .heading class? The answer is nothing.  In this case it stopped collecting elements because it was at the end of the page.  But what if there were additional HTML elements? I added an anchor tag and another div to the HTML: <h3 class="heading">Heading 1</h3> <div>Content</div> <div>More content</div> <div>Even more content</div><h3 class="heading">Heading 2</h3> <div>some content</div> <div>some more content</div><h3 class="heading">Heading 3</h3> <div>other content</div><a>this is a link</a><div>unrelated div</div> </form></body> The code as-is will include both the anchor and the unrelated div. This isn't what we want.   My first attempt to correct this used the filter parameter of the nextUntil function: nextUntil('.heading', 'div')  This will only collect div elements. But it merely skipped the anchor tag and it still collected the unrelated div:   The problem is we need a way to tell the nextUntil function when to stop. CSS selectors to the rescue! nextUntil('.heading, a')  This tells nextUntil to stop collecting elements when it gets to an element with a .heading class OR when it gets to an anchor tag. In this case it solved the problem. FYI: The comma operator in a CSS selector allows multiple criteria.   Bingo! One final note, we could have broken the code down even more: We could have replaced the andSelf function here: $this = $this.nextUntil('.heading, a').andSelf(); With this: // get all the following siblings and then add the current item$this = $this.nextUntil('.heading, a');$this.add(this);  But in this case, the andSelf function reads real nice. In my opinion. Here's a link to a jsFiddle if you want to play with it. I hope someone finds this useful Steve Wellens CodeProject

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• Rebuilding CoasterBuzz, Part III: The architecture using the "Web stack of love"

  - by Jeff

  This is the third post in a series about rebuilding one of my Web sites, which has been around for 12 years. I hope to relaunch in the next month or two. More: Part I: Evolution, and death to WCF Part II: Hot data objects I finally hit a point in the re-do of CoasterBuzz where I feel like the major pieces are in place... rewritten, ported and what not, so that I can focus now on front-end design and more interesting creative problems. I've been asked on more than one occasion (OK, just twice) what's going on under the covers, so I figure this might be a good time to explain the overall architecture. As it turns out, I'm using a whole lof of the "Web stack of love," as Scott Hanselman likes to refer to it. Oh that Hanselman. First off, at the center of it all, is BizTalk. Just kidding. That's "enterprise architecture" humor, where every discussion starts with how they'll use BizTalk. Here are the bigger moving parts: It's fairly straight forward. A common library lives in a number of Web apps, all of which are (or will be) powered by ASP.NET MVC 4. They all talk to the same database. There is the main Web site, which also has the endpoint for the Silverlight-based Feed app. The cstr.bz site handles redirects, which are generated when news items are published and sent to Twitter. Facebook publishing is handled via the RSS Graffiti Facebook app. The API site handles requests from the Windows Phone app. The main site depends very heavily on POP Forums, the open source, MVC-based forum I maintain. It serves a number of functions, primarily handling users. These user objects serve in non-forum roles to handle things like news and database contributions, maintaining track records (coaster nerd for "list of rides I've been on") and, perhaps most importantly, paid club memberships. Before I get into more specifics, note that the "glue" for everything is Ninject, the dependency injection framework. I actually prefer StructureMap these days, but I started with Ninject in POP Forums a long time ago. POP Forums has a static class, PopForumsActivation, that new's up an instance of the container, and you can call it from where ever. The downside is that the forums require Ninject in your MVC app as the default dependency resolver. At some point, I'll decouple it, but for now it's not in the way. In the general sense, the entire set of apps follow a repository-service-controller-view pattern. Repos just do data access, service classes do business logic, controllers compose and route, views view. The forum also provides Scoring Game functionality. The Scoring Game is a reasonably abstract framework to award users points based on certain actions, and then award achievements when a certain number of point events happen. For example, the forum already awards a point when someone plus-one's a post you made. You can set up an achievement that says, "Give the user an award when they've had 100 posts plus'd." It also does zero-point entries into the ledger, so if you make a post, you could award an achievement based on 100 posts made. Wiring in the scoring game to CoasterBuzz functionality is just a matter of going to the Ninject container and getting an instance of the event publisher, and passing it events. Forum adapters were introduced into POP Forums a few versions ago, and they can intercept the model generated for forum topic lists and threads and designate an alternate view. These are used to make the "Day in Pictures" forum, where users can upload photos as frame-by-frame photo threads. Another adapter adds an association UI, so users can associate specific amusement parks with their trip report posts. The Silverlight-based Feed app talks to a simple JSON endpoint in the main app. This uses an underlying library I wrote ages ago, simply called Feeds, that aggregates event information. You inherit from a base class that creates instances of a publisher interface, and then use that class to send it an event type and any number of data fields. Feeds has two publishers: One is to the database, and that's used for the endpoint that talks to the Silverlight app. The second publisher publishes to Twitter, if the event is of the type "news." The wiring is a little strange, because for the new posts and topics events, I'm actually pulling out the forum repository classes from the Ninject container and replacing them with overridden methods to publish. I should probably be doing this at the service class level, but whatever. It's my mess. cstr.bz doesn't do anything interesting. It looks up the path, and if it has a match, does a 301 redirect to the long URL. The API site just serves up JSON for the Windows Phone app. The Windows Phone app is Silverlight, of course, and there isn't much to it. It does use the control toolkit, but beyond that, it relies on a simple class that creates a Webclient and calls the server for JSON to deserialize. The same class is now used by the Feed app, which used to use WCF. Simple is better. Data access in POP Forums is all straight SQL, because a lot of it was ported from the ASP.NET version. Most CoasterBuzz data access is handled by the Entity Framework, using the code-first model. The context class in this case does a lot of work to make sure that the table and key mapping works, since much of it breaks from the normal conventions of EF. One of the more powerful things you can do with EF, once you understand the little gotchas, is split tables by row into different entities. For example, a roller coaster photo has everything in the same row, including the metadata, the thumbnail bytes and the image itself. Obviously, if you want to get a list of photos to iterate over in a view, you don't want to get the image data. The use of navigation properties makes it easier to get just what you want. The front end includes Razor views in MVC, and jQuery is used for client-side goodness. I'm also using jQuery UI in a few places, for tabs, a dialog box and autocomplete. I'm also, tentatively, using jQuery Mobile. I've already ported most forum views to Mobile, but they need some work as v1.1 isn't finished yet. I'm not sure if I'll ship CoasterBuzz with mobile views or not yet. It's on the radar, but not something in my delivery criteria. That covers all of the big frameworks in play. Next time I hope to talk more about the front-end experience, which to me is where most of the fun is these days. Hoping to launch in the next month or two. Getting tired of looking at the old site!

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• Refactoring a Single Rails Model with large methods & long join queries trying to do everything

  - by Kelseydh

  I have a working Ruby on Rails Model that I suspect is inefficient, hard to maintain, and full of unnecessary SQL join queries. I want to optimize and refactor this Model (Quiz.rb) to comply with Rails best practices, but I'm not sure how I should do it. The Rails app is a game that has Missions with many Stages. Users complete Stages by answering Questions that have correct or incorrect Answers. When a User tries to complete a stage by answering questions, the User gets a Quiz entry with many Attempts. Each Attempt records an Answer submitted for that Question within the Stage. A user completes a stage or mission by getting every Attempt correct, and their progress is tracked by adding a new entry to the UserMission & UserStage join tables. All of these features work, but unfortunately the Quiz.rb Model has been twisted to handle almost all of it exclusively. The callbacks began at 'Quiz.rb', and because I wasn't sure how to leave the Quiz Model during a multi-model update, I resorted to using Rails Console to have the @quiz instance variable via self.some_method do all the heavy lifting to retrieve every data value for the game's business logic; resulting in large extended join queries that "dance" all around the Database schema. The Quiz.rb Model that Smells: class Quiz < ActiveRecord::Base belongs_to :user has_many :attempts, dependent: :destroy before_save :check_answer before_save :update_user_mission_and_stage accepts_nested_attributes_for :attempts, :reject_if => lambda { |a| a[:answer_id].blank? }, :allow_destroy => true #Checks every answer within each quiz, adding +1 for each correct answer #within a stage quiz, and -1 for each incorrect answer def check_answer stage_score = 0 self.attempts.each do |attempt| if attempt.answer.correct? == true stage_score += 1 elsif attempt.answer.correct == false stage_score - 1 end end stage_score end def winner return true end def update_user_mission_and_stage ####### #Step 1: Checks if UserMission exists, finds or creates one. #if no UserMission for the current mission exists, creates a new UserMission if self.user_has_mission? == false @user_mission = UserMission.new(user_id: self.user.id, mission_id: self.current_stage.mission_id, available: true) @user_mission.save else @user_mission = self.find_user_mission end ####### #Step 2: Checks if current UserStage exists, stops if true to prevent duplicate entry if self.user_has_stage? @user_mission.save return true else ####### ##Step 3: if step 2 returns false: ##Initiates UserStage creation instructions #checks for winner (winner actions need to be defined) if they complete last stage of last mission for a given orientation if self.passed? && self.is_last_stage? && self.is_last_mission? create_user_stage_and_update_user_mission self.winner #NOTE: The rest are the same, but specify conditions that are available to add badges or other actions upon those conditions occurring: ##if user completes first stage of a mission elsif self.passed? && self.is_first_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first stage of first mission self.user.add_badge(5) self.user.activity_logs.create(description: "granted first-stage badge", type_event: "badge", value: "first-stage") #If user completes last stage of a given mission, creates a new UserMission elsif self.passed? && self.is_last_stage? && self.is_first_mission? create_user_stage_and_update_user_mission #creates user badge for finishing first mission self.user.add_badge(6) self.user.activity_logs.create(description: "granted first-mission badge", type_event: "badge", value: "first-mission") elsif self.passed? create_user_stage_and_update_user_mission else self.passed? == false return true end end end #Creates a new UserStage record in the database for a successful Quiz question passing def create_user_stage_and_update_user_mission @nu_stage = @user_mission.user_stages.new(user_id: self.user.id, stage_id: self.current_stage.id) @nu_stage.save @user_mission.save self.user.add_points(50) end #Boolean that defines passing a stage as answering every question in that stage correct def passed? self.check_answer >= self.number_of_questions end #Returns the number of questions asked for that stage's quiz def number_of_questions self.attempts.first.answer.question.stage.questions.count end #Returns the current_stage for the Quiz, routing through 1st attempt in that Quiz def current_stage self.attempts.first.answer.question.stage end #Gives back the position of the stage relative to its mission. def stage_position self.attempts.first.answer.question.stage.position end #will find the user_mission for the current user and stage if it exists def find_user_mission self.user.user_missions.find_by_mission_id(self.current_stage.mission_id) end #Returns true if quiz was for the last stage within that mission #helpful for triggering actions related to a user completing a mission def is_last_stage? self.stage_position == self.current_stage.mission.stages.last.position end #Returns true if quiz was for the first stage within that mission #helpful for triggering actions related to a user completing a mission def is_first_stage? self.stage_position == self.current_stage.mission.stages_ordered.first.position end #Returns true if current user has a UserMission for the current stage def user_has_mission? self.user.missions.ids.include?(self.current_stage.mission.id) end #Returns true if current user has a UserStage for the current stage def user_has_stage? self.user.stages.include?(self.current_stage) end #Returns true if current user is on the last mission based on position within a given orientation def is_first_mission? self.user.missions.first.orientation.missions.by_position.first.position == self.current_stage.mission.position end #Returns true if current user is on the first stage & mission of a given orientation def is_last_mission? self.user.missions.first.orientation.missions.by_position.last.position == self.current_stage.mission.position end end My Question Currently my Rails server takes roughly 500ms to 1 sec to process single @quiz.save action. I am confident that the slowness here is due to sloppy code, not bad Database ERD design. What does a better solution look like? And specifically: Should I use join queries to retrieve values like I did here, or is it better to instantiate new objects within the model instead? Or am I missing a better solution? How should update_user_mission_and_stage be refactored to follow best practices? Relevant Code for Reference: quizzes_controller.rb w/ Controller Route Initiating Callback: class QuizzesController < ApplicationController before_action :find_stage_and_mission before_action :find_orientation before_action :find_question def show end def create @user = current_user @quiz = current_user.quizzes.new(quiz_params) if @quiz.save if @quiz.passed? if @mission.next_mission.nil? && @stage.next_stage.nil? redirect_to root_path, notice: "Congratulations, you have finished the last mission!" elsif @stage.next_stage.nil? redirect_to [@mission.next_mission, @mission.first_stage], notice: "Correct! Time for Mission #{@mission.next_mission.position}", info: "Starting next mission" else redirect_to [@mission, @stage.next_stage], notice: "Answer Correct! You passed the stage!" end else redirect_to [@mission, @stage], alert: "You didn't get every question right, please try again." end else redirect_to [@mission, @stage], alert: "Sorry. We were unable to save your answer. Please contact the admministrator." end @questions = @stage.questions.all end private def find_stage_and_mission @stage = Stage.find(params[:stage_id]) @mission = @stage.mission end def find_question @question = @stage.questions.find_by_id params[:id] end def quiz_params params.require(:quiz).permit(:user_id, :attempt_id, {attempts_attributes: [:id, :quiz_id, :answer_id]}) end def find_orientation @orientation = @mission.orientation @missions = @orientation.missions.by_position end end Overview of Relevant ERD Database Relationships: Mission - Stage - Question - Answer - Attempt <- Quiz <- User Mission - UserMission <- User Stage - UserStage <- User Other Models: Mission.rb class Mission < ActiveRecord::Base belongs_to :orientation has_many :stages has_many :user_missions, dependent: :destroy has_many :users, through: :user_missions #SCOPES scope :by_position, -> {order(position: :asc)} def stages_ordered stages.order(:position) end def next_mission self.orientation.missions.find_by_position(self.position.next) end def first_stage next_mission.stages_ordered.first end end Stage.rb: class Stage < ActiveRecord::Base belongs_to :mission has_many :questions, dependent: :destroy has_many :user_stages, dependent: :destroy has_many :users, through: :user_stages accepts_nested_attributes_for :questions, reject_if: :all_blank, allow_destroy: true def next_stage self.mission.stages.find_by_position(self.position.next) end end Question.rb class Question < ActiveRecord::Base belongs_to :stage has_many :answers, dependent: :destroy accepts_nested_attributes_for :answers, :reject_if => lambda { |a| a[:body].blank? }, :allow_destroy => true end Answer.rb: class Answer < ActiveRecord::Base belongs_to :question has_many :attempts, dependent: :destroy end Attempt.rb: class Attempt < ActiveRecord::Base belongs_to :answer belongs_to :quiz end User.rb: class User < ActiveRecord::Base belongs_to :school has_many :activity_logs has_many :user_missions, dependent: :destroy has_many :missions, through: :user_missions has_many :user_stages, dependent: :destroy has_many :stages, through: :user_stages has_many :orientations, through: :school has_many :quizzes, dependent: :destroy has_many :attempts, through: :quizzes def latest_stage_position self.user_missions.last.user_stages.last.stage.position end end UserMission.rb class UserMission < ActiveRecord::Base belongs_to :user belongs_to :mission has_many :user_stages, dependent: :destroy end UserStage.rb class UserStage < ActiveRecord::Base belongs_to :user belongs_to :stage belongs_to :user_mission end

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• ASP.NET MVC: Using ProfileRequiredAttribute to restrict access to pages

  - by DigiMortal

  If you are using AppFabric Access Control Services to authenticate users when they log in to your community site using Live ID, Google or some other popular identity provider, you need more than AuthorizeAttribute to make sure that users can access the content that is there for authenticated users only. In this posting I will show you hot to extend the AuthorizeAttribute so users must also have user profile filled. Semi-authorized users When user is authenticated through external identity provider then not all identity providers give us user name or other information we ask users when they join with our site. What all identity providers have in common is unique ID that helps you identify the user. Example. Users authenticated through Windows Live ID by AppFabric ACS have no name specified. Google’s identity provider is able to provide you with user name and e-mail address if user agrees to publish this information to you. They both give you unique ID of user when user is successfully authenticated in their service. There is logical shift between ASP.NET and my site when considering user as authorized. For ASP.NET MVC user is authorized when user has identity. For my site user is authorized when user has profile and row in my users table. Having profile means that user has unique username in my system and he or she is always identified by this username by other users. My solution is simple: I created my own action filter attribute that makes sure if user has profile to access given method and if user has no profile then browser is redirected to join page. Illustrating the problem Usually we restrict access to page using AuthorizeAttribute. Code is something like this. [Authorize] public ActionResult Details(string id) {     var profile = _userRepository.GetUserByUserName(id);     return View(profile); } If this page is only for site users and we have user profiles then all users – the ones that have profile and all the others that are just authenticated – can access the information. It is okay because all these users have successfully logged in in some service that is supported by AppFabric ACS. In my site the users with no profile are in grey spot. They are on half way to be users because they have no username and profile on my site yet. So looking at the image above again we need something that adds profile existence condition to user-only content. [ProfileRequired] public ActionResult Details(string id) {     var profile = _userRepository.GetUserByUserName(id);     return View(profile); } Now, this attribute will solve our problem as soon as we implement it. ProfileRequiredAttribute: Profiles are required to be fully authorized Here is my implementation of ProfileRequiredAttribute. It is pretty new and right now it is more like working draft but you can already play with it. public class ProfileRequiredAttribute : AuthorizeAttribute {     private readonly string _redirectUrl;       public ProfileRequiredAttribute()     {         _redirectUrl = ConfigurationManager.AppSettings["JoinUrl"];         if (string.IsNullOrWhiteSpace(_redirectUrl))             _redirectUrl = "~/";     }              public override void OnAuthorization(AuthorizationContext filterContext)     {         base.OnAuthorization(filterContext);           var httpContext = filterContext.HttpContext;         var identity = httpContext.User.Identity;           if (!identity.IsAuthenticated || identity.GetProfile() == null)             if(filterContext.Result == null)                 httpContext.Response.Redirect(_redirectUrl);          } } All methods with this attribute work as follows: if user is not authenticated then he or she is redirected to AppFabric ACS identity provider selection page, if user is authenticated but has no profile then user is by default redirected to main page of site but if you have application setting with name JoinUrl then user is redirected to this URL. First case is handled by AuthorizeAttribute and the second one is handled by custom logic in ProfileRequiredAttribute class. GetProfile() extension method To get user profile using less code in places where profiles are needed I wrote GetProfile() extension method for IIdentity interface. There are some more extension methods that read out user and identity provider identifier from claims and based on this information user profile is read from database. If you take this code with copy and paste I am sure it doesn’t work for you but you get the idea. public static User GetProfile(this IIdentity identity) {     if (identity == null)         return null;       var context = HttpContext.Current;     if (context.Items["UserProfile"] != null)         return context.Items["UserProfile"] as User;       var provider = identity.GetIdentityProvider();     var nameId = identity.GetNameIdentifier();       var rep = ObjectFactory.GetInstance<IUserRepository>();     var profile = rep.GetUserByProviderAndNameId(provider, nameId);       context.Items["UserProfile"] = profile;       return profile; } To avoid round trips to database I cache user profile to current request because the chance that profile gets changed meanwhile is very minimal. The other reason is maybe more tricky – profile objects are coming from Entity Framework context and context has also HTTP request as lifecycle. Conclusion This posting gave you some ideas how to finish user profiles stuff when you use AppFabric ACS as external authentication provider. Although there was little shift between us and ASP.NET MVC with interpretation of “authorized” we were easily able to solve the problem by extending AuthorizeAttribute to get all our requirements fulfilled. We also write extension method for IIdentity that returns as user profile based on username and caches the profile in HTTP request scope.

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• Set Context User Principal for Customized Authentication in SignalR

  - by Shaun

  Originally posted on: http://geekswithblogs.net/shaunxu/archive/2014/05/27/set-context-user-principal-for-customized-authentication-in-signalr.aspxCurrently I'm working on a single page application project which is built on AngularJS and ASP.NET WebAPI. When I need to implement some features that needs real-time communication and push notifications from server side I decided to use SignalR. SignalR is a project currently developed by Microsoft to build web-based, read-time communication application. You can find it here. With a lot of introductions and guides it's not a difficult task to use SignalR with ASP.NET WebAPI and AngularJS. I followed this and this even though it's based on SignalR 1. But when I tried to implement the authentication for my SignalR I was struggled 2 days and finally I got a solution by myself. This might not be the best one but it actually solved all my problem.   In many articles it's said that you don't need to worry about the authentication of SignalR since it uses the web application authentication. For example if your web application utilizes form authentication, SignalR will use the user principal your web application authentication module resolved, check if the principal exist and authenticated. But in my solution my ASP.NET WebAPI, which is hosting SignalR as well, utilizes OAuth Bearer authentication. So when the SignalR connection was established the context user principal was empty. So I need to authentication and pass the principal by myself.   Firstly I need to create a class which delivered from "AuthorizeAttribute", that will takes the responsible for authenticate when SignalR connection established and any method was invoked. 1: public class QueryStringBearerAuthorizeAttribute : AuthorizeAttribute 2: { 3: public override bool AuthorizeHubConnection(HubDescriptor hubDescriptor, IRequest request) 4: { 5: } 6:  7: public override bool AuthorizeHubMethodInvocation(IHubIncomingInvokerContext hubIncomingInvokerContext, bool appliesToMethod) 8: { 9: } 10: } The method "AuthorizeHubConnection" will be invoked when any SignalR connection was established. And here I'm going to retrieve the Bearer token from query string, try to decrypt and recover the login user's claims. 1: public override bool AuthorizeHubConnection(HubDescriptor hubDescriptor, IRequest request) 2: { 3: var dataProtectionProvider = new DpapiDataProtectionProvider(); 4: var secureDataFormat = new TicketDataFormat(dataProtectionProvider.Create()); 5: // authenticate by using bearer token in query string 6: var token = request.QueryString.Get(WebApiConfig.AuthenticationType); 7: var ticket = secureDataFormat.Unprotect(token); 8: if (ticket != null && ticket.Identity != null && ticket.Identity.IsAuthenticated) 9: { 10: // set the authenticated user principal into environment so that it can be used in the future 11: request.Environment["server.User"] = new ClaimsPrincipal(ticket.Identity); 12: return true; 13: } 14: else 15: { 16: return false; 17: } 18: } In the code above I created "TicketDataFormat" instance, which must be same as the one I used to generate the Bearer token when user logged in. Then I retrieve the token from request query string and unprotect it. If I got a valid ticket with identity and it's authenticated this means it's a valid token. Then I pass the user principal into request's environment property which can be used in nearly future. Since my website was built in AngularJS so the SignalR client was in pure JavaScript, and it's not support to set customized HTTP headers in SignalR JavaScript client, I have to pass the Bearer token through request query string. This is not a restriction of SignalR, but a restriction of WebSocket. For security reason WebSocket doesn't allow client to set customized HTTP headers from browser. Next, I need to implement the authentication logic in method "AuthorizeHubMethodInvocation" which will be invoked when any SignalR method was invoked. 1: public override bool AuthorizeHubMethodInvocation(IHubIncomingInvokerContext hubIncomingInvokerContext, bool appliesToMethod) 2: { 3: var connectionId = hubIncomingInvokerContext.Hub.Context.ConnectionId; 4: // check the authenticated user principal from environment 5: var environment = hubIncomingInvokerContext.Hub.Context.Request.Environment; 6: var principal = environment["server.User"] as ClaimsPrincipal; 7: if (principal != null && principal.Identity != null && principal.Identity.IsAuthenticated) 8: { 9: // create a new HubCallerContext instance with the principal generated from token 10: // and replace the current context so that in hubs we can retrieve current user identity 11: hubIncomingInvokerContext.Hub.Context = new HubCallerContext(new ServerRequest(environment), connectionId); 12: return true; 13: } 14: else 15: { 16: return false; 17: } 18: } Since I had passed the user principal into request environment in previous method, I can simply check if it exists and valid. If so, what I need is to pass the principal into context so that SignalR hub can use. Since the "User" property is all read-only in "hubIncomingInvokerContext", I have to create a new "ServerRequest" instance with principal assigned, and set to "hubIncomingInvokerContext.Hub.Context". After that, we can retrieve the principal in my Hubs through "Context.User" as below. 1: public class DefaultHub : Hub 2: { 3: public object Initialize(string host, string service, JObject payload) 4: { 5: var connectionId = Context.ConnectionId; 6: ... ... 7: var domain = string.Empty; 8: var identity = Context.User.Identity as ClaimsIdentity; 9: if (identity != null) 10: { 11: var claim = identity.FindFirst("Domain"); 12: if (claim != null) 13: { 14: domain = claim.Value; 15: } 16: } 17: ... ... 18: } 19: } Finally I just need to add my "QueryStringBearerAuthorizeAttribute" into the SignalR pipeline. 1: app.Map("/signalr", map => 2: { 3: // Setup the CORS middleware to run before SignalR. 4: // By default this will allow all origins. You can 5: // configure the set of origins and/or http verbs by 6: // providing a cors options with a different policy. 7: map.UseCors(CorsOptions.AllowAll); 8: var hubConfiguration = new HubConfiguration 9: { 10: // You can enable JSONP by uncommenting line below. 11: // JSONP requests are insecure but some older browsers (and some 12: // versions of IE) require JSONP to work cross domain 13: // EnableJSONP = true 14: EnableJavaScriptProxies = false 15: }; 16: // Require authentication for all hubs 17: var authorizer = new QueryStringBearerAuthorizeAttribute(); 18: var module = new AuthorizeModule(authorizer, authorizer); 19: GlobalHost.HubPipeline.AddModule(module); 20: // Run the SignalR pipeline. We're not using MapSignalR 21: // since this branch already runs under the "/signalr" path. 22: map.RunSignalR(hubConfiguration); 23: }); On the client side should pass the Bearer token through query string before I started the connection as below. 1: self.connection = $.hubConnection(signalrEndpoint); 2: self.proxy = self.connection.createHubProxy(hubName); 3: self.proxy.on(notifyEventName, function (event, payload) { 4: options.handler(event, payload); 5: }); 6: // add the authentication token to query string 7: // we cannot use http headers since web socket protocol doesn't support 8: self.connection.qs = { Bearer: AuthService.getToken() }; 9: // connection to hub 10: self.connection.start(); Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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• Deterministic/Consistent Unique Masking

  - by Dinesh Rajasekharan-Oracle

  One of the key requirements while masking data in large databases or multi database environment is to consistently mask some columns, i.e. for a given input the output should always be the same. At the same time the masked output should not be predictable. Deterministic masking also eliminates the need to spend enormous amount of time spent in identifying data relationships, i.e. parent and child relationships among columns defined in the application tables. In this blog post I will explain different ways of consistently masking the data across databases using Oracle Data Masking and Subsetting The readers of post should have minimal knowledge on Oracle Enterprise Manager 12c, Application Data Modeling, Data Masking concepts. For more information on these concepts, please refer to Oracle Data Masking and Subsetting document Oracle Data Masking and Subsetting 12c provides four methods using which users can consistently yet irreversibly mask their inputs. 1. Substitute 2. SQL Expression 3. Encrypt 4. User Defined Function SUBSTITUTE The substitute masking format replaces the original value with a value from a pre-created database table. As the method uses a hash based algorithm in the back end the mappings are consistent. For example consider DEPARTMENT_ID in EMPLOYEES table is replaced with FAKE_DEPARTMENT_ID from FAKE_TABLE. The substitute masking transformation that all occurrences of DEPARTMENT_ID say ‘101’ will be replaced with ‘502’ provided same substitution table and column is used , i.e. FAKE_TABLE.FAKE_DEPARTMENT_ID. The following screen shot shows the usage of the Substitute masking format with in a masking definition: Note that the uniqueness of the masked value depends on the number of columns being used in the substitution table i.e. if the original table contains 50000 unique values, then for the masked output to be unique and deterministic the substitution column should also contain 50000 unique values without which only consistency is maintained but not uniqueness. SQL EXPRESSION SQL Expression replaces an existing value with the output of a specified SQL Expression. For example while masking an EMPLOYEES table the EMAIL_ID of an employee has to be in the format EMPLOYEE’s [email protected] while FIRST_NAME and LAST_NAME are the actual column names of the EMPLOYEES table then the corresponding SQL Expression will look like %FIRST_NAME%||’.’||%LAST_NAME%||’@COMPANY.COM’. The advantage of this technique is that if you are masking FIRST_NAME and LAST_NAME of the EMPLOYEES table than the corresponding EMAIL ID will be replaced accordingly by the masking scripts. One of the interesting aspect’s of a SQL Expressions is that you can use sub SQL expressions, which means that you can write a nested SQL and use it as SQL Expression to address a complex masking business use cases. SQL Expression can also be used to consistently replace value with hashed value using Oracle’s PL/SQL function ORA_HASH. The following SQL Expression will help in the previous example for replacing the DEPARTMENT_IDs with a hashed number ORA_HASH (%DEPARTMENT_ID%, 1000) The following screen shot shows the usage of encrypt masking format with in the masking definition: ORA_HASH takes three arguments: 1. Expression which can be of any data type except LONG, LOB, User Defined Type [nested table type is allowed]. In the above example I used the Original value as expression. 2. Number of hash buckets which can be number between 0 and 4294967295. The default value is 4294967295. You can also co-relate the number of hash buckets to a range of numbers. In the above example above the bucket value is specified as 1000, so the end result will be a hashed number in between 0 and 1000. 3. Seed, can be any number which decides the consistency, i.e. for a given seed value the output will always be same. The default seed is 0. In the above SQL Expression a seed in not specified, so it to 0. If you have to use a non default seed then the function will look like. ORA_HASH (%DEPARTMENT_ID%, 1000, 1234 The uniqueness depends on the input and the number of hash buckets used. However as ORA_HASH uses a 32 bit algorithm, considering birthday paradox or pigeonhole principle there is a 0.5 probability of collision after 232-1 unique values. ENCRYPT Encrypt masking format uses a blend of 3DES encryption algorithm, hashing, and regular expression to produce a deterministic and unique masked output. The format of the masked output corresponds to the specified regular expression. As this technique uses a key [string] to encrypt the data, the same string can be used to decrypt the data. The key also acts as seed to maintain consistent outputs for a given input. The following screen shot shows the usage of encrypt masking format with in the masking definition: Regular Expressions may look complex for the first time users but you will soon realize that it’s a simple language. There are many resources in internet, oracle documentation, oracle learning library, my oracle support on writing a Regular Expressions, out of all the following My Oracle Support document helped me to get started with Regular Expressions: Oracle SQL Support for Regular Expressions[Video](Doc ID 1369668.1) USER DEFINED FUNCTION [UDF] User Defined Function or UDF provides flexibility for the users to code their own masking logic in PL/SQL, which can be called from masking Defintion. The standard format of an UDF in Oracle Data Masking and Subsetting is: Function udf_func (rowid varchar2, column_name varchar2, original_value varchar2) returns varchar2; Where • rowid is the row identifier of the column that needs to be masked • column_name is the name of the column that needs to be masked • original_value is the column value that needs to be masked You can achieve deterministic masking by using Oracle’s built in hash functions like, ORA_HASH, DBMS_CRYPTO.MD4, DBMS_CRYPTO.MD5, DBMS_UTILITY. GET_HASH_VALUE.Please refers to the Oracle Database Documentation for more information on the Oracle Hash functions. For example the following masking UDF generate deterministic unique hexadecimal values for a given string input: CREATE OR REPLACE FUNCTION RD_DUX (rid varchar2, column_name varchar2, orig_val VARCHAR2) RETURN VARCHAR2 DETERMINISTIC PARALLEL_ENABLE IS stext varchar2 (26); no_of_characters number(2); BEGIN no_of_characters:=6; stext:=substr(RAWTOHEX(DBMS_CRYPTO.HASH(UTL_RAW.CAST_TO_RAW(text),1)),0,no_of_characters); RETURN stext; END; The uniqueness depends on the input and length of the string and number of bits used by hash algorithm. In the above function MD4 hash is used [denoted by argument 1 in the DBMS_CRYPTO.HASH function which is a 128 bit algorithm which produces 2^128-1 unique hashed values , however this is limited by the length of the input string which is 6, so only 6^6 unique values will be generated. Also do not forget about the birthday paradox/pigeonhole principle mentioned earlier in this post. An another example is to consistently replace characters or numbers preserving the length and special characters as shown below: CREATE OR REPLACE FUNCTION RD_DUS(rid varchar2,column_name varchar2,orig_val VARCHAR2) RETURN VARCHAR2 DETERMINISTIC PARALLEL_ENABLE IS stext varchar2(26); BEGIN DBMS_RANDOM.SEED(orig_val); stext:=TRANSLATE(orig_val,'ABCDEFGHILKLMNOPQRSTUVWXYZ',DBMS_RANDOM.STRING('U',26)); stext:=TRANSLATE(stext,'abcdefghijklmnopqrstuvwxyz',DBMS_RANDOM.STRING('L',26)); stext:=TRANSLATE(stext,'0123456789',to_char(DBMS_RANDOM.VALUE(1,9))); stext:=REPLACE(stext,'.','0'); RETURN stext; END; The following screen shot shows the usage of an UDF with in a masking definition: To summarize, Oracle Data Masking and Subsetting helps you to consistently mask data across databases using one or all of the methods described in this post. It saves the hassle of identifying the parent-child relationships defined in the application table. Happy Masking

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• Need Help in optimizing a loop in C [migrated]

  - by WedaPashi

  I am trying to draw a Checkerboard pattern on a lcd using a GUI library called emWin. I have actually managed to draw it using the following code. But having these many loops in the program body for a single task, that too in the internal flash of the Microcontroller is not a good idea. Those who have not worked with emWin, I will try and explain a few things before we go for actual logic. GUI_REST is a structure which id define source files of emWin and I am blind to it. Rect, REct2,Rec3.. and so on till Rect10 are objects. Elements of the Rect array are {x0,y0,x1,y1}, where x0,y0 are starting locations of rectangle in X-Y plane and x1, y1 are end locations of Rectangle in x-Y plane. So, Rect={0,0,79,79} is a rectangle starts at top left of the LCD and is upto (79,79), so its a square basically. The function GUI_setBkColor(int color); sets the color of the background. The function GUI_setColor(int color); sets the color of the foreground. GUI_WHITE and DM_CHECKERBOARD_COLOR are two color values, #defineed GUI_FillRectEx(&Rect); will draw the Rectangle. The code below works fine but I want to make it smarter. GUI_RECT Rect = {0, 0, 79, 79}; GUI_RECT Rect2 = {80, 0, 159, 79}; GUI_RECT Rect3 = {160, 0, 239, 79}; GUI_RECT Rect4 = {240, 0, 319, 79}; GUI_RECT Rect5 = {320, 0, 399, 79}; GUI_RECT Rect6 = {400, 0, 479, 79}; GUI_RECT Rect7 = {480, 0, 559, 79}; GUI_RECT Rect8 = {560, 0, 639, 79}; GUI_RECT Rect9 = {640, 0, 719, 79}; GUI_RECT Rect10 = {720, 0, 799, 79}; WM_SelectWindow(Win_DM_Main); GUI_SetBkColor(GUI_BLACK); GUI_Clear(); for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect); Rect.y0 += 80; Rect.y1 += 80; } /* for(j=0,j<11;j++) { for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect); Rect.y0 += 80; Rect.y1 += 80; } Rect.x0 += 80; Rect.x1 += 80; } */ for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect2); Rect2.y0 += 80; Rect2.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect3); Rect3.y0 += 80; Rect3.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect4); Rect4.y0 += 80; Rect4.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect5); Rect5.y0 += 80; Rect5.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect6); Rect6.y0 += 80; Rect6.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect7); Rect7.y0 += 80; Rect7.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect8); Rect8.y0 += 80; Rect8.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect9); Rect9.y0 += 80; Rect9.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect10); Rect10.y0 += 80; Rect10.y1 += 80; }

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