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• Roanoke Code Camp 2014

  - by Brian Lanham

  Originally posted on: http://geekswithblogs.net/codesailor/archive/2014/05/18/156407.aspxI had a great time yesterday at Roanoke Code Camp!  Many thanks to American National University for the venue, the code camp staff and volunteers, the other speakers, and of course the attendees who made my sessions interactive.  I learned a lot yesterday and it was a good time all around. I attended sessions on Apache Cassandra by Dr. Dave King (@tildedave), Angular JS by Kevin Israel (@kevadev), and JavaScript for Object-Oriented Programmers by Joel Cochran (@joelcochran).  I regret I was unable to attend all the sessions. I also had the opportunity to present.  I spoke on Redis and got some people excited about graph databases by talking about Neo4j.  You can find my slides and other materials at the following links: My Presentation Materials Folder Redis Materials – Slides     - Snippets Neo4j Materials – Slides     - Snippets If you have any trouble getting any of the materials just respond to this post or tweet me @codesailor and I will make sure you get the information you need.

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• Designing a social network with CQRS, graph databases and relational databases in mind

  - by Siraj Mansour

  I have done quite an amount of research on the topic so far, but i couldn't come up with a conclusion to make up my mind. I am designing a social network and during my research i stumbled upon graph databases, i found neo4j pretty interesting for user relations and traversing through nodes. I also thought of using a relational database such as MS-SQL or MySQL to store entity data only and depending on neo4j for connections between entities. Of course this means more work in my application to store and pull data in and out of 2 different sources. My first question : Is using this approach (graph + relational) a good approach for designing my social network keeping in mind that users on social networks don't have to in synch with real data by split second ? What are the positives and negatives of this approach ? My Second question : I've been doing some reading on CQRS and as i understood it is mostly useful for collaborative environments, and environments where users see a lot of "stale" data. social networks has shared comments, events, etc .. and many users query or update the same data. Could CQRS be a helpful approach ? Would it give any performance/scalability benefits or non-useful complexity ? Is it fairly applicable with my possible choice of (graph + relational) databases approach mentioned in the question above ? My purpose is to know if the approaches i have mentioned above seem good enough for the business context.

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• Graph database for .NET

  - by Antonello

  I've been designing an application, based on .NET/Mono framework, which should make an heavy use of the shortest-path in a graph theories and I would like to use a native solution to traverse the nodes of the graph, instead of implementing surrogate solutions which would be hardly maintainable and would massively affect performances. I've found an application which would be perfect for my scope: neo4j. Unfortunately, this application is purely written in Java code and it's not portable to .NET, because of the massive differences between the two architectures. Is anyone out there knows if is it there any port of neo4j or a similar solution for .NET?

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• How does I/O work for large graph databases?

  - by tjb1982

  I should preface this by saying that I'm mostly a front end web developer, trained as a musician, but over the past few years I've been getting more and more into computer science. So one idea I have as a fun toy project to learn about data structures and C programming was to design and implement my own very simple database that would manage an adjacency list of posts. I don't want SQL (maybe I'll do my own query language? I'm just having fun). It should support ACID. It should be capable of storing 1TB let's say. So with that, I was trying to think of how a database even stores data, without regard to data structures necessarily. I'm working on linux, and I've read that in that world "everything is a file," including hardware (like /dev/*), so I think that that obviously has to apply to a database, too, and it clearly does--whether it's MySQL or PostgreSQL or Neo4j, the database itself is a collection of files you can see in the filesystem. That said, there would come a point in scale where loading the entire database into primary memory just wouldn't work, so it doesn't make sense to design it with that mindset (I assume). However, reading from secondary memory would be much slower and regardless some portion of the database has to be in primary memory in order for you to be able to do anything with it. I read this post: Why use a database instead of just saving your data to disk? And I found it difficult to understand how other databases, like SQLite or Neo4j, read and write from secondary memory and are still very fast (faster, it would seem, than simply writing files to the filesystem as the above question suggests). It seems the key is indexing. But even indexes need to be stored in secondary memory. They are inherently smaller than the database itself, but indexes in a very large database might be prohibitively large, too. So my question is how is I/O generally done with large databases like the one I described above that would be at least 1TB storing a big adjacency list? If indexing is more or less the answer, how exactly does indexing work--what data structures should be involved?

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• CodePlex Daily Summary for Friday, May 21, 2010

  CodePlex Daily Summary for Friday, May 21, 2010New Projects.Net wrapper around the Neo4j Rest Server: Neo4jRestSharp is a .Net API wrapper for the Neo4j Rest Server. Neo4j is an open sourced java based transactional graph database that stores data ...3D Editor Application Framework: A starting point for building 3D editing applications, such as video game editors, particle system editors, 3D modelling tools, visualization tools...Bulk Actions for SharePoint: This project aims to provide some essential and generic bulk actions for SharePoint lists. Idea is to include any custom actions that can be applie...CineRemote - The hometheater control board: CineRemote's purpose is to offer an alternative to expensive control system for dedicated hometheater rooms. CrmContrib: CrmContrib is a collection of useful items for developers and customizers working with the Dynamics CRM platform.db2xls: OleDb,Sql Server,Sqlite,....to excel, from sqlHappyNet - Silverlight reference application: HappyNet is a project using best practices to build an e-commerce web site. It is a full Silverlight application based on a solid architecture (PR...IP Multicast Library: IP Multicast Library makes it easier for developers to add Multicast, messaging to projects.Linkbutton Web Part: This Link Button Web Part can be installed in any SharePoint 2007 web site. You can onfigure a URL with query string that will be used by the Link...Majordomus pro Windows: Nástroj určený pro správce a vývojáře slouží k řízenému spuštění používaných a vypnutí nepotřebných služeb, procesů a aplikací ve Windows. Pomocí s...MRDS Samples: The MRDS Samples site hosts a variety of code samples for Microsoft Robotics Developer Studio (RDS).Mute4: Mute4 is a simple application that allows you to set a mute/vibration profile and it will switch back to your normal profile automatically after a ...Niko Neko Pureya: Niko Neko Pureya is a media player designed for people who watches a series of videos (like anime). It is very simple and easy to use & learn. And ...NVPX - VP8 Video Codec for .Net: NVPx allows you to use the now open-source VP8 codec on the .Net platform.openrs: openrs is an open-source RuneScape 2 emulator designed to be used with newer engine clients.Prism Evaluation: prism evaluationProj4Net: Proj4Net is a C#/.Net library to transform point coordinates from one geographic coordinate system to another, including datum transformation. The ...Read it to me!: Read it to me will allow you to load txt and rtf files and then speak them using SAPI 5 voices that are installed on your computer with an option t...sGSHOPedit: -SilverDice: SilverDice...SilverDude Toolkit for Silverlight: SilverDude Toolkit for Silverlight contains a collection of silverlight controls making life easier for developers. You'll no longer have to worry ...Silverlight Report: Open-Source Silverlight Reporting Engine. This project allows you to create and print reports using Silverlight 4.SimTrain5000: Train simulation project on University College of Northern Denmark.Springshield Sample Site for EPiServer CMS: City of Springshield - The accessible sample site for EPiServer CMS 6.Teach.Net: Teach.Net is a library/framework that can be used to create applications for testing and learning.The Amoeba Project: The Amoeba Project is a platform to be developed to embrace most of the latest Microsoft Technologies. Still in a conceptual stage however, it loo...The Fastcopy Helper: The Fastcopy Helper is a auxiliary tool for fastcopy.vow: vowWCF Client Generator: This code generator avoids the shortcomings of svcutil when generating proxies for services with a large number of methods.WebCycle: WebCycle is a screensaver application that cycles through web pages. This was originally created to cycle through Reporting Services reports so th...XGate2D - XNA 2D Game Engine: XGate2D is 2D game engine built using XNA Framework. XGate2D currently has 8 features: input handler, animation, Graphical User Interface (GUI), ...XNA Catapult Minigame for XNA 4: XNA 4 implementation of the Catapult Minigame Sample from XNA Creators Club.New ReleasesADefHelpDesk: ADefHelpDesk (Standard ASP.NET Version) 01.00.00: ADefHelpDesk a Help Desk / Ticket Tracker module * NOTE: This version is NOT a DotNetNuke module - It is a standard ASP.NET Application * SQL 2005...Bulk Actions for SharePoint: First Release: First Release - Includes following bulk list actions: *Delete *Checkin/Checkout *Publish/Unpublish *Move *Update MetadataCheck-in Wizard for ArenaChMS: v1.2.1: v 1.2.0 updated to work with Arena 2009.2 (see notes below). Added support for "At Kiosk" and "At Location" printing. Added support for print l...ConfigTray: 1.5: Version 1.5 will have a new UI for managing ConfigTray config. Instead of manually editing configtray.exe.config to add/delete/edit settings and fi...CrmContrib: CrmContribWorkflow 1.0 ALPHA1: This is an initial release of the CrmContribWorkflow 1.0 components. At the moment there are only two activities included in this release. Add Cont...DemotToolkit: DemotToolkit-0.1.0.50830: Initial release.DemotToolkit: DemotToolkit-0.1.1.51107: Fixed crashing in some circumstances.Dot Game: Dot Game Stable Release: Dot Game This is latest stable release without network play mode. (Network play mode is under development)Dynamic Survey Forms - SharePoint Web Part: Fix for missing dlls and documentation: Added missing assemblies to setup.zip. Installation instructions.EnhSim: V1.9.8.7: Added Sharpened Twilight ScaleEvent Scavenger: Viewer 3.2.2: Fixed a bug in the viewer where the previous view 'Top x' filter was not restored after the application was reopened.F# Project Extender: V0.9.2.0 (VS2008,VS2010): F# project extender for Visual Studio 2008 and Visual Studio 2010. Fixed bugs: -VS2010 crash on MoveUp(MoveDown) of renamed file -Adding files brea...FlickrNet API Library: 3.0 Beta 2: The final Beta for the 3.0 release. Fixes a major issue with Photosets.GetList as well as a number of smaller bugs, and adds the new Usage extras ...Folder Bookmarks: Folder Bookmarks 1.5.7: The latest version of Folder Bookmarks (1.5.7), with the new Help feature - all the instructions needed to use the software (If you have any sugges...Linkbutton Web Part: V1.1: Use WinZip to unzip. See docs folder for installation instructions.Live-Exchange Calendar Sync: Live-Exchange Calendar Sync Final: Live-Exchange Calendar Sync Beta May 14, 2010 release of Live-Exchange Calendar Sync 1.0 . (Version 46127) Getting StartedInfo about installation ...MEFedMVVM: MEFedMVVM: This version contains the MEFedMVVM ViewModelLocator and also some basic services such as Mediator and StateManager. You can download the code fr...Mentor Text Database: May 2010 Release with instrumentation: This should function the same as the previous version. Some enhancements have been made, and additional instrumentation has been added to help anal...Merthin: SSF 2010: Code and documentation presented at the Student Science Fair of the Faculty of Mathematics and Computer Science at the University of Habana. The ma...NB_Store - Free DotNetNuke Ecommerce Catalog Module: NB_Store_02.01.00: NB_Store v2.1.0 THIS IS AN ALPHA RELEASE FOR TESTING ONLY......DO NOT USE IT ON A LIVE SYSTEM.NerdDinner.com - Where Geeks Eat: NerdDinner - Four Database Access Samples: Chris Sells worked with Nick Muhonen from Useable Concepts and Nick created four samples exploring how an ASP.NET MVC application can access databa...openrs: Devstart: Trunk release, empty project.Over Store: OverStore 1.19.0.0: - Version number is increased. - Add methods for specifying custom callback methods to TableMappingRepositoryConfiguration. - Object attaching fu...Rnwood.SmtpServer: Rnwood.SmtpServer 2.0: SmtpServer 2.0 is a .NET SMTP server component written in pure c#. It was written to power http://smtp4dev.codeplex.com/ but can easily be used by ...Scrum Sprint Monitor: v1.0.0.48524 (.NET 4-TFS 2010): What is new in this release? #6132 - Bug with open work hours; Added untested support for MSF for Agile process template; Improved data reporti...SharePoint Rsync List: 1.0.0.0: This initial 1.0 release includes a new feature which manages timer jobs on your sync listShould: Beta 1.1: Updated the namespaces. The extension methods are now in the root Should namespace. The other classes are not in child namespaces.SilverDude Toolkit for Silverlight: SilverDude Toolkit for Silverlight: Kindly give your comments about this project and tell how you feel about it. I'm still new in creating controls, hopefully you guys can support me....Silverlight Report: SilverlightReport_v0.1_alpha_bin: SilverlightReport v0.1 alphaSLARToolkit - Silverlight Augmented Reality Toolkit: SLARToolkit 1.0.2.0: Fixed a problem with long referenced DetectionResults that might have caused an IndexOutOfRangeException Added Marker.LoadFromResource to get rid...The Fastcopy Helper: My Fastcopy Helper 1.0: This Source Code Is use a method to run it . The method is thinked by my bain. So , The Performance maybe lower.Thinktecture.DataObjectModel: Thinktecture.DataObjectModel v0.12: Some bugs fixed. See ChangeLog.txt for more infos.Umbraco CMS: Umbraco 4.0.4.1: A stability release fixing 13 issues based on feedback from 4.0.3 users. Most importantly is a fix to a serious date bug where day and month could ...Usa*Usa Libraly: Smart.Web.Mobile ver 0.2: Smart.Web.Mobile pictgram convert library for japanese galapagos k-tai( ﾟдﾟ) ver 0.2. - Custom encoding for HttpRequest.ContentEncoding / HttpResp...VCC: Latest build, v2.1.30520.0: Automatic drop of latest buildvow: dream: I have a dreamvow: test: testWCF Client Generator: Version 0.9.1.42927: Initial feature set complete. Detailed UI pending.WebCycle: WebCycle 1.0.20: Initial CodePlex releaseWebCycle: WebCycle 1.0.21: Added Uri validataion before saving settingsWhois Application: 1.5 release: - uses the whois.iana.org to dynamically lookup the whois server for each top level domain - enables enter key press for searchWing Beats: Wing Beats 0.9: This first release is focused on the core functionality and XHTML 1.0 strict generation in Asp.NET MVC.Most Popular ProjectsWeb Service Software FactoryPlasmaAquisição de Sinais Vitais em Tempo Real (Vital signs realtime data acquisition)Octtree XNA-GS DrawableGameComponentRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)Most Active ProjectsRawrpatterns & practices – Enterprise LibraryGMap.NET - Great Maps for Windows Forms & PresentationPHPExcelBlogEngine.NETSQL Server PowerShell ExtensionsCaliburn: An Application Framework for WPF and SilverlightNB_Store - Free DotNetNuke Ecommerce Catalog Modulepatterns & practices: Windows Azure Security GuidanceFluent Ribbon Control Suite

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• Which technology is best suited to store and query a huge readonly graph?

  - by asmaier

  I have a huge directed graph: It consists of 1.6 million nodes and 30 million edges. I want the users to be able to find all the shortest connections (including incoming and outgoing edges) between two nodes of the graph (via a web interface). At the moment I have stored the graph in a PostgreSQL database. But that solution is not very efficient and elegant, I basically need to store all the edges of the graph twice (see my question PostgreSQL: How to optimize my database for storing and querying a huge graph). It was suggested to me to use a GraphDB like neo4j or AllegroGraph. However the free version of AllegroGraph is limited to 50 million nodes and also has a very high-level API (RDF), which seems too powerful and complex for my problem. Neo4j on the other hand has only a very low level API (and the python interface is not mature yet). Both of them seem to be more suited for problems, where nodes and edges are frequently added or removed to a graph. For a simple search on a graph, these GraphDBs seem to be too complex. One idea I had would be to "misuse" a search engine like Lucene for the job, since I'm basically only searching connections in a graph. Another idea would be, to have a server process, storing the whole graph (500MB to 1GB) in memory. The clients could then query the server process and could transverse the graph very quickly, since the graph is stored in memory. Is there an easy possibility to write such a server (preferably in Python) using some existing framework? Which technology would you use to store and query such a huge readonly graph?

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• How/where to run the algorithm on large dataset?

  - by niko

  I would like to run the PageRank algorithm on graph with 4 000 000 nodes and around 45 000 000 edges. Currently I use neo4j graph databse and classic relational database (postgres) and for software projects I mostly use C# and Java. Does anyone know what would be the best way to perform a PageRank computation on such graph? Is there any way to modify the PageRank algorithm in order to run it at home computer or server (48GB RAM) or is there any useful cloud service to push the data along the algorithm and retrieve the results? At this stage the project is at the research stage so in case of using cloud service if possible, would like to use such provider that doesn't require much administration and service setup, but instead focus just on running the algorith once and get the results without much overhead administration work.

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• What is the graph database that can scale out horizontally, handle large volumes of data, and perfor

  - by Student

  Which is the graph database that supports limitless scale out, handles large volumes of data, and can perform low-latency queries? Preferably one that integrates well with Hadoop. I have been reading about couple of products called Neo4J, AllegroGraph, and BigData. Please share your experiences with any of these.

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• CodePlex Daily Summary for Tuesday, October 02, 2012

  CodePlex Daily Summary for Tuesday, October 02, 2012Popular ReleasesZ3: Z3 4.1.1 source code: Snapshot corresponding to version 4.1.1.DirectX Tool Kit: October 2012: October 2, 2012 Added ScreenGrab module Added CreateGeoSphere for drawing a geodesic sphere Put DDSTextureLoader and WICTextureLoader into the DirectX C++ namespace Renamed project files for better naming consistency Updated WICTextureLoader for Windows 8 96bpp floating-point formats Win32 desktop projects updated to use Windows Vista (0x0600) rather than Windows 7 (0x0601) APIs Tweaked SpriteBatch.cpp to workaround ARM NEON compiler codegen bugHome Access Plus+: v8.1: HAP+ Web v8.1.1003.000079318 Fixed: Issue with the Help Desk and updating a ticket as an admin 79319 Fixed: formatting issue with the booking system admin header 79321 Moved to using the arrow with a circle symbol on the homepage instead of the > and < 79541 Added: 480px wide mobile theme to login page 79541 Added: 480px wide mobile theme to home page 79541 Added: slide events for homepage 79553 Fixed: Booking System Multiple Lesson Bug 79553 Fixed: IE Error Message 79684 Fixed: jQuery issue ...Tabular Database Powershell Cmdlets: AdventureWorks Tabular PowerShell 2012 test script: AdventureWorks Tabular PowerShell 2012.ps1 is a testing script to verify the functionality of the 'Tabular Database PowerShell Cmdlets'. This script recreates parts of AdventureWorks Tabular 2012 Model; to run the script you need access to a relational database and have access to 'AdventureWorksDW2012'.CRM 2011 Visual Ribbon Editor: Visual Ribbon Editor (1.3.1002.3): Visual Ribbon Editor 1.3.1002.3 What's New: Multi-language support for Labels/Tooltips for custom buttons and groups Support for base language other than English (1033) Connect dialog will not require organization name for ADFS / IFD connections Automatic creation of missing labels for all provisioned languages Minor connection issues fixed Notes: Before saving the ribbon to CRM server, editor will check Ribbon XML for any missing <Title> elements inside existing <LocLabel> elements...YAXLib: Yet Another XML Serialization Library for the .NET Framework: YAXLib 2.10: See change-log for the list of new features added and bugs fixedNaked Objects: Naked Objects Release 5.0.0: Corresponds to the packaged version 5.0.0 available via NuGet. Please note that the easiest way to install and run the Naked Objects Framework is via the NuGet package manager: just search the Official NuGet Package Source for 'nakedobjects'. It is only necessary to download the source code (from here) if you wish to modify or re-build the framework yourself. If you do wish to re-build the framework, consul the file HowToBuild.txt in the release. Major enhancementsNaked Objects 5.0 is desi...WinRT XAML Toolkit: WinRT XAML Toolkit - 1.3.0: WinRT XAML Toolkit based on the Windows 8 RTM SDK. Download the latest source from the SOURCE CODE page. For compiled version use NuGet. You can add it to your project in Visual Studio by going to View/Other Windows/Package Manager Console and entering: PM> Install-Package winrtxamltoolkit Features AsyncUI extensions Controls and control extensions Converters Debugging helpers Imaging IO helpers VisualTree helpers Samples Recent changes NOTE: Namespace changes DebugConsol...D3 Loot Tracker: 1.4.1: This version will automatically save a recording session on application exit if the user didn't stop the current session.Untangler: Untangler: First version of Untangler application available now.SubExtractor: Release 1029: Feature: Added option to make i and ¡ characters movie-specific for improved OCR on Spanish subs (Special Characters tab in Options) Feature: Allow switch to Word Spacing dialog directly from Spell Check dialog Fix: Added more default word spacings for accented characters Fix: Changed Word Spacing dialog to show all OCR'd characters in current sub Fix: Removed application focus grab during OCR Fix: Tightened HD subs fuzzy logic to reduce false matches in small characters Fix: Improved Arrow k...MCEBuddy 2.x: MCEBuddy 2.2.18: Reccomended download Changelog for 2.2.18 (32bit and 64bit) 1. Added support for checking if Showanalyzer has hung and cancelling it 2. New version of comskip, 0.81.48 3. Speeding up comskip 4. Fixed a build bug in 64bit 2.2.17 5. Added a new comkip.ini, better commercial detection for international channels and less aggressive. Old one has been retained as comskip_old.ini 6. Added support for Audio Offset on Conversion Task page in GUI (this overrides the profiles AudioDelay when specified)Mugen Injection: Mugen Injection 3.0: Added a generic version of the fluent syntax. Big changes in fluent-syntax. Added support to resolve a parameters: - Factory: AnyCustomFunc{T}, AnyCustomFunc{IEnumerable<IInjectionParameters>,T}, AnyCustomFunc{IDictionary<string, object>,T}, AnyCustomFunc{IEnumerable<IInjectionParameters>,IDictionary<string, object>,T} - Lazy: AnyCustomLazy<T> - Binding metadata: ISetting Change binding builders, now you can configure them through the string settings. Increase performance. F...Readable Passphrase Generator: KeePass Plugin 0.7.1: See the KeePass Plugin Step By Step Guide for instructions on how to install the plugin. Changes Built against KeePass 2.20Pentagon-XnaGamePrototype: Pentagon_Application: -Windows 8 Toolkit - Charts and More: Beta 1.0: The First Compiled Version of my LibraryPDF.NET: PDF.NET.Ver4.5-OpenSourceCode: PDF.NET Ver4.5 ????，????Web??????。 PDF.NET Ver4.5 Open Source Code,include a sample Web application project.Visual Studio Icon Patcher: Version 1.5.2: This version contains no new images from v1.5.1 Contains the following improvements: Better support for detecting the installed languages The extract & inject commands won’t run if Visual Studio is running You may now run in extract or inject mode The p/invoke code was cleaned up based on Code Analysis recommendations When a p/invoke method fails the Win32 error message is now displayed Error messages use red text Status messages use green textZXing.Net: ZXing.Net 0.9.0.0: On the way to a release 1.0 the API should be stable now with this version. sync with rev. 2393 of the java version improved api better Unity support Windows RT binaries Windows CE binaries new Windows Service demo new WPF demo WindowsCE Hotfix: Fixes an error with ISO8859-1 encoding and scannning of QR-Codes. The hotfix is only needed for the WindowsCE platform.Picturethrill: Version 2.9.25.0: Allowing to run Picturethrill Update task while computer is not connected to internet on computer wake up.New ProjectsAssociativy Neo4j Driver: Neo4j graph database driver for Associativy. See: http://associativy.comCalcSig: Utility for identifying near-duplicate audio and image files.CTODO: TODO List management utilityEstudosSedna: goto HomeFun-Beat: Fun-Beat is a free XAudio2 based Drum-Machine/synthesizer in its initial phasesgbtest: This is a demoGlobal Stock Exchange (Hobby Project): GSE is sort of a hobby project. Global Stock Exchange has a rich dynamic UI. A number of concurrent multi-threaded actions are going on behind the scene.HealthVault Library for Windows 8: This library provides a simple framework for building Windows Store applications that connect to Microsoft HealthVault. Homework management: Házi feladat beadó rendszer megvalósításaHostalApp: Proyecto de Taller de Sistemas de InformacionIIS Logfile Archiving: IIS instances log website activity to disk. Let's archive those files for later in a .zip file.Impact Bootstrap For Windows 8: Impact Bootstrap for Windows 8 is a simple collection of scripts, code and stock art/sounds that can help you create HTML5 games on Windows 8 faster.Innovacall ASP.net MVC 3 Framework and Starter Kits: Innovacall Open Source Development Framework for Asp.Net MVC 3.1.JRFinances: Financial project for university graduationLazyField Demo: A demo module demonstrating the LazyField<T> class in Orchard.Lilith: Linux libraryManaged Metadata Migrator: Move term sets across SharePoint farms, managed metadata service applications or groups with term GUIDs intact.MyFamily: An ASP.net application for families to share pictures/videos/events with one anotherNengraphy: Nengraphy Gentoo OverlayOrchard CMS Image MultiPicker Field: This module provides image multi picker field for Orchard CMS 1.5.1.PDFWebViewer.NET 1.0: As of October 1st, 2012 TallComponents has discontinued PDFWebViewer.NET 1.0. This project publishes the 1.0.21.0 source code.PromikeHomeSite: My home site.Sharepoint Dynamic Quicklaunch: Sharepoint Dynamic Quicklaunch is a jquery plugin to generate dynamic menus for the Sharepoint 2010 Quicklaunch. Slider - Simple Slideshow Solution: Highly customizable slideshow solution for any website.TypeScript: TypeScript is a language for application-scale JavaScript development. TypeScript is a typed superset of JavaScript that compiles to plain JavaScript.Velocity4Net: translated from apache velocity 1.7WebViewer.NET 2.0: As of October 1st, 2012 TallComponents has discontinued WebViewer.NET 2.0. This project publishes the 2.0.0.3 source code.WireBear InfoPath Printer: Adds a print button to the ribbon for InfoPath List Display Forms in SharePoint 2010.YingEngine2: ??????????????。 ??????????，???，???????RPG??。?????????????????，???????????????????，???????????。

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• How do you keep down your urge to learn many things [closed]

  - by devsundar

  One of the difficulties i have is to lower my urge to learn new things (Languages, tools, frameworks etc.). I know it's good to stay the bleeding edge, but at the same time i want to learn things properly. I really see that i need to strike a balance between staying bleeding edge and knowing things properly. For example: Before choosing Arch (Desktop), Ubuntu(Server) and Knoppix(Portable) -- depending on situation -- as favourite distributions. Virtually i have tried all popular linux distributions. You name any popular linux (Redhat, Ubuntu, Arch, Suse, Knoppix, Slax, Slackware) i have tried it for some time. In fact i have spent few years experimenting the operating systems. Before choosing Python, Javascript (nodejs). I have tried all the languages i cameacross Scala, Haskell, Erlang, Ruby, Python, Perl, Scheme. Same applies for database. All popular db RDBMS (Oracle, Mysql, Postgres, SQLite[Favourite] etc) and NoSQL (Mongo, Couch, Neo4j etc.). Advantages i see: We get a overall picture of the technologies/tools/languages. It's useful to select the right tool for the job. We develop a taste and choose the One we like. Disadvantages: I feel that i spend somuch time and see a need to strike a balance. In summary, for e.g. If i see a blog post in HackerNews about CofeeScript i will try it out irrespective of what i am currently learning (Say Haskell). I switch back to learning Haskell, then again i see DART i check it out. And this continues.. Effectively i take more time to learn Haskell, but learnt about other new stuff on the way. The quetion i have is how do you strike a balance between staying bleeding edge and learning properly.

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

  - by Pinal Dave

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

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• Big Data: Size isn’t everything

  - by Simon Elliston Ball

  Big Data has a big problem; it’s the word “Big”. These days, a quick Google search will uncover terabytes of negative opinion about the futility of relying on huge volumes of data to produce magical, meaningful insight. There are also many clichéd but correct assertions about the difficulties of correlation versus causation, in massive data sets. In reading some of these pieces, I begin to understand how climatologists must feel when people complain ironically about “global warming” during snowfall. Big Data has a name problem. There is a lot more to it than size. Shape, Speed, and…err…Veracity are also key elements (now I understand why Gartner and the gang went with V’s instead of S’s). The need to handle data of different shapes (Variety) is not new. Data developers have always had to mold strange-shaped data into our reporting systems, integrating with semi-structured sources, and even straying into full-text searching. However, what we lacked was an easy way to add semi-structured and unstructured data to our arsenal. New “Big Data” tools such as MongoDB, and other NoSQL (Not Only SQL) databases, or a graph database like Neo4J, fill this gap. Still, to many, they simply introduce noise to the clean signal that is their sensibly normalized data structures. What about speed (Velocity)? It’s not just high frequency trading that generates data faster than a single system can handle. Many other applications need to make trade-offs that traditional databases won’t, in order to cope with high data insert speeds, or to extract quickly the required information from data streams. Unfortunately, many people equate Big Data with the Hadoop platform, whose batch driven queries and job processing queues have little to do with “velocity”. StreamInsight, Esper and Tibco BusinessEvents are examples of Big Data tools designed to handle high-velocity data streams. Again, the name doesn’t do the discipline of Big Data any favors. Ultimately, though, does analyzing fast moving data produce insights as useful as the ones we get through a more considered approach, enabled by traditional BI? Finally, we have Veracity and Value. In many ways, these additions to the classic Volume, Velocity and Variety trio acknowledge the criticism that without high-quality data and genuinely valuable outputs then data, big or otherwise, is worthless. As a discipline, Big Data has recognized this, and data quality and cleaning tools are starting to appear to support it. Rather than simply decrying the irrelevance of Volume, we need as a profession to focus how to improve Veracity and Value. Perhaps we should just declare the ‘Big’ silent, embrace these new data tools and help develop better practices for their use, just as we did the good old RDBMS? What does Big Data mean to you? Which V gives your business the most pain, or the most value? Do you see these new tools as a useful addition to the BI toolbox, or are they just enabling a dangerous trend to find ghosts in the noise?

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• Big Data – Operational Databases Supporting Big Data – Columnar, Graph and Spatial Database – Day 14 of 21

  - by Pinal Dave

  In yesterday’s blog post we learned the importance of the Key-Value Pair Databases and Document Databases in the Big Data Story. In this article we will understand the role of Columnar, Graph and Spatial Database supporting Big Data Story. Now we will see a few of the examples of the operational databases. Relational Databases (The day before yesterday’s post) NoSQL Databases (The day before yesterday’s post) Key-Value Pair Databases (Yesterday’s post) Document Databases (Yesterday’s post) Columnar Databases (Tomorrow’s post) Graph Databases (Today’s post) Spatial Databases (Today’s post) Columnar Databases  Relational Database is a row store database or a row oriented database. Columnar databases are column oriented or column store databases. As we discussed earlier in Big Data we have different kinds of data and we need to store different kinds of data in the database. When we have columnar database it is very easy to do so as we can just add a new column to the columnar database. HBase is one of the most popular columnar databases. It uses Hadoop file system and MapReduce for its core data storage. However, remember this is not a good solution for every application. This is particularly good for the database where there is high volume incremental data is gathered and processed. Graph Databases For a highly interconnected data it is suitable to use Graph Database. This database has node relationship structure. Nodes and relationships contain a Key Value Pair where data is stored. The major advantage of this database is that it supports faster navigation among various relationships. For example, Facebook uses a graph database to list and demonstrate various relationships between users. Neo4J is one of the most popular open source graph database. One of the major dis-advantage of the Graph Database is that it is not possible to self-reference (self joins in the RDBMS terms) and there might be real world scenarios where this might be required and graph database does not support it. Spatial Databases  We all use Foursquare, Google+ as well Facebook Check-ins for location aware check-ins. All the location aware applications figure out the position of the phone with the help of Global Positioning System (GPS). Think about it, so many different users at different location in the world and checking-in all together. Additionally, the applications now feature reach and users are demanding more and more information from them, for example like movies, coffee shop or places see. They are all running with the help of Spatial Databases. Spatial data are standardize by the Open Geospatial Consortium known as OGC. Spatial data helps answering many interesting questions like “Distance between two locations, area of interesting places etc.” When we think of it, it is very clear that handing spatial data and returning meaningful result is one big task when there are millions of users moving dynamically from one place to another place & requesting various spatial information. PostGIS/OpenGIS suite is very popular spatial database. It runs as a layer implementation on the RDBMS PostgreSQL. This makes it totally unique as it offers best from both the worlds. Courtesy: mushroom network Tomorrow In tomorrow’s blog post we will discuss about very important components of the Big Data Ecosystem – Hive. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• What scalability problems have you solved using a NoSQL data store?

  - by knorv

  NoSQL refers to non-relational data stores that break with the history of relational databases and ACID guarantees. Popular open source NoSQL data stores include: Cassandra (tabular, written in Java, used by Facebook, Twitter, Digg, Rackspace, Mahalo and Reddit) CouchDB (document, written in Erlang, used by Engine Yard and BBC) Dynomite (key-value, written in C++, used by Powerset) HBase (key-value, written in Java, used by Bing) Hypertable (tabular, written in C++, used by Baidu) Kai (key-value, written in Erlang) MemcacheDB (key-value, written in C, used by Reddit) MongoDB (document, written in C++, used by Sourceforge, Github, Electronic Arts and NY Times) Neo4j (graph, written in Java, used by Swedish Universities) Project Voldemort (key-value, written in Java, used by LinkedIn) Redis (key-value, written in C, used by Engine Yard, Github and Craigslist) Riak (key-value, written in Erlang, used by Comcast and Mochi Media) Ringo (key-value, written in Erlang, used by Nokia) Scalaris (key-value, written in Erlang, used by OnScale) ThruDB (document, written in C++, used by JunkDepot.com) Tokyo Cabinet/Tokyo Tyrant (key-value, written in C, used by Mixi.jp (Japanese social networking site)) I'd like to know about specific problems you - the SO reader - have solved using data stores and what NoSQL data store you used. Questions: What scalability problems have you used NoSQL data stores to solve? What NoSQL data store did you use? What database did you use before switching to a NoSQL data store? I'm looking for first-hand experiences, so please do not answer unless you have that.

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• Algorithm for finding similar users through a join table

  - by Gdeglin

  I have an application where users can select a variety of interests from around 300 possible interests. Each selected interest is stored in a join table containing the columns user_id and interest_id. Typical users select around 50 interests out of the 300. I would like to build a system where users can find the top 20 users that have the most interests in common with them. Right now I am able to accomplish this using the following query: SELECT i2.user_id, count(i2.interest_id) AS count FROM interests_users as i1, interests_users as i2 WHERE i1.interest_id = i2.interest_id AND i1.user_id = 35 GROUP BY i2.user_id ORDER BY count DESC LIMIT 20; However, this query takes approximately 500 milliseconds to execute with 10,000 users and 500,000 rows in the join table. All indexes and database configuration settings have been tuned to the best of my ability. I have also tried avoiding the use of joins altogether using the following query: select user_id,count(interest_id) count from interests_users where interest_id in (13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,508) group by user_id order by count desc limit 20; But this one is even slower (~800 milliseconds). How could I best lower the time that I can gather this kind of data to below 100 milliseconds? I have considered putting this data into a graph database like Neo4j, but I am not sure if that is the easiest solution or if it would even be faster than what I am currently doing.

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• Implementing a scalable and high-performing web app

  - by Christopher McCann

  I have asked a few questions on here before about various things relating to this but this is more of a consolidation question as I would like to check I have got the gist of everything. I am in the middle of developing a social media web app and although I have a lot of experience coding in Java and in PHP I am trying things a bit different this time. I have modularised each component of the application. So for example one component of the application allows users to private message each other and I have split this off into its own private messaging service. I have also created a user data service the purpose of which is to return data about the user for example their name, address, age etc etc from the database. Their is also another service, the friends service, which will work off the neo4j database to create a social graph. My reason for doing all this is to allow me up to update seperate modules when I need to - so while they mostly all run off MySQL right now I could move one to Cassandra later if I thought it approriate. The actual code of the web app is really just used for the final construction. The modules behind it dont really follow any strict REST or SOAP protocol. Basically each method on our API is turned into a PHP procedural script. This then may make calls to other back-end code which tends to be OO. The web app makes CURL requests to these pages and POSTs data to them or GETs data from them. These pages then return JSON where data is required. I'm still a little mixed up about how I actually identify which user is logged in at that moment. Do I just use sessions for that? Like if we called the get-messages.php script which equates to the getMessages() method for that user - returning all the private messages for that user - how would the back-end code know which user it is as posting the users ID to the script would not be secure. Anyone could do that and get all the messages. So I thought I would use sessions for it. Am I correct on this? Can anyone spot any other problems with what I am doing here? Thanks

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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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