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  • How to call Office365 web service in a Console application using WCF

    - by ybbest
    In my previous post, I showed you how to call the SharePoint web service using a console application. In this post, I’d like to show you how to call the same web service in the cloud, aka Office365.In office365, it uses claims authentication as opposed to windows authentication for normal in-house SharePoint Deployment. For Details of the explanation you can see Wictor’s post on this here. The key to make it work is to understand when you authenticate from Office365, you get your authentication token. You then need to pass this token to your HTTP request as cookie to make the web service call. Here is the code sample to make it work.I have modified Wictor’s by removing the client object references. static void Main(string[] args) { MsOnlineClaimsHelper claimsHelper = new MsOnlineClaimsHelper( "[email protected]", "YourPassword","https://ybbest.sharepoint.com/"); HttpRequestMessageProperty p = new HttpRequestMessageProperty(); var cookie = claimsHelper.CookieContainer; string cookieHeader = cookie.GetCookieHeader(new Uri("https://ybbest.sharepoint.com/")); p.Headers.Add("Cookie", cookieHeader); using (ListsSoapClient proxy = new ListsSoapClient()) { proxy.Endpoint.Address = new EndpointAddress("https://ybbest.sharepoint.com/_vti_bin/Lists.asmx"); using (new OperationContextScope(proxy.InnerChannel)) { OperationContext.Current.OutgoingMessageProperties[HttpRequestMessageProperty.Name] = p; XElement spLists = proxy.GetListCollection(); foreach (var el in spLists.Descendants()) { //System.Console.WriteLine(el.Name); foreach (var attrib in el.Attributes()) { if (attrib.Name.LocalName.ToLower() == "title") { System.Console.WriteLine("> " + attrib.Name + " = " + attrib.Value); } } } } System.Console.ReadKey(); } } You can download the complete code from here. Reference: Managing shared cookies in WCF How to do active authentication to Office 365 and SharePoint Online

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  • Can't get PXE boot working on WDS + Linux DHCP server

    - by askvictor
    Hi I'm trying to get WDS to PXE boot some laptops. The university is running a (linux) DHCP server for the entire network; we can't run our own. We can (and have) set options in that DHCP server to point to a tftp server and file (pxeboot.n12 on the WDS server we run). The client seems to get the pxeboot.n12 file (judging by the server logs), but then comes back with 'TFTP download failed Pres any key to reboot'. I've tried running a third-party tftp service on the WDS server, and found that the client pulls the first stage (pxeboot.n12) correctly, but then looks for the second stage (bootmgr.exe) in the root of the tftp folder - whereas WDS places it in \boot\x86\ (or \boot\x64). Similarly, it looks for a file called BCD, which doesn't exist (rather there are a few files scattered around with the extension .bcd). I'm confused if the WDS tftp server does some magic returning certain files, or if I haven't configured it correctly. The server is 2008 R2. Cheers, Victor

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  • Bypass RDP Client Warning

    - by Butcher
    How do I bypass the security warning in the RDP Client everytime you launch it from a RDP shortcut? The message title reads: "The publisher of this remote connection cannot be identified. Do you want to connect anyway?" There's a checkbox that reads: "Don't ask me again for connections to this computer" If we check that, it rights the following registry key: [HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\LocalDevices] "MachineIP or Name"=dword:00000004 I'm trying to bypass this warning by writing this registry values before I run the RDP. The problem is that the dword value varies. I found that in one machine (Win7), it was 4, but in another machine (XP), the value was 72 decimal. Does it vary depending on your OS, or is it by the RDP client version? Other info: Signing all my RDP files is NOT an option. Checking the checkbox is NOT an option as we are trying to automate some stuff with a C# tool. Thank you

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  • Installing esx 3.5 on hpblade 460c G7

    - by stillStudent
    I was trying to install ESX 3.5 on hp blade 460c but it fails with error no 'network adapter is detected'. Anybody has work around for this. I also tried to install ESX 4.1, it also had the same problem but in case of 4.1 there is support to add your custom driver while installing. So I added NIC drivers and installation completed successfully. ESX 3.5 installtion does not support adding custom drivers while installing. I can't use ESX 4.1 because it does not support 'license server' configuration and only asks for license file(key). I do not have license keys, I only have vmware license server. That is the reason I have to be with ESX 3.5.

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  • CodePlex Daily Summary for Wednesday, March 10, 2010

    CodePlex Daily Summary for Wednesday, March 10, 2010New ProjectsASP.NET jQuery MessageBox: The ASP.NET jQuery it's an Web User Control that uses jQuery framework to enable diferent ways to present information to the user, by using these ...CommentRemover: Utility for removing comments from source codes. Support PL/SQL, Delphi, C/C#/C++ Developed in C# Requirement Microsoft .NET Framework 3.5DotNetNuke® RadMenu: DNNRadMenu makes it easy to create skins which use telerik RadMenu functionality. Licensing permits anyone (including designers) to use the compon...DotNetNuke® Skin AlphaBrisk: A DotNetNuke Design Challenge skin package submitted to the "Web Standards" category by dnnskin.net. Eight themes using transparent png, div, CSS, ...DotNetNuke® Skin Collaborate: A DotNetNuke Design Challenge skin package submitted to the "Modern Business" category by Cuong Dang of R2Integrated. This package is 100% XHTML an...DotNetNuke® Skin TR: A DotNetNuke Design Challenge skin package submitted to the "Out of the box" category by Tracy Wittenkeller of T-Worx. This package is 100% XHTML, ...Encrypted Notes: Encrypted Notes is similar to Notes, but uses Triple DES to encrypt text and files. It has a random key generator, and can save the key. It is deve...FalconLobby: FalconLobby is an authorized AddOn for Falcon 4.0 Allied Force which was created to support the multiplayer experience. FalconLobby retrieves the l...INETA Europe WebSite: Website for INETA EuropeInsert a Favorite (Bookmark) plugin for Windows Live Writer: This Windows Live Writer plugin allows you to select a Favorite (Bookmark) and insert it into your blog entry.Javascript Lib: an javascript libraryjqGrid ASP.Net MVC Control: A fully integrated ASP.Net MVC (2.0) grid control based on the successfull jqGrid plugin for the jQuery jscript framework. Among the features of...Mosaictor: Mosaictor is a per project of mine that I started halfway my education. It is a photo mosaic creator using locally saved files and files obtained t...Notes: Notes is a simple but fast text editor. It can save in many text formats, and includes many features, such as templates (soon to be customizable), ...notmuchweb: A web frontend for notmuchPervasiveID: The PID is actively involved in Open Source ID community-building and education. PID members frequently travel the world to attend ID conferences a...Proyect Electronica: Proyecto de electronicaRapidshare Downloader 2: Rapidshare Downloader 2ROAD is Rapid Oberon Application Development: A suite of integrated tools for the develpment of Oberon-2 applicationSDNTFSIntegration: TFS Integration.SilverlightImageUpload: SilverlightImageUploadSMIL - SharePoint Map Integration Layer: .Useful SharePoint Site Workflow Utilities: This project aims to make it easy use SharePoint 2010's Site Workflows as "event handlers" for various back end systems by providing ways to start ...Windows Media Autorization: Windows Media Autorizaton PlugIn for windows media 9 WinMo Twitter Widget StarterKit: This project will allow you to quickly create Widgets that run on a Windows Mobile 6.5 phone to allow you to view Tweets designated by a hash tag. ...XNA 3D World Studio Content Pipeline: XNA 3D World Studio Content Pipeline New ReleasesAPSales - CRM Software as a Service: APSales 0.1.2: This version add some interesting features to the project: Implements a Grid Control Custom View Query Use lastest version(2.0.2) of APEnnead.net ...ASP.NET jQuery MessageBox: ASP.NET jQuery MessageBox 0.1: Project Description The ASP.NET jQuery it's an Web User Control que uses jQuery framework to enable diferent ways to present information to the use...BTP Tools: CSBC+CUVC+HCSBC.dict files 2010-03-09: a space character should be only between <Strong Number Pattern> and <Count> like: <Text><Strong Number pattern><space character> <Count> The abov...Citrix HDX MediaStream for Flash System Verifier: HDX Flash Verifier Beta (v1.20): Reduced the number of exceptions that terminate the verification process.Code examples, utilities and misc from Lars Wilhelmsen [MVP]: LarsW.MexEdmxFixer 1.5: Added some missing sub elements from the EDMX file's Designer element; Connection and Output. Without them, some of the properties in the designer ...CommonLibrary.NET: CommonLibrary.NET 0.9.4 - Beta 2: A collection of very reusable code and components in C# 3.5 ranging from ActiveRecord, Csv, Command Line Parsing, Configuration, Holiday Calendars,...Encrypted Notes: Source Code: This has the all the code for Encrypted Notes in a Text file.Hybrid Windows Service: Release Assembly: Main Assembly. Usage: 1. Add reference to this dll in your 'Windows Service' project. 2. Replace references to ServiceBase to HybridServiceBase in...jqGrid ASP.Net MVC Control: Version 1.0.0.0: Initial Versionkdar: KDAR 0.0.16: KDAR - Kernel Debugger Anti Rootkit - KINTERRUPT object check added - load image notifier check addedlatex2mathml: 1.0 alpha: This is the first public release of Latex2MathML. Lots are left to add and fix. I encourage you to test it. If something goes wrong, send me the lo...MapWindow GIS: MapWindow 6.0 msi (March 9): This fixes a bug with saving and opening maps.Microsoft Research Biology Extension for Excel: MSR Biology Extension for Excel - Beta 2 (Update): This is an updated release for the Beta 2 Installer for the MSR Biology Extension for Excel. A couple of identified issues with the installation f...Notes: Notes 5.2: This is the latest version of Notes (5.2). It has an installer - it will create a directory 'CPascoe' in My Documents. Once you have extracted the...Notes: Source Code: This has the all the code for Notes in a Text file.RedBulb for XNA Framework: Tree Massacre XMAS Edition (Sample): Tree Massacre XMAS Edition Source Code and Creators Club Package http://bayimg.com/image/jalkiaacb.jpgRoTwee: RoTwee (7.0.2.0): Now color mode is introduced to RoTwee. Push change color button and you can change color mode of RoTwee. Recommended mode is active rainbow mode :)SharePoint Team-Mailer: SharePoint Team-Mailer v1.0: Recommended versionsPWadmin: pwAdmin v0.7_nightly: Nightly Build --------------------- + Target JRE -> 1.5.0_21 + Target ApplicationServer -> Apache Tomcat 5.5.28 + Added xml editor (only working fo...SQL Server PowerShell Extensions: 2.1 Production: Release 2.1 re-implements SQLPSX as PowersShell version 2.0 modules. SQLPSX consists of 9 modules with 133 advanced functions, 2 cmdlets and 7 scri...TMap for VS2010: TMap for VS2010 (MSF Agile) RC Release: Release of the TMap process template for VS2010 combined with the MSF Agile process template basd on the Release Candidate. The references to the g...TS3QueryLib.Net: TS3QueryLib.Net Version 0.19.14.0: Changelog Added property "IsClientRecording" to class "ClientListEntry" which is used in method "GetClientList" of QueryRunner class. (Change of Be...VCC: Latest build, v2.1.30309.0: Automatic drop of latest buildWinMo Twitter Widget StarterKit: Tweet Viewer Files: Files necessary to create your own Tweet ViewerWPF AutoComplete TextBox Control: Version 1.1: This release includes accumulated bug fixes since the initial release. Besides, adds experimental asynchronous support. Sample application gets...XNA 3D World Studio Content Pipeline: XNA 3DWS Content Pipeline: This is an rar file containing the latest content importer codeMost Popular ProjectsMetaSharpWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesASP.NET Ajax LibraryMost Active ProjectsUmbraco CMSRawrSDS: Scientific DataSet library and toolsjQuery Library for SharePoint Web ServicesBlogEngine.NETN2 CMSFasterflect - A Fast and Simple Reflection APIFarseer Physics Enginepatterns & practices – Enterprise LibraryCaliburn: An Application Framework for WPF and Silverlight

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  • TOTD #166: Using NoSQL database in your Java EE 6 Applications on GlassFish - MongoDB for now!

    - by arungupta
    The Java EE 6 platform includes Java Persistence API to work with RDBMS. The JPA specification defines a comprehensive API that includes, but not restricted to, how a database table can be mapped to a POJO and vice versa, provides mechanisms how a PersistenceContext can be injected in a @Stateless bean and then be used for performing different operations on the database table and write typesafe queries. There are several well known advantages of RDBMS but the NoSQL movement has gained traction over past couple of years. The NoSQL databases are not intended to be a replacement for the mainstream RDBMS. As Philosophy of NoSQL explains, NoSQL database was designed for casual use where all the features typically provided by an RDBMS are not required. The name "NoSQL" is more of a category of databases that is more known for what it is not rather than what it is. The basic principles of NoSQL database are: No need to have a pre-defined schema and that makes them a schema-less database. Addition of new properties to existing objects is easy and does not require ALTER TABLE. The unstructured data gives flexibility to change the format of data any time without downtime or reduced service levels. Also there are no joins happening on the server because there is no structure and thus no relation between them. Scalability and performance is more important than the entire set of functionality typically provided by an RDBMS. This set of databases provide eventual consistency and/or transactions restricted to single items but more focus on CRUD. Not be restricted to SQL to access the information stored in the backing database. Designed to scale-out (horizontal) instead of scale-up (vertical). This is important knowing that databases, and everything else as well, is moving into the cloud. RBDMS can scale-out using sharding but requires complex management and not for the faint of heart. Unlike RBDMS which require a separate caching tier, most of the NoSQL databases comes with integrated caching. Designed for less management and simpler data models lead to lower administration as well. There are primarily three types of NoSQL databases: Key-Value stores (e.g. Cassandra and Riak) Document databases (MongoDB or CouchDB) Graph databases (Neo4J) You may think NoSQL is panacea but as I mentioned above they are not meant to replace the mainstream databases and here is why: RDBMS have been around for many years, very stable, and functionally rich. This is something CIOs and CTOs can bet their money on without much worry. There is a reason 98% of Fortune 100 companies run Oracle :-) NoSQL is cutting edge, brings excitement to developers, but enterprises are cautious about them. Commercial databases like Oracle are well supported by the backing enterprises in terms of providing support resources on a global scale. There is a full ecosystem built around these commercial databases providing training, performance tuning, architecture guidance, and everything else. NoSQL is fairly new and typically backed by a single company not able to meet the scale of these big enterprises. NoSQL databases are good for CRUDing operations but business intelligence is extremely important for enterprises to stay competitive. RDBMS provide extensive tooling to generate this data but that was not the original intention of NoSQL databases and is lacking in that area. Generating any meaningful information other than CRUDing require extensive programming. Not suited for complex transactions such as banking systems or other highly transactional applications requiring 2-phase commit. SQL cannot be used with NoSQL databases and writing simple queries can be involving. Enough talking, lets take a look at some code. This blog has published multiple blogs on how to access a RDBMS using JPA in a Java EE 6 application. This Tip Of The Day (TOTD) will show you can use MongoDB (a document-oriented database) with a typical 3-tier Java EE 6 application. Lets get started! The complete source code of this project can be downloaded here. Download MongoDB for your platform from here (1.8.2 as of this writing) and start the server as: arun@ArunUbuntu:~/tools/mongodb-linux-x86_64-1.8.2/bin$./mongod./mongod --help for help and startup optionsSun Jun 26 20:41:11 [initandlisten] MongoDB starting : pid=11210port=27017 dbpath=/data/db/ 64-bit Sun Jun 26 20:41:11 [initandlisten] db version v1.8.2, pdfile version4.5Sun Jun 26 20:41:11 [initandlisten] git version:433bbaa14aaba6860da15bd4de8edf600f56501bSun Jun 26 20:41:11 [initandlisten] build sys info: Linuxbs-linux64.10gen.cc 2.6.21.7-2.ec2.v1.2.fc8xen #1 SMP Fri Nov 2017:48:28 EST 2009 x86_64 BOOST_LIB_VERSION=1_41Sun Jun 26 20:41:11 [initandlisten] waiting for connections on port 27017Sun Jun 26 20:41:11 [websvr] web admin interface listening on port 28017 The default directory for the database is /data/db and needs to be created as: sudo mkdir -p /data/db/sudo chown `id -u` /data/db You can specify a different directory using "--dbpath" option. Refer to Quickstart for your specific platform. Using NetBeans, create a Java EE 6 project and make sure to enable CDI and add JavaServer Faces framework. Download MongoDB Java Driver (2.6.3 of this writing) and add it to the project library by selecting "Properties", "LIbraries", "Add Library...", creating a new library by specifying the location of the JAR file, and adding the library to the created project. Edit the generated "index.xhtml" such that it looks like: <h1>Add a new movie</h1><h:form> Name: <h:inputText value="#{movie.name}" size="20"/><br/> Year: <h:inputText value="#{movie.year}" size="6"/><br/> Language: <h:inputText value="#{movie.language}" size="20"/><br/> <h:commandButton actionListener="#{movieSessionBean.createMovie}" action="show" title="Add" value="submit"/></h:form> This page has a simple HTML form with three text boxes and a submit button. The text boxes take name, year, and language of a movie and the submit button invokes the "createMovie" method of "movieSessionBean" and then render "show.xhtml". Create "show.xhtml" ("New" -> "Other..." -> "Other" -> "XHTML File") such that it looks like: <head> <title><h1>List of movies</h1></title> </head> <body> <h:form> <h:dataTable value="#{movieSessionBean.movies}" var="m" > <h:column><f:facet name="header">Name</f:facet>#{m.name}</h:column> <h:column><f:facet name="header">Year</f:facet>#{m.year}</h:column> <h:column><f:facet name="header">Language</f:facet>#{m.language}</h:column> </h:dataTable> </h:form> This page shows the name, year, and language of all movies stored in the database so far. The list of movies is returned by "movieSessionBean.movies" property. Now create the "Movie" class such that it looks like: import com.mongodb.BasicDBObject;import com.mongodb.BasicDBObject;import com.mongodb.DBObject;import javax.enterprise.inject.Model;import javax.validation.constraints.Size;/** * @author arun */@Modelpublic class Movie { @Size(min=1, max=20) private String name; @Size(min=1, max=20) private String language; private int year; // getters and setters for "name", "year", "language" public BasicDBObject toDBObject() { BasicDBObject doc = new BasicDBObject(); doc.put("name", name); doc.put("year", year); doc.put("language", language); return doc; } public static Movie fromDBObject(DBObject doc) { Movie m = new Movie(); m.name = (String)doc.get("name"); m.year = (int)doc.get("year"); m.language = (String)doc.get("language"); return m; } @Override public String toString() { return name + ", " + year + ", " + language; }} Other than the usual boilerplate code, the key methods here are "toDBObject" and "fromDBObject". These methods provide a conversion from "Movie" -> "DBObject" and vice versa. The "DBObject" is a MongoDB class that comes as part of the mongo-2.6.3.jar file and which we added to our project earlier.  The complete javadoc for 2.6.3 can be seen here. Notice, this class also uses Bean Validation constraints and will be honored by the JSF layer. Finally, create "MovieSessionBean" stateless EJB with all the business logic such that it looks like: package org.glassfish.samples;import com.mongodb.BasicDBObject;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.DBObject;import com.mongodb.Mongo;import java.net.UnknownHostException;import java.util.ArrayList;import java.util.List;import javax.annotation.PostConstruct;import javax.ejb.Stateless;import javax.inject.Inject;import javax.inject.Named;/** * @author arun */@Stateless@Namedpublic class MovieSessionBean { @Inject Movie movie; DBCollection movieColl; @PostConstruct private void initDB() throws UnknownHostException { Mongo m = new Mongo(); DB db = m.getDB("movieDB"); movieColl = db.getCollection("movies"); if (movieColl == null) { movieColl = db.createCollection("movies", null); } } public void createMovie() { BasicDBObject doc = movie.toDBObject(); movieColl.insert(doc); } public List<Movie> getMovies() { List<Movie> movies = new ArrayList(); DBCursor cur = movieColl.find(); System.out.println("getMovies: Found " + cur.size() + " movie(s)"); for (DBObject dbo : cur.toArray()) { movies.add(Movie.fromDBObject(dbo)); } return movies; }} The database is initialized in @PostConstruct. Instead of a working with a database table, NoSQL databases work with a schema-less document. The "Movie" class is the document in our case and stored in the collection "movies". The collection allows us to perform query functions on all movies. The "getMovies" method invokes "find" method on the collection which is equivalent to the SQL query "select * from movies" and then returns a List<Movie>. Also notice that there is no "persistence.xml" in the project. Right-click and run the project to see the output as: Enter some values in the text box and click on enter to see the result as: If you reached here then you've successfully used MongoDB in your Java EE 6 application, congratulations! Some food for thought and further play ... SQL to MongoDB mapping shows mapping between traditional SQL -> Mongo query language. Tutorial shows fun things you can do with MongoDB. Try the interactive online shell  The cookbook provides common ways of using MongoDB In terms of this project, here are some tasks that can be tried: Encapsulate database management in a JPA persistence provider. Is it even worth it because the capabilities are going to be very different ? MongoDB uses "BSonObject" class for JSON representation, add @XmlRootElement on a POJO and how a compatible JSON representation can be generated. This will make the fromXXX and toXXX methods redundant.

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  • TOTD #166: Using NoSQL database in your Java EE 6 Applications on GlassFish - MongoDB for now!

    - by arungupta
    The Java EE 6 platform includes Java Persistence API to work with RDBMS. The JPA specification defines a comprehensive API that includes, but not restricted to, how a database table can be mapped to a POJO and vice versa, provides mechanisms how a PersistenceContext can be injected in a @Stateless bean and then be used for performing different operations on the database table and write typesafe queries. There are several well known advantages of RDBMS but the NoSQL movement has gained traction over past couple of years. The NoSQL databases are not intended to be a replacement for the mainstream RDBMS. As Philosophy of NoSQL explains, NoSQL database was designed for casual use where all the features typically provided by an RDBMS are not required. The name "NoSQL" is more of a category of databases that is more known for what it is not rather than what it is. The basic principles of NoSQL database are: No need to have a pre-defined schema and that makes them a schema-less database. Addition of new properties to existing objects is easy and does not require ALTER TABLE. The unstructured data gives flexibility to change the format of data any time without downtime or reduced service levels. Also there are no joins happening on the server because there is no structure and thus no relation between them. Scalability and performance is more important than the entire set of functionality typically provided by an RDBMS. This set of databases provide eventual consistency and/or transactions restricted to single items but more focus on CRUD. Not be restricted to SQL to access the information stored in the backing database. Designed to scale-out (horizontal) instead of scale-up (vertical). This is important knowing that databases, and everything else as well, is moving into the cloud. RBDMS can scale-out using sharding but requires complex management and not for the faint of heart. Unlike RBDMS which require a separate caching tier, most of the NoSQL databases comes with integrated caching. Designed for less management and simpler data models lead to lower administration as well. There are primarily three types of NoSQL databases: Key-Value stores (e.g. Cassandra and Riak) Document databases (MongoDB or CouchDB) Graph databases (Neo4J) You may think NoSQL is panacea but as I mentioned above they are not meant to replace the mainstream databases and here is why: RDBMS have been around for many years, very stable, and functionally rich. This is something CIOs and CTOs can bet their money on without much worry. There is a reason 98% of Fortune 100 companies run Oracle :-) NoSQL is cutting edge, brings excitement to developers, but enterprises are cautious about them. Commercial databases like Oracle are well supported by the backing enterprises in terms of providing support resources on a global scale. There is a full ecosystem built around these commercial databases providing training, performance tuning, architecture guidance, and everything else. NoSQL is fairly new and typically backed by a single company not able to meet the scale of these big enterprises. NoSQL databases are good for CRUDing operations but business intelligence is extremely important for enterprises to stay competitive. RDBMS provide extensive tooling to generate this data but that was not the original intention of NoSQL databases and is lacking in that area. Generating any meaningful information other than CRUDing require extensive programming. Not suited for complex transactions such as banking systems or other highly transactional applications requiring 2-phase commit. SQL cannot be used with NoSQL databases and writing simple queries can be involving. Enough talking, lets take a look at some code. This blog has published multiple blogs on how to access a RDBMS using JPA in a Java EE 6 application. This Tip Of The Day (TOTD) will show you can use MongoDB (a document-oriented database) with a typical 3-tier Java EE 6 application. Lets get started! The complete source code of this project can be downloaded here. Download MongoDB for your platform from here (1.8.2 as of this writing) and start the server as: arun@ArunUbuntu:~/tools/mongodb-linux-x86_64-1.8.2/bin$./mongod./mongod --help for help and startup optionsSun Jun 26 20:41:11 [initandlisten] MongoDB starting : pid=11210port=27017 dbpath=/data/db/ 64-bit Sun Jun 26 20:41:11 [initandlisten] db version v1.8.2, pdfile version4.5Sun Jun 26 20:41:11 [initandlisten] git version:433bbaa14aaba6860da15bd4de8edf600f56501bSun Jun 26 20:41:11 [initandlisten] build sys info: Linuxbs-linux64.10gen.cc 2.6.21.7-2.ec2.v1.2.fc8xen #1 SMP Fri Nov 2017:48:28 EST 2009 x86_64 BOOST_LIB_VERSION=1_41Sun Jun 26 20:41:11 [initandlisten] waiting for connections on port 27017Sun Jun 26 20:41:11 [websvr] web admin interface listening on port 28017 The default directory for the database is /data/db and needs to be created as: sudo mkdir -p /data/db/sudo chown `id -u` /data/db You can specify a different directory using "--dbpath" option. Refer to Quickstart for your specific platform. Using NetBeans, create a Java EE 6 project and make sure to enable CDI and add JavaServer Faces framework. Download MongoDB Java Driver (2.6.3 of this writing) and add it to the project library by selecting "Properties", "LIbraries", "Add Library...", creating a new library by specifying the location of the JAR file, and adding the library to the created project. Edit the generated "index.xhtml" such that it looks like: <h1>Add a new movie</h1><h:form> Name: <h:inputText value="#{movie.name}" size="20"/><br/> Year: <h:inputText value="#{movie.year}" size="6"/><br/> Language: <h:inputText value="#{movie.language}" size="20"/><br/> <h:commandButton actionListener="#{movieSessionBean.createMovie}" action="show" title="Add" value="submit"/></h:form> This page has a simple HTML form with three text boxes and a submit button. The text boxes take name, year, and language of a movie and the submit button invokes the "createMovie" method of "movieSessionBean" and then render "show.xhtml". Create "show.xhtml" ("New" -> "Other..." -> "Other" -> "XHTML File") such that it looks like: <head> <title><h1>List of movies</h1></title> </head> <body> <h:form> <h:dataTable value="#{movieSessionBean.movies}" var="m" > <h:column><f:facet name="header">Name</f:facet>#{m.name}</h:column> <h:column><f:facet name="header">Year</f:facet>#{m.year}</h:column> <h:column><f:facet name="header">Language</f:facet>#{m.language}</h:column> </h:dataTable> </h:form> This page shows the name, year, and language of all movies stored in the database so far. The list of movies is returned by "movieSessionBean.movies" property. Now create the "Movie" class such that it looks like: import com.mongodb.BasicDBObject;import com.mongodb.BasicDBObject;import com.mongodb.DBObject;import javax.enterprise.inject.Model;import javax.validation.constraints.Size;/** * @author arun */@Modelpublic class Movie { @Size(min=1, max=20) private String name; @Size(min=1, max=20) private String language; private int year; // getters and setters for "name", "year", "language" public BasicDBObject toDBObject() { BasicDBObject doc = new BasicDBObject(); doc.put("name", name); doc.put("year", year); doc.put("language", language); return doc; } public static Movie fromDBObject(DBObject doc) { Movie m = new Movie(); m.name = (String)doc.get("name"); m.year = (int)doc.get("year"); m.language = (String)doc.get("language"); return m; } @Override public String toString() { return name + ", " + year + ", " + language; }} Other than the usual boilerplate code, the key methods here are "toDBObject" and "fromDBObject". These methods provide a conversion from "Movie" -> "DBObject" and vice versa. The "DBObject" is a MongoDB class that comes as part of the mongo-2.6.3.jar file and which we added to our project earlier.  The complete javadoc for 2.6.3 can be seen here. Notice, this class also uses Bean Validation constraints and will be honored by the JSF layer. Finally, create "MovieSessionBean" stateless EJB with all the business logic such that it looks like: package org.glassfish.samples;import com.mongodb.BasicDBObject;import com.mongodb.DB;import com.mongodb.DBCollection;import com.mongodb.DBCursor;import com.mongodb.DBObject;import com.mongodb.Mongo;import java.net.UnknownHostException;import java.util.ArrayList;import java.util.List;import javax.annotation.PostConstruct;import javax.ejb.Stateless;import javax.inject.Inject;import javax.inject.Named;/** * @author arun */@Stateless@Namedpublic class MovieSessionBean { @Inject Movie movie; DBCollection movieColl; @PostConstruct private void initDB() throws UnknownHostException { Mongo m = new Mongo(); DB db = m.getDB("movieDB"); movieColl = db.getCollection("movies"); if (movieColl == null) { movieColl = db.createCollection("movies", null); } } public void createMovie() { BasicDBObject doc = movie.toDBObject(); movieColl.insert(doc); } public List<Movie> getMovies() { List<Movie> movies = new ArrayList(); DBCursor cur = movieColl.find(); System.out.println("getMovies: Found " + cur.size() + " movie(s)"); for (DBObject dbo : cur.toArray()) { movies.add(Movie.fromDBObject(dbo)); } return movies; }} The database is initialized in @PostConstruct. Instead of a working with a database table, NoSQL databases work with a schema-less document. The "Movie" class is the document in our case and stored in the collection "movies". The collection allows us to perform query functions on all movies. The "getMovies" method invokes "find" method on the collection which is equivalent to the SQL query "select * from movies" and then returns a List<Movie>. Also notice that there is no "persistence.xml" in the project. Right-click and run the project to see the output as: Enter some values in the text box and click on enter to see the result as: If you reached here then you've successfully used MongoDB in your Java EE 6 application, congratulations! Some food for thought and further play ... SQL to MongoDB mapping shows mapping between traditional SQL -> Mongo query language. Tutorial shows fun things you can do with MongoDB. Try the interactive online shell  The cookbook provides common ways of using MongoDB In terms of this project, here are some tasks that can be tried: Encapsulate database management in a JPA persistence provider. Is it even worth it because the capabilities are going to be very different ? MongoDB uses "BSonObject" class for JSON representation, add @XmlRootElement on a POJO and how a compatible JSON representation can be generated. This will make the fromXXX and toXXX methods redundant.

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  • Using wildcard SSL certs (chain certificate) with mod_gnutls

    - by QWade
    I have a wildcard SSL certificate from GoDaddy that has three files: wildcard.crt gd_bundle.crt wildcard.key In setting up mod_gnutls to be used with Apache, I can get the site to come up, but it throws a warning that the SSL certificate has not been validated by a CA. When I use mod_ssl, I can stipulate a SSLCertificateChainFile directive and point it at the bd_bundle.crt file. I do not see how to do this with mod_gnutls. Any help is appreciated. I also know that mod_ssl supports SNI, so if there is not an easy answer, I will just try that. Thanks, QWade

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  • How to Configure Windows Machine to Allow File Sharing with DNS Alias

    - by Michael Ferrante
    I have not seen a single article posted anywhere online that brings together all the settings one would need to do to make this work properly on Windows, so I thought I would post it here. To facilitate failover schemes, a common technique is to use DNS CNAME records (DNS Aliases) for different machine roles. Then instead of changing the Windows computername of the actual machine name, one can switch a DNS record to point to a new host. This can work on Microsoft Windows machines, but to make it work with file sharing the following configuration steps need to be taken. Outline The Problem The Solution Allowing other machines to use filesharing via the DNS Alias (DisableStrictNameChecking) Allowing server machine to use filesharing with itself via the DNS Alias (BackConnectionHostNames) Providing browse capabilities for multiple NetBIOS names (OptionalNames) Register the Kerberos service principal names (SPNs) for other Windows functions like Printing (setspn) References 1. The Problem On Windows machines, file sharing can work via the computer name, with or without full qualification, or by the IP Address. By default, however, filesharing will not work with arbitrary DNS aliases. To enable filesharing and other Windows services to work with DNS aliases, you must make registry changes as detailed below and reboot the machine. 2. The Solution Allowing other machines to use filesharing via the DNS Alias (DisableStrictNameChecking) This change alone will allow other machines on the network to connect to the machine using any arbitrary hostname. (However this change will not allow a machine to connect to itself via a hostname, see BackConnectionHostNames below). Edit the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters and add a value DisableStrictNameChecking of type DWORD set to 1. Allowing server machine to use filesharing with itself via the DNS Alias (BackConnectionHostNames) This change is necessary for a DNS alias to work with filesharing from a machine to find itself. This creates the Local Security Authority host names that can be referenced in an NTLM authentication request. To do this, follow these steps for all the nodes on the client computer: To the registry subkey HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0, add new Multi-String Value BackConnectionHostNames In the Value data box, type the CNAME or the DNS alias, that is used for the local shares on the computer, and then click OK. Note: Type each host name on a separate line. Providing browse capabilities for multiple NetBIOS names (OptionalNames) Allows ability to see the network alias in the network browse list. Edit the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\parameters and add a value OptionalNames of type Multi-String Add in a newline delimited list of names that should be registered under the NetBIOS browse entries Names should match NetBIOS conventions (i.e. not FQDN, just hostname) Register the Kerberos service principal names (SPNs) for other Windows functions like Printing (setspn) NOTE: Should not need to do this for basic functions to work, documented here for completeness. We had one situation in which the DNS alias was not working because there was an old SPN record interfering, so if other steps aren't working check if there are any stray SPN records. You must register the Kerberos service principal names (SPNs), the host name, and the fully-qualified domain name (FQDN) for all the new DNS alias (CNAME) records. If you do not do this, a Kerberos ticket request for a DNS alias (CNAME) record may fail and return the error code KDC_ERR_S_SPRINCIPAL_UNKNOWN. To view the Kerberos SPNs for the new DNS alias records, use the Setspn command-line tool (setspn.exe). The Setspn tool is included in Windows Server 2003 Support Tools. You can install Windows Server 2003 Support Tools from the Support\Tools folder of the Windows Server 2003 startup disk. How to use the tool to list all records for a computername: setspn -L computername To register the SPN for the DNS alias (CNAME) records, use the Setspn tool with the following syntax: setspn -A host/your_ALIAS_name computername setspn -A host/your_ALIAS_name.company.com computername 3. References All the Microsoft references work via: http://support.microsoft.com/kb/ Connecting to SMB share on a Windows 2000-based computer or a Windows Server 2003-based computer may not work with an alias name Covers the basics of making file sharing work properly with DNS alias records from other computers to the server computer. KB281308 Error message when you try to access a server locally by using its FQDN or its CNAME alias after you install Windows Server 2003 Service Pack 1: "Access denied" or "No network provider accepted the given network path" Covers how to make the DNS alias work with file sharing from the file server itself. KB926642 How to consolidate print servers by using DNS alias (CNAME) records in Windows Server 2003 and in Windows 2000 Server Covers more complex scenarios in which records in Active Directory may need to be updated for certain services to work properly and for browsing for such services to work properly, how to register the Kerberos service principal names (SPNs). KB870911 Distributed File System update to support consolidation roots in Windows Server 2003 Covers even more complex scenarios with DFS (discusses OptionalNames). KB829885

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  • Function keys for ASUS n56vm not working

    - by Lars
    i have installed Ubuntu 12.10 (64bits) (3.5.0-18 kernel) on an ASUS N56VM. Most fn+key are working except for: brightness keys (fn+f5/fn+f6) don't work. fn+c - gamma keys fc+v - camera fn+space - toggle speed. I really like, at least, to have the brightness keys working. Can you help? Best Regards $ dmesg | grep -i asus [ 0.000000] DMI: ASUSTeK COMPUTER INC. N56VM/N56VM, BIOS N56VM.206 04/13/2012 [ 0.000000] ACPI: RSDP 00000000cafcc000 00024 (v02 _ASUS_) [ 0.000000] ACPI: XSDT 00000000cafcc078 00074 (v01 _ASUS_ Notebook 01072009 AMI 00010013) [ 0.000000] ACPI: FACP 00000000cafdf858 000F4 (v04 _ASUS_ Notebook 01072009 AMI 00010013) [ 0.000000] ACPI: DSDT 00000000cafcc188 136CA (v02 _ASUS_ Notebook 00000013 INTL 20091112) [ 0.000000] ACPI: APIC 00000000cafdf950 00092 (v03 _ASUS_ Notebook 01072009 AMI 00010013) [ 0.000000] ACPI: FPDT 00000000cafdf9e8 00044 (v01 _ASUS_ Notebook 01072009 AMI 00010013) [ 0.000000] ACPI: ECDT 00000000cafdfa30 000C1 (v01 _ASUS_ Notebook 01072009 AMI. 00000005) [ 0.000000] ACPI: MCFG 00000000cafdfaf8 0003C (v01 _ASUS_ Notebook 01072009 MSFT 00000097) [ 0.000000] ACPI: SLIC 00000000cafdfb38 00176 (v01 _ASUS_ Notebook 01072009 ASUS 00000001) [ 0.000000] ACPI: HPET 00000000cafdfcb0 00038 (v01 _ASUS_ Notebook 01072009 AMI. 00000005) [ 0.000000] ACPI: BGRT 00000000cafe1090 00038 (v00 _ASUS_ Notebook 01072009 ASUS 00010013) [ 9.670500] asus_wmi: ASUS WMI generic driver loaded [ 9.671627] asus_wmi: Initialization: 0x1asus_wmi: BIOS WMI version: 7.9 [ 9.671673] asus_wmi: SFUN value: 0x6a0877<6>[ 9.672086] input: Asus WMI hotkeys as /devices/platform/asus-nb-wmi/input/input4 [ 9.732438] Registered led device: asus::kbd_backlight [ 9.733242] asus_wmi: Backlight controlled by ACPI video driver

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  • Cloud Based Load Testing Using TF Service &amp; VS 2013

    - by Tarun Arora [Microsoft MVP]
    Originally posted on: http://geekswithblogs.net/TarunArora/archive/2013/06/30/cloud-based-load-testing-using-tf-service-amp-vs-2013.aspx One of the new features announced as part of the Visual Studio 2013 Ultimate Preview is ‘Cloud Based Load Testing’. In this blog post I’ll walk you through, What is Cloud Based Load Testing? How have I been using this feature? – Success story! Where can you find more resources on this feature? What is Cloud Based Load Testing? It goes without saying that performance testing your application not only gives you the confidence that the application will work under heavy levels of stress but also gives you the ability to test how scalable the architecture of your application is. It is important to know how much is too much for your application! Working with various clients in the industry I have realized that the biggest barriers in Load Testing & Performance Testing adoption are, High infrastructure and administration cost that comes with this phase of testing Time taken to procure & set up the test infrastructure Finding use for this infrastructure investment after completion of testing Is cloud the answer? 100% Visual Studio Compatible Scalable and Realistic Start testing in < 2 minutes Intuitive Pay only for what you need Use existing on premise tests on cloud There are a lot of vendors out there offering Cloud Based Load Testing, to name a few, Load Storm Soasta Blaze Meter Blitz And others… The question you may want to ask is, why should you go with Microsoft’s Cloud based Load Test offering. If you are a Microsoft shop or already have investments in Microsoft technologies, you’ll see great benefit in the natural integration this offers with existing Microsoft products such as Visual Studio and Windows Azure. For example, your existing Web tests authored in Visual Studio 2010 or Visual Studio 2012 will run on the cloud without requiring any modifications what so ever. Microsoft’s cloud test rig also supports API based testing, for example, if you are building a WPF application which consumes WCF services, you can write unit tests to invoke the WCF service, these tests can be run on the cloud test rig and loaded with ‘N’ concurrent users for performance testing. If you have your assets already hosted in the Azure and possibly in the same data centre as the Cloud test rig, your Azure app will not incur a usage cost because of the generated traffic since the traffic is coming from the same data centre. The licensing or pricing information on Microsoft’s cloud based Load test service is yet to be announced, but I would expect this to be priced attractively to match the market competition.   The only additional configuration required for running load tests on Microsoft Cloud based Load Tests service is to select the Test run location as Run tests using Visual Studio Team Foundation Service, How have I been using Microsoft’s Cloud based Load Test Service? I have been part of the Microsoft Cloud Based Load Test Service advisory council for the last 7 months. This gave the opportunity to see the product shape up from concept to working solution. I was also the first person outside of Microsoft to try this offering out. This gave me the opportunity to test real world application at various clients using the Microsoft Load Test Service and provide real world feedback to the Microsoft product team. One of the most recent systems I tested using the Load Test Service has been an insurance quote generation engine. This insurance quote generation engine is,   hosted in Windows Azure expected to get quote requests from across the globe expected to handle 5 Million quote requests in a day (not clear how this load will be distributed across the day) There was no way, I could simulate such kind of load from on premise without standing up additional hardware. But Microsoft’s Cloud based Load Test service allowed me to test my key performance testing scenarios, i.e. Simulate expected Load, Endurance Testing, Threshold Testing and Testing for Latency. Simulating expected load: approach to devising a load pattern My approach to devising a load test pattern has been to run the test scenario with 1 user to figure out the response time. Then work out how many users are required to reach the target load. So, for example, to invoke 1 quote from the quote engine software takes 0.5 seconds. Now if you do the math,   1 quote request by 1 user = 0.5 seconds   quotes generated by 1 user in 24 hour = 1 * (((2 * 60) * 60) * 24) = 172,800   quotes generated by 30 users in 24 hours = 172,800 * 30 =  5,184,000 This was a very simple example, if your application requires more concurrent users to test scenario’s such as caching, etc then you can devise your own load pattern, some examples of load test patterns can be found here.  Endurance Testing To test for endurance, I loaded the quote generation engine with an expected fixed user load and ran the test for very long duration such as over 48 hours and observed the affect of the long running test on the Azure infrastructure. Currently Microsoft Load Test service does not support metrics from the machine under test. I used Azure diagnostics to begin with, but later started using Cerebrata Azure Diagnostics Manager to capture the metrics of the machine under test. Threshold Testing To figure out how much user load the application could cope with before falling on its belly, I opted to step load the quote generation engine by incrementing user load with different variations of incremental user load per minute till the application crashed out and forced an IIS reset. Testing for Latency Currently the Microsoft Load Test service does not support generating geographically distributed load, I however, deployed the insurance quote generation engine in different Azure data centres and ran the same set of performance tests to measure for latency. Because I could compare load test results from different runs by exporting the results to excel (this feature is provided out of the box right from Visual Studio 2010) I could see the different in response times. More resources on Microsoft Cloud based Load Test Service A few important links to get you started, Download Visual Studio Ultimate 2013 Preview Getting started guide for load testing using Team Foundation Service Troubleshooting guide for FAQs and known issues Team Foundation Service forum for questions and support Detailed demo and presentation (link to Tech-Ed session recording) Detailed demo and presentation (link to Build session recording) There a few limits on the usage of Microsoft Cloud based Load Test service that you can read about here. If you have any feedback on Microsoft Cloud based Load Test service, feel free to share it with the product team via the Visual Studio User Voice forum. I hope you found this useful. Thank you for taking the time out and reading this blog post. If you enjoyed the post, remember to subscribe to http://feeds.feedburner.com/TarunArora. Stay tuned!

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  • Auto-Suggest via &lsquo;Trie&rsquo; (Pre-fix Tree)

    - by Strenium
    Auto-Suggest (Auto-Complete) “thing” has been around for a few years. Here’s my little snippet on the subject. For one of my projects, I had to deal with a non-trivial set of items to be pulled via auto-suggest used by multiple concurrent users. Simple, dumb iteration through a list in local cache or back-end access didn’t quite cut it. Enter a nifty little structure, perfectly suited for storing and matching verbal data: “Trie” (http://tinyurl.com/db56g) also known as a Pre-fix Tree: “Unlike a binary search tree, no node in the tree stores the key associated with that node; instead, its position in the tree defines the key with which it is associated. All the descendants of a node have a common prefix of the string associated with that node, and the root is associated with the empty string. Values are normally not associated with every node, only with leaves and some inner nodes that correspond to keys of interest.” This is a very scalable, performing structure. Though, as usual, something ‘fast’ comes at a cost of ‘size’; fortunately RAM is more plentiful today so I can live with that. I won’t bore you with the detailed algorithmic performance here - Google can do a better job of such. So, here’s C# implementation of all this. Let’s start with individual node: Trie Node /// <summary> /// Contains datum of a single trie node. /// </summary> public class AutoSuggestTrieNode {     public char Value { get; set; }       /// <summary>     /// Gets a value indicating whether this instance is leaf node.     /// </summary>     /// <value>     ///     <c>true</c> if this instance is leaf node; otherwise, a prefix node <c>false</c>.     /// </value>     public bool IsLeafNode { get; private set; }       public List<AutoSuggestTrieNode> DescendantNodes { get; private set; }         /// <summary>     /// Initializes a new instance of the <see cref="AutoSuggestTrieNode"/> class.     /// </summary>     /// <param name="value">The phonetic value.</param>     /// <param name="isLeafNode">if set to <c>true</c> [is leaf node].</param>     public AutoSuggestTrieNode(char value = ' ', bool isLeafNode = false)     {         Value = value;         IsLeafNode = isLeafNode;           DescendantNodes = new List<AutoSuggestTrieNode>();     }       /// <summary>     /// Gets the descendants of the pre-fix node, if any.     /// </summary>     /// <param name="descendantValue">The descendant value.</param>     /// <returns></returns>     public AutoSuggestTrieNode GetDescendant(char descendantValue)     {         return DescendantNodes.FirstOrDefault(descendant => descendant.Value == descendantValue);     } }   Quite self-explanatory, imho. A node is either a “Pre-fix” or a “Leaf” node. “Leaf” contains the full “word”, while the “Pre-fix” nodes act as indices used for matching the results.   Ok, now the Trie: Trie Structure /// <summary> /// Contains structure and functionality of an AutoSuggest Trie (Pre-fix Tree) /// </summary> public class AutoSuggestTrie {     private readonly AutoSuggestTrieNode _root = new AutoSuggestTrieNode();       /// <summary>     /// Adds the word to the trie by breaking it up to pre-fix nodes + leaf node.     /// </summary>     /// <param name="word">Phonetic value.</param>     public void AddWord(string word)     {         var currentNode = _root;         word = word.Trim().ToLower();           for (int i = 0; i < word.Length; i++)         {             var child = currentNode.GetDescendant(word[i]);               if (child == null) /* this character hasn't yet been indexed in the trie */             {                 var newNode = new AutoSuggestTrieNode(word[i], word.Count() - 1 == i);                   currentNode.DescendantNodes.Add(newNode);                 currentNode = newNode;             }             else                 currentNode = child; /* this character is already indexed, move down the trie */         }     }         /// <summary>     /// Gets the suggested matches.     /// </summary>     /// <param name="word">The phonetic search value.</param>     /// <returns></returns>     public List<string> GetSuggestedMatches(string word)     {         var currentNode = _root;         word = word.Trim().ToLower();           var indexedNodesValues = new StringBuilder();         var resultBag = new ConcurrentBag<string>();           for (int i = 0; i < word.Trim().Length; i++)  /* traverse the trie collecting closest indexed parent (parent can't be leaf, obviously) */         {             var child = currentNode.GetDescendant(word[i]);               if (child == null || word.Count() - 1 == i)                 break; /* done looking, the rest of the characters aren't indexed in the trie */               indexedNodesValues.Append(word[i]);             currentNode = child;         }           Action<AutoSuggestTrieNode, string> collectAllMatches = null;         collectAllMatches = (node, aggregatedValue) => /* traverse the trie collecting matching leafNodes (i.e. "full words") */             {                 if (node.IsLeafNode) /* full word */                     resultBag.Add(aggregatedValue); /* thread-safe write */                   Parallel.ForEach(node.DescendantNodes, descendandNode => /* asynchronous recursive traversal */                 {                     collectAllMatches(descendandNode, String.Format("{0}{1}", aggregatedValue, descendandNode.Value));                 });             };           collectAllMatches(currentNode, indexedNodesValues.ToString());           return resultBag.OrderBy(o => o).ToList();     }         /// <summary>     /// Gets the total words (leafs) in the trie. Recursive traversal.     /// </summary>     public int TotalWords     {         get         {             int runningCount = 0;               Action<AutoSuggestTrieNode> traverseAllDecendants = null;             traverseAllDecendants = n => { runningCount += n.DescendantNodes.Count(o => o.IsLeafNode); n.DescendantNodes.ForEach(traverseAllDecendants); };             traverseAllDecendants(this._root);               return runningCount;         }     } }   Matching operations and Inserts involve traversing the nodes before the right “spot” is found. Inserts need be synchronous since ordering of data matters here. However, matching can be done in parallel traversal using recursion (line 64). Here’s sample usage:   [TestMethod] public void AutoSuggestTest() {     var autoSuggestCache = new AutoSuggestTrie();       var testInput = @"Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer nec odio. Praesent libero.                 Sed cursus ante dapibus diam. Sed nisi. Nulla quis sem at nibh elementum imperdiet. Duis sagittis ipsum. Praesent mauris.                 Fusce nec tellus sed augue semper porta. Mauris massa. Vestibulum lacinia arcu eget nulla. Class aptent taciti sociosqu ad                 litora torquent per conubia nostra, per inceptos himenaeos. Curabitur sodales ligula in libero. Sed dignissim lacinia nunc.                 Curabitur tortor. Pellentesque nibh. Aenean quam. In scelerisque sem at dolor. Maecenas mattis. Sed convallis tristique sem.                 Proin ut ligula vel nunc egestas porttitor. Morbi lectus risus, iaculis vel, suscipit quis, luctus non, massa. Fusce ac                 turpis quis ligula lacinia aliquet. Mauris ipsum. Nulla metus metus, ullamcorper vel, tincidunt sed, euismod in, nibh. Quisque                 volutpat condimentum velit. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Nam                 nec ante. Sed lacinia, urna non tincidunt mattis, tortor neque adipiscing diam, a cursus ipsum ante quis turpis. Nulla                 facilisi. Ut fringilla. Suspendisse potenti. Nunc feugiat mi a tellus consequat imperdiet. Vestibulum sapien. Proin quam. Etiam                 ultrices. Suspendisse in justo eu magna luctus suscipit. Sed lectus. Integer euismod lacus luctus magna. Quisque cursus, metus                 vitae pharetra auctor, sem massa mattis sem, at interdum magna augue eget diam. Vestibulum ante ipsum primis in faucibus orci                 luctus et ultrices posuere cubilia Curae; Morbi lacinia molestie dui. Praesent blandit dolor. Sed non quam. In vel mi sit amet                 augue congue elementum. Morbi in ipsum sit amet pede facilisis laoreet. Donec lacus nunc, viverra nec.";       testInput.Split(' ').ToList().ForEach(word => autoSuggestCache.AddWord(word));       var testMatches = autoSuggestCache.GetSuggestedMatches("le"); }   ..and the result: That’s it!

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  • Stupid Geek Tricks: Compare Your Browser’s Memory Usage with Google Chrome

    - by The Geek
    Ever tried to figure out exactly how much memory Google Chrome or Internet Explorer is using? Since they each show up a bunch of times in Task Manager, it’s not so easy! Here’s the quick and easy way to compare them. Both Chrome and IE use multiple processes to isolate tabs from each other, to make sure that one tab doesn’t kill the whole browser. Firefox, on the other hand, just uses a single process for everything. Rather than pulling out a calculator and adding them all up, you can just open up Google Chrome, and type in about:memory into the location bar to see a full list of each browser’s memory usage.   On my test system with 6 GB of system RAM, I’m running the Development channel version of Chrome, and I’ve got about 40 different tabs open, which is why the memory usage is so high. Firefox has 8 tabs open, and IE is enjoying being opened for the first time in forever. Want to help cut down on memory usage and keep your Chrome browser running fast? Disable all unnecessary extensions, and then make sure you disable any plug-ins that you don’t need either. Similar Articles Productive Geek Tips Stupid Geek Tricks: Duplicate a Tab with a Shortcut Key in Chrome or FirefoxStupid Geek Tricks: Shrink the XP Volume ControlStupid Geek Tricks: Tile or Cascade Multiple Windows in Windows 7Fix for Firefox memory leak on WindowsHow to Purge Memory in Google Chrome TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Free MP3s from Amazon Awe inspiring, inter-galactic theme (Win 7) Case Study – How to Optimize Popular Wordpress Sites Restore Hidden Updates in Windows 7 & Vista Iceland an Insurance Job? Find Downloads and Add-ins for Outlook

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  • Suggested Web Application Framework and Database for Enterprise, “Big-Data” App?

    - by willOEM
    I have a web application that I have been developing for a small group within my company over the past few years, using Pipeline Pilot (plus jQuery and Python scripting) for web development and back-end computation, and Oracle 10g for my RDBMS. Users upload experimental genomic data, which is parsed into a database, and made available for querying, transformation, and reporting. Experimental data sets are large and have many layers of metadata. A given experimental data record might have a foreign key relationship with a table that describes this data point's assay. Assays can cover multiple genes, which can have multiple transcript, which can have multiple mutations, which can affect multiple signaling pathways, etc. Users need to approach this data from any point in those layers in the metadata. Since all data sets for a given data type can run over a billion rows, this results in some large, dynamic queries that are hard to predict. New data sets are added on a weekly basis (~1GB per set). Experimental data is never updated, but the associated metadata can be updated weekly for a few records and yearly for most others. For every data set insert the system sees, there will be between 10 and 100 selects run against it and associated data. It is okay for updates and inserts to run slow, so long as queries run quick and are as up-to-date as possible. The application continues to grow in size and scope and is already starting to run slower than I like. I am worried that we have about outgrown Pipeline Pilot, and perhaps Oracle (as the sole database). Would a NoSQL database or an OLAP system be appropriate here? What web application frameworks work well with systems like this? I'd like the solution to be something scalable, portable and supportable X-years down the road. Here is the current state of the application: Web Server/Data Processing: Pipeline Pilot on Windows Server + IIS Database: Oracle 10g, ~1TB of data, ~180 tables with several billion-plus row tables Network Storage: Isilon, ~50TB of low-priority raw data

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  • Windows 8.1 Enterprise Sysprep Error

    - by Anurag Shetti
    I am Trying to sysprep my WIndows 8.1 enterprise (MSDN) and i get the following errors I have upgraded the Windows 8 to windows 8.1 and the machine contains all the configuration for VS 2012 and rest Exact error Sysprep was not able to validate your windows installation Error msg line in log C:\Users\André>err 0x8007139f # as an HRESULT: Severity: FAILURE (1), FACILITY_WIN32 (0x7), Code 0x139f # for hex 0x139f / decimal 5023 ERROR_INVALID_STATE winerror.h # The group or resource is not in the correct state to # perform the requested operation. # 1 matches found for "0x8007139f" SYSPRP ActionPlatform::GetValue: Error from RegQueryValueEx on value SysprepMode under key HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Setup\Sysprep; dwRet = 0x2 I have searched the HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Setup\Sysprep But i coud'nt find anything for SYSprep mode The value for sysprep was (Value not set)

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  • What&rsquo;s wrong with See[Mike]Code? (no relation)

    - by mbcrump
    I have been hearing a lot about the website See[Mike]Code. Basically, the site creates an interview url and a job candidate url and lets you see the potential programmer’s code (specifically .NET developer). Below is the candidate’s URL   Below is the interviewer url   So you might think, ah, this is a good thing. We can screen candidates cheaper and more efficiently. In reality, this is only a good thing if you want your programmer to develop using notepad.  I use the most efficient tools that exist to do my job. I would simply fire up VS2010 and type “for” and hit the tab key twice and get the following template.   I have no problem keeping MSDN/Google in one of my monitors. I spend time learning VS macros and using Aurora XAML/Expression to produce my XAML for WPF. Sure, I can write a for loop without using the VS Macro, but the real question is, “Why should I?”. My point being, if you really want to test a .NET programmer knowledge then fire up his native working environment and let him use the features of the IDE to develop the simple 10-line program. For a more sophisticated program, then give him 20 minutes and allow access to msdn/google. If the programmer cannot find at the right path then give him the boot.

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  • Setting up SSL virtual hosts in Apache

    - by Bart van Heukelom
    I'm trying to set up SSL, with SNI, in my apache and am getting the often-seen "ssl_error_rx_record_too_long" error in Firefox when accessing the site (https://test.me.dev.xxxx.net), from which I can conclude that the server is listening on port 443, but doesn't know to use SSL on it. The server is Ubuntu 9.04 with Apache 2.2.11 I enabled SSL in the default way (a2enmod ssl). Here is my relevant config: NameVirtualHost *:* Listen 80 <IfModule mod_ssl.c> Listen 443 </IfModule> ... <VirtualHost *:*> DocumentRoot /home ServerAlias *.dev.xxxx.net UseCanonicalName Off # project.user.dev.xxxx.net VirtualDocumentRoot /home/%2/dev/%1/web SSLEngine On SSLCertificateFile /etc/apache2/certs/dev.crt SSLCertificateKeyFile /etc/apache2/certs/dev.key </VirtualHost> What is wrong?

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  • Run WordPress & Other Web Apps with Windows Web Platform

    - by Matthew Guay
    Would you like to run WordPress or other web apps on your PC so you can easily test and design websites?  Here we’ll look at how you can get the latest web apps on your computer in only a few quick steps. Many web apps today, such as WordPress, MediaWiki, and more, are open source and can be run for free from any computer with even a simple local web server.  They are often very difficult to install on your computer, since they require a number of dependencies such as PHP and MySQL.  Microsoft has worked to make this easier, releasing the Windows Web Platform Installer.  This lets you install many popular web apps and free tools in Windows with only a few clicks. Here we’re going to look at how to install WordPress and the free Visual Web Developer 2010 Express to edit web code with the Web Platform Installer.  But, if you’d rather install a different web app or tool, feel free to choose those as the installations are generally similar. Getting Started Head over to Microsoft’s Web development site and download the Web Platform Installer (link below).  This will download very quick, as it is just a small loader.  When you run this loader, it will download the Web Platform Installer files.  The Web Platform Installer works on XP, Vista, and Windows 7, as well as the related versions of Windows Server. After a couple moments, the Web Platform Installer will open and load information about the latest web offerings.    Now you can choose what you want to install.  You can quickly select the recommended products for several categories such as Web Server, Database, and more. Alternately, click Customize under the category and select exactly what you want to install.  Note that items already installed on your computer will be grayed out. We wanted to install Visual Web Developer 2010 Express, so select Customize under Tools, and select Visual Web Developer 2010 Express. Or, for more preset choices, select Options on the bottom of the window. You can choose to add Multimedia, Developer, and Enterprise tools to the lists, or add a new preset list from a feed. Choose Specific Web apps to Install We wanted to install WordPress, so instead of choosing a preset, select the Web Applications tab on the left.  Now you can choose from a variety of apps based on category, or you can view them all together in an A to Z, Most Popular, or Highest Rating list. Click the checkbox beside the app you want to install to select it, or click the “i” for more information. Here’s the More Information pane for WordPress.  If you’re ready to install it, click the checkbox. Now you can go back and add more web apps or tools to the install list if you like.  The Web Platform Installer will automatically find and select prerequisite apps such as MySQL, so you won’t need to worry about finding them. Once you’ve selected everything you want to install, click the Install button on the bottom of the window. The Web Platform Installer will now show you everything that’s selected, including components that it automatically selected.  Notice we only chose to install WordPress and Visual Web Developer 2010 Express, but it also has selected MySQL and PHP automatically.  Click I Accept to proceed. Enter an administrator password for MySQL before the setup begins. Now the Web Platform Installer will take over, automatically downloading, installing, and configuring all of your web apps.  It will also activate optional Windows components that may be needed on your computer.  This may take several minutes, depending on the components you selected and your internet speed.   Setting up Your Test Site Once the installation is finished, you’ll be asked to enter some information about your site.  You can simply accept the defaults or enter your own choices, and then click Continue. Now you’ll need to enter some information for your web apps.  When installing WordPress, you’ll need to choose a database and enter administrative usernames and passwords.  You may also be asked to enter extra information for additional security, but for a local-only test site this isn’t necessary.  Click Continue when you’re finished. You’ll need to wait a few more moments as it complete the setup of your web apps.  The good thing is, once it’s finished, they’ll be ready to go with only minimal configuration. And you’re finished!  The installer will let you know everything it installed, and if there were any problems.  In our test, Visual Web Developer 2010 Express failed to install successfully.  Often the problems may be with the download, so click Finish and then reselect the apps that didn’t install and run the installer again. Now you’re ready to run WordPress from your PC.  Click the Launch WordPress link or enter http://localhost:80/wordpress in your browser to get started. You’ll only have a little more setup to do on WordPress to get it running.  Once you’ve opened your WordPress page in your browser, enter a name for your blog and your email address, and click Install WordPress.   After a few seconds, you should see a Success! page with your username and a temporary password.  Copy the password, and then click Log In. Enter admin as the Username and paste the random generated password, and click Log In. WordPress will remind you to change the default password.  Click the Yes, Take me to my profile page link to do this. Enter something easier for you to remember, and click Update Profile. Now you’re ready to enjoy your new WordPress install on Windows.  You can add plugins and themes, and everything else you’d do with a normal WordPress site.  Here’s the dashboard running from localhost. And here’s the default blog running. Setting up Visual Web Developer 2010 Express As mentioned before, Visual Web Developer 2010 Express didn’t install correctly on our first try, but the second time it installed seamlessly.  Once it’s installed, launch it from your start menu as normal.  It may take a few minutes to load on the first run as it is finishing up setup. You may notice that the splash screen displayed while the program is loading says For Evaluation Purposes Only.  This is because you still need to register the program. You have 30 days to register the program, but let’s go ahead and do it to get this step out of the way.  Click Help in the menu bar, and select Register Product. Click Obtain a registration key online in the popup window. You’ll need to sign in with your Windows Live ID, and then fill out a quick form. When you’re done, copy the registration key displayed and paste it into the registration dialog in Visual Web Developer.   Now you’ve got a registered, free web development program with full standards compliance and IntelliSense to help you work smarter and faster.  And it works great with your local web apps, so you can create, tweak, and then deploy, all from your desktop with this simple installer! Install More Apps You can always run the Web Platform Installer again in the future and add more apps if you’d like.  The install adds a link to the Installer in the Start menu; just run it and repeat the steps above with your new selections. Also, from the installer, you can cleanup the setup files downloaded during the installation if you want.  Click the Options link in the bottom of the window, and then scroll down and select Delete installer cache folder. Uninstalling the apps is not as easy, unfortunately.  If you wish to uninstall the Web Platform Installer and everything you installed with it, you’ll need to uninstall each item individually.  One easy way to see what was all installed together is to sort the entries in Uninstall Programs by date.  In our case, we also installed some other applications on the same day, but it’s easier to see what was installed together. Or if you are not a fan of using Programs and Features to uninstall them, try out a program like Revo Uninstaller Pro. Conclusion Whether you’re a full-time web developer or just enjoy testing out the latest web apps, the Web Platform Installer makes it quick and easy to get your computer loaded up with the latest bits.  In fact, it’s easier to install these tools with all their dependencies than it is to install many standard boxed programs. If you’d like to take your web server anywhere you go and not have it confined to your desktop, then check out our article on how to Turn Your Flashdrive into a Portable Webserver. Link Download the Microsoft Web Platform Installer Similar Articles Productive Geek Tips Linux QuickTip: Downloading and Un-tarring in One StepQuick Tip: Set a Future Date for a Post in WordPressHow-To Geek SoftwareAdd Social Bookmarking (Digg This!) Links to your Wordpress BlogHow-To Geek Software: WordPress Comment Moderation Notifier TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Snagit 10 Windows Media Player Glass Icons (icons we like) How to Forecast Weather, without Gadgets Outlook Tools, one stop tweaking for any Outlook version Zoofs, find the most popular tweeted YouTube videos Video preview of new Windows Live Essentials 21 Cursor Packs for XP, Vista & 7

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  • Ada and 'The Book'

    - by Phil Factor
    The long friendship between Charles Babbage and Ada Lovelace created one of the most exciting and mysterious of collaborations ever to have resulted in a technological breakthrough. The fireworks that created by the collision of two prodigious mathematical and creative talents resulted in an invention, the Analytical Engine, which went on to change society fundamentally. However, beyond that, we just don't know what the bulk of their collaborative work was about:;  it was done in strictest secrecy. Even the known outcome of their friendship, the first programmable computer, was shrouded in mystery. At the time, nobody, except close friends and family, had any idea of Ada Byron's contribution to the invention of the ‘Engine’, and how to program it. Her great insight was published in August 1843, under the initials AAL, standing for Ada Augusta Lovelace, her title then being the Countess of Lovelace. It was contained in a lengthy ‘note’ to her translation of a publication that remains the best description of Babbage's amazing Analytical Engine. The secret identity of the person behind those enigmatic initials was finally revealed by Prince de Polignac who, seventy years later, wrote to Ada's daughter to seek confirmation that her mother had, indeed, been the author of the brilliant sentences that described so accurately how Babbage's mechanical computer could be programmed with punch-cards. L.F. Menabrea's paper on the Analytical Engine first appeared in the 'Bibliotheque Universelle de Geneve' in October 1842, and Ada translated it anonymously for Taylor's 'Scientific Memoirs'. Charles Babbage was surprised that she had not written an original paper as she already knew a surprising amount about the way the machine worked. He persuaded her to at least write some explanatory notes. These notes ended up extending to four times the length of the original article and represented the first published account of how a machine could be programmed to perform any calculation. Her example of programming the Bernoulli sequence would have worked on the Analytical engine had the device’s construction been completed, and gave Ada an unassailable claim to have invented the art of programming. What was the reason for Ada's secrecy? She was the only legitimate child of Lord Byron, who was probably the best known celebrity of the age, so she was already famous. She was a senior aristocrat, with titles, a fortune in money and vast estates in the Midlands. She had political influence, and was the cousin of Lord Melbourne, who was the Prime Minister at that time. She was friendly with the young Queen Victoria. Her mathematical activities were a pastime, and not one that would be considered by others to be in keeping with her roles and responsibilities. You wouldn't dare to dream up a fictional heroine like Ada. She was dazzlingly beautiful and talented. She could speak several languages fluently, and play some musical instruments with professional skill. Contemporary accounts refer to her being 'accomplished in science, art and literature'. On top of that, she was a brilliant mathematician, a talent inherited from her mother, Annabella Milbanke. In her mother's circle of literary and scientific friends was Charles Babbage, and Ada's friendship with him dates from her teenage zest for Mathematics. She was one of the first people he'd ever met who understood what he had attempted to achieve with the 'Difference Engine', and with whom he could converse as intellectual equals. He arranged for her to have an education from the most talented academics in the country. Ada melted the heart of the cantankerous genius to the point that he became a faithful and loyal father-figure to her. She was one of the very few who could grasp the principles of the later, and very different, ‘Analytical Engine’ which was designed from the start to tackle a variety of tasks. Sadly, Ada Byron's life ended less than a decade after completing the work that assured her long-term fame, in November 1852. She was dying of cancer, her gambling habits had caused her to run up huge debts, she'd had more than one affairs, and she was being blackmailed. Her brilliant but unempathic mother was nursing her in her final illness, destroying her personal letters and records, and repaying her debts. Her husband was distraught but helpless. Charles Babbage, however, maintained his steadfast paternalistic friendship to the end. She appointed her loyal friend to be her executor. For years, she and Babbage had been working together on a secret project, known only as 'The Book'. We have a clue to what it was in a letter written by her nine years earlier, on 11th August 1843. It was a joint project by herself and Lord Lovelace, her husband, and was intended to involve Babbage's 'undivided energies'. It involved 'consulting your Engine' (it required Babbage’s computer). The letter gives no hint about the project except for the high-minded nature of its purpose, and its highly mathematical nature.  From then on, the surviving correspondence between the two gives only veiled references to 'The Book'. There isn't much, since Babbage later destroyed any letters that could have damaged her reputation within the Establishment. 'I cannot spare the book today, which I am very sorry for. At the moment I want it for constant reference, but I think you can have it tomorrow' (Oct 1844)  And 'I will send you the book directly, and you can say, when you receive it, how long you will want to keep it'. (Nov 1844)  The two of them were obviously intent on the work: She writes, four years later, 'I have an engagement for Wednesday which will prevent me from attending to your wishes about the book' (Dec 1848). This was something that they both needed to work on, but could not do in parallel: 'I will send the book on Tuesday, and it can be left with you till Friday' (11 Feb 1849). After six years work, it had been so well-handled that it was beginning to fall apart: 'Don't forget the new cover you promised for the book. The poor book is very shabby and wants one' (20 Sept 1849). So what was going on? The word 'book' was not a code-word: it was a real book, probably a 'printer's blank', plain paper, but properly bound so printers and publishers could show off how the published work might look. The hints from the correspondence are of advanced mathematics. It is obvious that the book was travelling between them, back and forth, each one working on it for less than a week before passing it back. Ada and her husband were certainly involved in gambling large sums of money on the horses, and so most biographers have concluded that the three of them were trying to calculate the mathematical odds on the horses. This theory has three large problems. Firstly, Ada's original letter proposing the project refers to its high-minded nature. Babbage was temperamentally opposed to gambling and would scarcely have given so much time to the project, even though he was devoted to Ada. Secondly, Babbage would have very soon have realized the hopelessness of trying to beat the bookies. This sort of betting never attracts his type of intellectual background. The third problem is that any work on calculating the odds on horses would not need a well-thumbed book to pass back and forth between them; they would have not had to work in series. The original project was instigated by Ada, along with her husband, William King-Noel, 1st Earl of Lovelace. Charles Babbage was invited to join the project after the couple had come up with the idea. What could William have contributed? One might assume that William was a Bertie Wooster character, addicted only to the joys of the turf, but this was far from the truth. He was a scientist, a Cambridge graduate who was later elected to be a Fellow of the Royal Society. After Eton, he went to Trinity College, Cambridge. On graduation, he entered the diplomatic service and acted as secretary under Lord Nugent, who was Lord Commissioner of the Ionian Islands. William was very friendly with Babbage too, able to discuss scientific matters on equal terms. He was a capable engineer who invented a process for bending large timbers by the application of steam heat. He delivered a paper to the Institution of Civil Engineers in 1849, and received praise from the great engineer, Isambard Kingdom Brunel. As well as being Lord Lieutenant of the County of Surrey for most of Victoria's reign, he had time for a string of scientific and engineering achievements. Whatever the project was, it is unlikely that William was a junior partner. After Ada's death, the project disappeared. Then, two years later, Babbage, through one of his occasional outbursts of temper, demonstrated that he was able to decrypt one of the most powerful of secret codes, Vigenère's autokey cipher.  All contemporary diplomatic and military messages used a variant of this cipher. Babbage had made three important discoveries, namely, the mathematical law of this cipher, the principle of the key periodicity, and the technique of the symmetry of position. The technique is now known as the Kasiski examination, also called the Kasiski test, but Babbage got there first. At one time, he listed amongst his future projects, the writing of a book 'The Philosophy of Decyphering', but it never came to anything. This discovery was going to change the course of history, since it was used to decipher the Russians’ military dispatches in the Crimean war. Babbage himself played a role during the Crimean War as a cryptographical adviser to his friend, Rear-Admiral Sir Francis Beaufort of the Admiralty. This is as much as we can be certain about in trying to make sense of the bulk of the time that Charles Babbage and Ada Lovelace worked together. Nine years of intensive work, involving the 'Engine' and a great deal of mathematics and research seems to have been lost: or has it? I've argued in the past http://www.simple-talk.com/community/blogs/philfactor/archive/2008/06/13/59614.aspx that the cracking of the Vigenère autokey cipher, was a fundamental motive behind the British Government's support and funding of the 'Difference Engine'. The Duke of Wellington, whose understanding of the military significance of being able to read enemy dispatches, was the most steadfast advocate of the project. If the three friends were actually doing the work of cracking codes by mathematical techniques that used the techniques of key periodicity, and symmetry of position (the use of a book being passed quickly to and fro is very suggestive), intending to then use the 'Engine' to do the routine cracking of each dispatch, then this is a rather different story. The project was Ada and William's idea. (William had served in the diplomatic service and would be familiar with the use of codes). This makes Ada Lovelace the initiator of a project which, by giving both Britain, and probably the USA, a diplomatic and military advantage in the second part of the Nineteenth century, changed world history. Ada would never have wanted any credit for cracking the cipher, and developing the method that rendered all contemporary military and diplomatic ciphering techniques nugatory; quite the reverse. And it is clear from the gaps in the record of the letters between the collaborators that the evidence was destroyed, probably on her request by her irascible but intensely honorable executor, Charles Babbage. Charles Babbage toyed with the idea of going public, but the Crimean war put an end to that. The British Government had a valuable secret, and intended to keep it that way. Ada and Charles had quite often discussed possible moneymaking projects that would fund the development of the Analytic Engine, the first programmable computer, but their secret work was never in the running as a potential cash cow. I suspect that the British Government was, even then, working on the concealment of a discovery whose value to the nation depended on it remaining so. The success of code-breaking in the Crimean war, and the American Civil war, led to the British and Americans  subsequently giving much more weight and funding to the science of decryption. Paradoxically, this makes Ada's contribution even closer to the creation of Colossus, the first digital computer, at Bletchley Park, specifically to crack the Nazi’s secret codes.

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  • 202 blog articles

    - by mprove
    All my blog articles under blogs.oracle.com since August 2005: 202 blog articles Apr 2012 blogs.oracle.com design patch Mar 2012 Interaction 12 - Critique Mar 2012 Typing. Clicking. Dancing. Feb 2012 Desktop Mobility in Hospitals with Oracle VDI /video Feb 2012 Interaction 12 in Dublin - Highlights of Day 3 Feb 2012 Interaction 12 in Dublin - Highlights of Day 2 Feb 2012 Interaction 12 in Dublin - Highlights of Day 1 Feb 2012 Shit Interaction Designers Say Feb 2012 Tips'n'Tricks for WebCenter #3: How to display custom page titles in Spaces Jan 2012 Tips'n'Tricks for WebCenter #2: How to create an Admin menu in Spaces and save a lot of time Jan 2012 Tips'n'Tricks for WebCenter #1: How to apply custom resources in Spaces Jan 2012 Merry XMas and a Happy 2012! Dec 2011 One Year Oracle SocialChat - The Movie Nov 2011 Frank Ludolph's Last Working Day Nov 2011 Hans Rosling at TED Oct 2011 200 Countries x 200 Years Oct 2011 Blog Aggregation for Desktop Virtualization Oct 2011 Oracle VDI at OOW 2011 Sep 2011 Design for Conversations & Conversations for Design Sep 2011 All Oracle UX Blogs Aug 2011 Farewell Loriot Aug 2011 Oracle VDI 3.3 Overview Aug 2011 Sutherland's Closing Remarks at HyperKult Aug 2011 Surface and Subface Aug 2011 Back to Childhood in UI Design Jul 2011 The Art of Engineering and The Engineering of Art Jul 2011 Oracle VDI Seminar - June-30 Jun 2011 SGD White Paper May 2011 TEDxHamburg Live Feed May 2011 Oracle VDI in 3 Minutes May 2011 Space Ship Earth 2011 May 2011 blog moving times Apr 2011 Frozen tag cloud Apr 2011 Oracle: Hardware Software Complete in 1953 Apr 2011 Interaction Design with Wireframes Apr 2011 A guide to closing down a project Feb 2011 Oracle VDI 3.2.2 Jan 2011 free VDI charts Jan 2011 Sun Founders Panel 2006 Dec 2010 Sutherland on Leadership Dec 2010 SocialChat: Efficiency of E20 Dec 2010 ALWAYS ON Desktop Virtualization Nov 2010 12,000 Desktops at JavaOne Nov 2010 SocialChat on Sharing Best Practices Oct 2010 Globe of Visitors Oct 2010 SocialChat about the Next Big Thing Oct 2010 Oracle VDI UX Story - Wireframes Oct 2010 What's a PC anyway? Oct 2010 SocialChat on Getting Things Done Oct 2010 SocialChat on Infoglut Oct 2010 IT Twenty Twenty Oct 2010 Desktop Virtualization Webcasts from OOW Oct 2010 Oracle VDI 3.2 Overview Sep 2010 Blog Usability Top 7 Sep 2010 100 and counting Aug 2010 Oracle'izing the VDI Blogs Aug 2010 SocialChat on Apple Aug 2010 SocialChat on Video Conferencing Aug 2010 Oracle VDI 3.2 - Features and Screenshots Aug 2010 SocialChat: Don't stop making waves Aug 2010 SocialChat: Giving Back to the Community Aug 2010 SocialChat on Learning in Meetings Aug 2010 iPAD's Natural User Interface Jul 2010 Last day for Sun Microsystems GmbH Jun 2010 SirValUse Celebration Snippets Jun 2010 10 years SirValUse - Happy Birthday! Jun 2010 Wim on Virtualization May 2010 New Home for Oracle VDI Apr 2010 Renaissance Slide Sorter Comments Apr 2010 Unboxing Sun Ray 3 Plus Apr 2010 Desktop Virtualisierung mit Sun VDI 3.1 Apr 2010 Blog Relaunch Mar 2010 Social Messaging Slides from CeBIT Mar 2010 Social Messaging Talk at CeBIT Feb 2010 Welcome Oracle Jan 2010 My last presentation at Sun Jan 2010 Ivan Sutherland on Leadership Jan 2010 Learning French with Sun VDI Jan 2010 Learning Danish with Sun Ray Jan 2010 VDI workshop in Nieuwegein Jan 2010 Happy New Year 2010 Jan 2010 On Creating Slides Dec 2009 Best VDI Ever Nov 2009 How to store the Big Bang Nov 2009 Social Enterprise Tools. Beipiel Sun. Nov 2009 Nov-19 Nov 2009 PDF and ODF links on your blog Nov 2009 Q&A on VDI and MySQL Cluster Nov 2009 Zürich next week: Swiss Intranet Summit 09 Nov 2009 Designing for a Sustainable World - World Usabiltiy Day, Nov-12 Nov 2009 How to export a desktop from VDI 3 Nov 2009 Virtualisation Roadshow in the UK Nov 2009 Project Wonderland at EDUCAUSE 09 Nov 2009 VDI Roadshow in Dublin, Nov-26, 2009 Nov 2009 Sun VDI at EDUCAUSE 09 Nov 2009 Sun VDI 3.1 Architecture and New Features Oct 2009 VDI 3.1 is Early-Access Sep 2009 Virtualization for MySQL on VMware Sep 2009 Silpion & 13. Stock Sommerparty Sep 2009 Sun Ray and VMware View 3.1.1 2009-08-31 New Set of Sun Ray Status Icons 2009-08-25 Virtualizing the VDI Core? 2009-08-23 World Usability Day Hamburg 2009 - CfP 2009-07-16 Rising Sun 2009-07-15 featuring twittermeme 2009-06-19 ISC09 Student Party on June-20 /Hamburg 2009-06-18 Before and behind the curtain of JavaOne 2009-06-09 20k desktops at JavaOne 2009-06-01 sweet microblogging 2009-05-25 VDI 3 - Why you need 3 VDI hosts and what you can do about that? 2009-05-21 IA Konferenz 2009 2009-05-20 Sun VDI 3 UX Story - Power of the Web 2009-05-06 Planet of Sun and Oracle User Experience Design 2009-04-22 Sun VDI 3 UX Story - User Research 2009-04-08 Sun VDI 3 UX Story - Concept Workshops 2009-04-06 Localized documentation for Sun Ray Connector for VMware View Manager 1.1 2009-04-03 Sun VDI 3 Press Release 2009-03-25 Sun VDI 3 launches today! 2009-03-25 Sun Ray Connector for VMware View Manager 1.1 Update 2009-03-11 desktop virtualization wiki relaunch 2009-03-06 VDI 3 at CeBIT hall 6, booth E36 2009-03-02 Keyboard layout problems with Sun Ray Connector for VMware VDM 2009-02-23 wikis.sun.com tips & tricks 2009-02-23 Sun VDI 3 is in Early Access 2009-02-09 VirtualCenter unable to decrypt passwords 2009-02-02 Sun & VMware Desktop Training 2009-01-30 VDI at next09? 2009-01-16 Sun VDI: How to use virtual machines with multiple network adapters 2009-01-07 Sun Ray and VMware View 2009-01-07 Hamburg World Usability Day 2008 - Webcasts 2009-01-06 Sun Ray Connector for VMware VDM slides 2008-12-15 mother of all demos 2008-12-08 Build your own Thumper 2008-12-03 Troubleshooting Sun Ray Connector for VMware VDM 2008-12-02 My Roller Tag Cloud 2008-11-28 Sun Ray Connector: SSL connection to VDM 2008-11-25 Setting up SSL and Sun Ray Connector for VMware VDM 2008-11-13 Inspiration for Today and Tomorrow 2008-10-23 Sun Ray Connector for VMware VDM released 2008-10-14 From Sketchpad to ILoveSketch 2008-10-09 Desktop Virtualization on Xing 2008-10-06 User Experience Forum on Xing 2008-10-06 Sun Ray Connector for VMware VDM certified 2008-09-17 Virtual Clouds over Las Vegas 2008-09-14 Bill Verplank sketches metaphors 2008-09-04 End of Early Access - Sun Ray Connector for VMware 2008-08-27 Early Access: Sun Ray Connector for VMware Virtual Desktop Manager 2008-08-12 Sun Virtual Desktop Connector - Insides on Recycling Part 2 2008-07-20 Sun Virtual Desktop Connector - Insides on Recycling Part 3 2008-07-20 Sun Virtual Desktop Connector - Insides on Recycling 2008-07-20 lost in wiki space 2008-07-07 Evolution of the Desktop 2008-06-17 Virtual Desktop Webcast 2008-06-16 Woodstock 2008-06-16 What's a Desktop PC anyway? 2008-06-09 Virtual-T-Box 2008-06-05 Virtualization Glossary 2008-05-06 Five User Experience Principles 2008-04-25 Virtualization News Feed 2008-04-21 Acetylcholinesterase - Second Season 2008-04-18 Acetylcholinesterase - End of Signal 2007-12-31 Produkt-Management ist... 2007-10-22 Usability Verbände, Verteiler und Netzwerke. 2007-10-02 The Meaning is the Message 2007-09-28 Visualization Methods 2007-09-10 Inhouse und Open Source Projekte – Usability verankern und Synergien nutzen 2007-09-03 Der Schwabe Darth Vader entdeckt das Virale Marketing 2007-08-29 Dick Hardt 3.0 on Identity 2.0 2007-08-27 quality of written text depends on the tool 2007-07-27 podcasts for reboot9 2007-06-04 It is the user's itch that need to be scratched 2007-05-25 A duel at reboot9 2007-05-14 Taxonomien und Folksonomien - Tagging als neues HCI-Element 2007-05-10 Dueling Interaction Models of Personal-Computing and Web-Computing 2007-03-01 22.März: Weizenbaum. Rebel at Work. /Filmpremiere Hamburg 2007-02-25 Bruce Sterling at UbiComp 2006 /webcast 2006-11-12 FSOSS 2006 /webcasts 2006-11-10 Highway 101 2006-11-09 User Experience Roundtable Hamburg: EuroGEL 2006 2006-11-08 Douglas Adams' Hyperland (BBC 1990) 2006-10-08 Taxonomien und Folksonomien – Tagging als neues HCI-Element 2006-09-13 Usability im Unternehmen 2006-09-13 Doug does HyperScope 2006-08-26 TED Talks and TechTalks 2006-08-21 Kai Krause über seine Freundschaft zu Douglas Adams 2006-07-20 Rebel At Work: Film Portrait on Weizenbaum 2006-07-04 Gabriele Fischer, mp3 2006-06-07 Dick Hardt at ETech 06 2006-06-05 Weinberger: From Control to Conversation 2006-04-16 Eye Tracking at User Experience Roundtable Hamburg 2006-04-14 dropping knowledge 2006-04-09 GEL 2005 2006-03-13 slide photos of reboot7 2006-03-04 Dick Hardt on Identity 2.0 2006-02-28 User Experience Newsletter #13: Versioning 2006-02-03 Ester Dyson on Choice and Happyness 2006-02-02 Requirements-Engineering im Spannungsfeld von Individual- und Produktsoftware 2006-01-15 User Experience Newsletter #12: Intuition Quiz 2005-11-30 User Experience und Requirements-Engineering für Software-Projekte 2005-10-31 Ivan Sutherland on "Research and Fun" 2005-10-18 Ars Electronica / Mensch und Computer 2005 2005-09-14 60 Jahre nach Memex: Über die Unvereinbarkeit von Desktop- und Web-Paradigma 2005-08-31 reboot 7 2005-06-30

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  • Desktop Fun: Dual Monitor Wallpaper Collection Series 2

    - by Asian Angel
    Last month we brought you the first batch of wallpapers geared specifically towards dual monitor setups. Today we present the second offering in our series of dual monitor wallpaper collections. Note: Click on the picture to see the full-size image—these wallpapers vary in size so you may need to crop, stretch, or place them on a colored background in order to best match them to your screen’s resolution. More Dual Monitor Goodness Desktop Fun: Dual Monitor Wallpaper Collection Series 1 Span the same wallpaper across two monitors or use a different wallpaper for each. Dual Monitors: Use a Different Wallpaper on Each Desktop in Windows 7, Vista or XP For more wallpapers be certain to see our great collections in the Desktop Fun section. Latest Features How-To Geek ETC The 20 Best How-To Geek Linux Articles of 2010 The 50 Best How-To Geek Windows Articles of 2010 The 20 Best How-To Geek Explainer Topics for 2010 How to Disable Caps Lock Key in Windows 7 or Vista How to Use the Avira Rescue CD to Clean Your Infected PC The Complete List of iPad Tips, Tricks, and Tutorials Tune Pop Enhances Android Music Notifications Another Busy Night in Gotham City Wallpaper Classic Super Mario Brothers Theme for Chrome and Iron Experimental Firefox Builds Put Tabs on the Title Bar (Available for Download) Android Trojan Found in the Wild Chaos, Panic, and Disorder Wallpaper

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  • "Translator by Moth"

    - by Daniel Moth
    This article serves as the manual for the free Windows Phone 7 app called "Translator by Moth". The app is available from the following link (browse the link on your Window Phone 7 phone, or from your PC with zune software installed): http://social.zune.net/redirect?type=phoneApp&id=bcd09f8e-8211-e011-9264-00237de2db9e   Startup At startup the app makes a connection to the bing Microsoft Translator service to retrieve the available languages, and also which languages offer playback support (two network calls total). It populates with the results the two list pickers ("from" and "to") on the "current" page. If for whatever reason the network call fails, you are informed via a message box, and the app keeps trying to make a connection every few seconds. When it eventually succeeds, the language pickers on the "current" page get updated. Until it succeeds, the language pickers remain blank and hence no new translations are possible. As you can guess, if the Microsoft Translation service add more languages for textual translation (or enables more for playback) the app will automatically pick those up. "current" page The "current" page is the main page of the app with language pickers, translation boxes and the application bar. Language list pickers The "current" page allows you to pick the "from" and "to" languages, which are populated at start time. Until these language get populated with the results of the network calls, they remain empty and disabled. When enabled, tapping on either of them brings up on a full screen popup the list of languages to pick from, formatted as English Name followed by Native Name (when the latter is known). The "to" list, in addition to the language names, indicates which languages have playback support via a * in front of the language name. When making a selection for the "to" language, and if there is text entered for translation, a translation is performed (so there is no need to tap on the "translate" application bar button). Note that both language choices are remembered between different launches of the application.   text for translation The textbox where you enter the translation is always enabled. When there is nothing entered in it, it displays (centered and in italics) text prompting you to enter some text for translation. When you tap on it, the prompt text disappears and it becomes truly empty, waiting for input via the keyboard that automatically pops up. The text you type is left aligned and not in italic font. The keyboard shows suggestions of text as you type. The keyboard can be dismissed either by tapping somewhere else on the screen, or via tapping on the Windows Phone hardware "back" button, or via taping on the "enter" key. In the latter case (tapping on the "enter" key), if there was text entered and if the "from" language is not blank, a translation is performed (so there is no need to tap on the "translate" application bar button). The last text entered is remembered between application launches. translated text The translated text appears below the "to" language (left aligned in normal font). Until a translation is performed, there is a message in that space informing you of what to expect (translation appearing there). When the "current" page is cleared via the "clear" application bar button, the translated text reverts back to the message. Note a subtle point: when a translation has been performed and subsequently you change the "from" language or the text for translation, the translated text remains in place but is now in italic font (attempting to indicate that it may be out of date). In any case, this text is not remembered between application launches. application bar buttons and menus There are 4 application bar buttons and 4 application bar menus. "translate" button takes the text for translation and translates it to the translated text, via a single network call to the bing Microsoft Translator service. If the network call fails, the user is informed via a message box. The button is disabled when there is no "from" language available or when there is not text for translation entered. "play" button takes the translated text and plays it out loud in a native speaker's voice (of the "to" language), via a single network call to the bing Microsoft Translator service. If the network call fails, the user is informed via a message box. The button is disabled when there is no "to" language available or when there is no translated text available. "clear" button clears any user text entered in the text for translation box and any translation present in the translated text box. If both of those are already empty, the button is disabled. It also stops any playback if there is one in flight. "save" button saves the entire translation ("from" language, "to" language, text for translation, and translated text) to the bottom of the "saved" page (described later), and simultaneously switches to the "saved" page. The button is disabled if there is no translation or the translation is not up to date (i.e. one of the elements have been changed). "swap to and from languages" menu swaps around the "from" and "to" languages. It also takes the translated text and inserts it in the text for translation area. The translated text area becomes blank. The menu is disabled when there is no "from" and "to" language info. "send translation via sms" menu takes the translated text and creates an SMS message containing it. The menu is disabled when there is no translation present. "send translation via email" menu takes the translated text and creates an email message containing it (after you choose which email account you want to use). The menu is disabled when there is no translation present. "about" menu shows the "about" page described later. "saved" page The "saved" page is initially empty. You can add translations to it by translating text on the "current" page and then tapping the application bar "save" button. Once a translation appears in the list, you can read it all offline (both the "from" and "to" text). Thus, you can create your own phrasebook list, which is remembered between application launches (it is stored on your device). To listen to the translation, simply tap on it – this is only available for languages that support playback, as indicated by the * in front of them. The sound is retrieved via a single network call to the bing Microsoft Translator service (if it fails an appropriate message is displayed in a message box). Tap and hold on a saved translation to bring up a context menu with 4 items: "move to top" menu moves the selected item to the top of the saved list (and scrolls there so it is still in view) "copy to current" menu takes the "from" and "to" information (language and text), and populates the "current" page with it (switching at the same time to the current page). This allows you to make tweaks to the translation (text or languages) and potentially save it back as a new item. Note that the action makes a copy of the translation, so you are not actually editing the existing saved translation (which remains intact). "delete" menu deletes the selected translation. "delete all" menu deletes all saved translations from the "saved" page – there is no way to get that info back other than re-entering it, so be cautious. Note: Once playback of a translation has been retrieved via a network call, Windows Phone 7 caches the results. What this means is that as long as you play a saved translation once, it is likely that it will be available to you for some time, even when there is no network connection.   "about" page The "about" page provides some textual information (that you can view in the screenshot) including a link to the creator's blog (that you can follow on your Windows Phone 7 device). Use that link to discover the email for any feedback. Other UI design info As you can see in the screenshots above, "Translator by Moth" has been designed from scratch for Windows Phone 7, using the nice pivot control and application bar. It also supports both portrait and landscape orientations, and looks equally good in both the light and the dark theme. Other than the default black and white colors, it uses the user's chosen accent color (which is blue in the screenshot examples above). Feedback and support Please report (via the email on the blog) any bugs you encounter or opportunities for performance improvements and they will be fixed in the next update. Suggestions for new features will be considered, but given that the app is FREE, no promises are made. If you like the app, don't forget to rate "Translator by Moth" on the marketplace. Comments about this post welcome at the original blog.

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  • Problem with installing Pear (XAMPP)

    - by sanders
    Hello I installed the latest version of XAMPP (1.7.4) on my windows xp system. Now when i want to install Pear: k:\xampp\php>go-pear.bat I am confronted with the following error: manifest cannot be larger than 100 MB in phar "K:\xampp\php\PEAR\go-pear.phar"PH P Warning: require_once(phar://go-pear.phar/index.php): failed to open stream: phar error: invalid url or non-existent phar "phar://go-pear.phar/index.php" in K:\xampp\php\PEAR\go-pear.phar on line 1236 Warning: require_once(phar://go-pear.phar/index.php): failed to open stream: pha r error: invalid url or non-existent phar "phar://go-pear.phar/index.php" in K:\ xampp\php\PEAR\go-pear.phar on line 1236 Press any key to continue Line 1236 on in the go-pear.phar is this: require_once 'phar://go-pear.phar/index.php'; __HALT_COMPILER();< And after the last < there is a weird character sign. And if i take away that charachter I can't it doesn't help. She the image below for the character. Any help is very much appreciated.

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  • SQLAuthority News – Fast Track Data Warehouse 3.0 Reference Guide

    - by pinaldave
    http://msdn.microsoft.com/en-us/library/gg605238.aspx I am very excited that Fast Track Data Warehouse 3.0 reference guide has been announced. As a consultant I have always enjoyed working with Fast Track Data Warehouse project as it truly expresses the potential of the SQL Server Engine. Here is few details of the enhancement of the Fast Track Data Warehouse 3.0 reference architecture. The SQL Server Fast Track Data Warehouse initiative provides a basic methodology and concrete examples for the deployment of balanced hardware and database configuration for a data warehousing workload. Balance is measured across the key components of a SQL Server installation; storage, server, application settings, and configuration settings for each component are evaluated. Description Note FTDW 3.0 Architecture Basic component architecture for FT 3.0 based systems. New Memory Guidelines Minimum and maximum tested memory configurations by server socket count. Additional Startup Options Notes for T-834 and setting for Lock Pages in Memory. Storage Configuration RAID1+0 now standard (RAID1 was used in FT 2.0). Evaluating Fragmentation Query provided for evaluating logical fragmentation. Loading Data Additional options for CI table loads. MCR Additional detail and explanation of FTDW MCR Rating. Read white paper on fast track data warehousing. Reference: Pinal Dave (http://blog.SQLAuthority.com)   Filed under: Business Intelligence, Data Warehousing, PostADay, SQL, SQL Authority, SQL Documentation, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, SQLAuthority News, T SQL, Technology

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  • SQL SERVER – Concurrency Basics – Guest Post by Vinod Kumar

    - by pinaldave
    This guest post is by Vinod Kumar. Vinod Kumar has worked with SQL Server extensively since joining the industry over a decade ago. Working on various versions from SQL Server 7.0, Oracle 7.3 and other database technologies – he now works with the Microsoft Technology Center (MTC) as a Technology Architect. Let us read the blog post in Vinod’s own voice. Learning is always fun when it comes to SQL Server and learning the basics again can be more fun. I did write about Transaction Logs and recovery over my blogs and the concept of simplifying the basics is a challenge. In the real world we always see checks and queues for a process – say railway reservation, banks, customer supports etc there is a process of line and queue to facilitate everyone. Shorter the queue higher is the efficiency of system (a.k.a higher is the concurrency). Every database does implement this using checks like locking, blocking mechanisms and they implement the standards in a way to facilitate higher concurrency. In this post, let us talk about the topic of Concurrency and what are the various aspects that one needs to know about concurrency inside SQL Server. Let us learn the concepts as one-liners: Concurrency can be defined as the ability of multiple processes to access or change shared data at the same time. The greater the number of concurrent user processes that can be active without interfering with each other, the greater the concurrency of the database system. Concurrency is reduced when a process that is changing data prevents other processes from reading that data or when a process that is reading data prevents other processes from changing that data. Concurrency is also affected when multiple processes are attempting to change the same data simultaneously. Two approaches to managing concurrent data access: Optimistic Concurrency Model Pessimistic Concurrency Model Concurrency Models Pessimistic Concurrency Default behavior: acquire locks to block access to data that another process is using. Assumes that enough data modification operations are in the system that any given read operation is likely affected by a data modification made by another user (assumes conflicts will occur). Avoids conflicts by acquiring a lock on data being read so no other processes can modify that data. Also acquires locks on data being modified so no other processes can access the data for either reading or modifying. Readers block writer, writers block readers and writers. Optimistic Concurrency Assumes that there are sufficiently few conflicting data modification operations in the system that any single transaction is unlikely to modify data that another transaction is modifying. Default behavior of optimistic concurrency is to use row versioning to allow data readers to see the state of the data before the modification occurs. Older versions of the data are saved so a process reading data can see the data as it was when the process started reading and not affected by any changes being made to that data. Processes modifying the data is unaffected by processes reading the data because the reader is accessing a saved version of the data rows. Readers do not block writers and writers do not block readers, but, writers can and will block writers. Transaction Processing A transaction is the basic unit of work in SQL Server. Transaction consists of SQL commands that read and update the database but the update is not considered final until a COMMIT command is issued (at least for an explicit transaction: marked with a BEGIN TRAN and the end is marked by a COMMIT TRAN or ROLLBACK TRAN). Transactions must exhibit all the ACID properties of a transaction. ACID Properties Transaction processing must guarantee the consistency and recoverability of SQL Server databases. Ensures all transactions are performed as a single unit of work regardless of hardware or system failure. A – Atomicity C – Consistency I – Isolation D- Durability Atomicity: Each transaction is treated as all or nothing – it either commits or aborts. Consistency: ensures that a transaction won’t allow the system to arrive at an incorrect logical state – the data must always be logically correct.  Consistency is honored even in the event of a system failure. Isolation: separates concurrent transactions from the updates of other incomplete transactions. SQL Server accomplishes isolation among transactions by locking data or creating row versions. Durability: After a transaction commits, the durability property ensures that the effects of the transaction persist even if a system failure occurs. If a system failure occurs while a transaction is in progress, the transaction is completely undone, leaving no partial effects on data. Transaction Dependencies In addition to supporting all four ACID properties, a transaction might exhibit few other behaviors (known as dependency problems or consistency problems). Lost Updates: Occur when two processes read the same data and both manipulate the data, changing its value and then both try to update the original data to the new value. The second process might overwrite the first update completely. Dirty Reads: Occurs when a process reads uncommitted data. If one process has changed data but not yet committed the change, another process reading the data will read it in an inconsistent state. Non-repeatable Reads: A read is non-repeatable if a process might get different values when reading the same data in two reads within the same transaction. This can happen when another process changes the data in between the reads that the first process is doing. Phantoms: Occurs when membership in a set changes. It occurs if two SELECT operations using the same predicate in the same transaction return a different number of rows. Isolation Levels SQL Server supports 5 isolation levels that control the behavior of read operations. Read Uncommitted All behaviors except for lost updates are possible. Implemented by allowing the read operations to not take any locks, and because of this, it won’t be blocked by conflicting locks acquired by other processes. The process can read data that another process has modified but not yet committed. When using the read uncommitted isolation level and scanning an entire table, SQL Server can decide to do an allocation order scan (in page-number order) instead of a logical order scan (following page pointers). If another process doing concurrent operations changes data and move rows to a new location in the table, the allocation order scan can end up reading the same row twice. Also can happen if you have read a row before it is updated and then an update moves the row to a higher page number than your scan encounters later. Performing an allocation order scan under Read Uncommitted can cause you to miss a row completely – can happen when a row on a high page number that hasn’t been read yet is updated and moved to a lower page number that has already been read. Read Committed Two varieties of read committed isolation: optimistic and pessimistic (default). Ensures that a read never reads data that another application hasn’t committed. If another transaction is updating data and has exclusive locks on data, your transaction will have to wait for the locks to be released. Your transaction must put share locks on data that are visited, which means that data might be unavailable for others to use. A share lock doesn’t prevent others from reading but prevents them from updating. Read committed (snapshot) ensures that an operation never reads uncommitted data, but not by forcing other processes to wait. SQL Server generates a version of the changed row with its previous committed values. Data being changed is still locked but other processes can see the previous versions of the data as it was before the update operation began. Repeatable Read This is a Pessimistic isolation level. Ensures that if a transaction revisits data or a query is reissued the data doesn’t change. That is, issuing the same query twice within a transaction cannot pickup any changes to data values made by another user’s transaction because no changes can be made by other transactions. However, this does allow phantom rows to appear. Preventing non-repeatable read is a desirable safeguard but cost is that all shared locks in a transaction must be held until the completion of the transaction. Snapshot Snapshot Isolation (SI) is an optimistic isolation level. Allows for processes to read older versions of committed data if the current version is locked. Difference between snapshot and read committed has to do with how old the older versions have to be. It’s possible to have two transactions executing simultaneously that give us a result that is not possible in any serial execution. Serializable This is the strongest of the pessimistic isolation level. Adds to repeatable read isolation level by ensuring that if a query is reissued rows were not added in the interim, i.e, phantoms do not appear. Preventing phantoms is another desirable safeguard, but cost of this extra safeguard is similar to that of repeatable read – all shared locks in a transaction must be held until the transaction completes. In addition serializable isolation level requires that you lock data that has been read but also data that doesn’t exist. Ex: if a SELECT returned no rows, you want it to return no. rows when the query is reissued. This is implemented in SQL Server by a special kind of lock called the key-range lock. Key-range locks require that there be an index on the column that defines the range of values. If there is no index on the column, serializable isolation requires a table lock. Gets its name from the fact that running multiple serializable transactions at the same time is equivalent of running them one at a time. Now that we understand the basics of what concurrency is, the subsequent blog posts will try to bring out the basics around locking, blocking, deadlocks because they are the fundamental blocks that make concurrency possible. Now if you are with me – let us continue learning for SQL Server Locking Basics. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Concurrency

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