Search Results

Search found 1120 results on 45 pages for 'simplest'.

Page 42/45 | < Previous Page | 38 39 40 41 42 43 44 45  | Next Page >

  • Week in Geek: 4chan Falls Victim to DDoS Attack Edition

    - by Asian Angel
    This week we learned how to tweak the low battery action on a Windows 7 laptop, access an eBook collection anywhere in the world, “extend iPad battery life, batch resize photos, & sync massive music collections”, went on a reign of destruction with Snow Crusher, and had fun decorating our desktops with abstract icon collections. Photo by pasukaru76. Random Geek Links We have included extra news article goodness to help you catch up on any developments that you may have missed during the holiday break this past week. Note: The three 27C3 articles listed here represent three different presentations at the 27th Chaos Communication Congress hacker conference. 4chan victim of DDoS as FBI investigates role in PayPal attack Users of 4chan may have gotten a taste of their own medicine after the site was knocked offline by a DDoS attack from an unknown origin early Thursday morning. Report: FBI seizes server in probe of WikiLeaks attacks The FBI has seized a server in Texas as part of its hunt for the groups behind the pro-WikiLeaks denial-of-service attacks launched in December against PayPal, Visa, MasterCard, and others. Mozilla exposes older user-account database Mozilla has disabled 44,000 older user accounts for its Firefox add-ons site after a security researcher found part of a database of the account information on a publicly available server. Data breach affects 4.9 million Honda customers Japanese automaker Honda has put some 2.2 million customers in the United States on a security breach alert after a database containing information on the owners and their cars was hacked. Chinese Trojan discovered in Android games An Android-based Trojan called “Geinimi” has been discovered in the wild and the Trojan is capable of sending personal information to remote servers and exhibits botnet-like behavior. 27C3 presentation claims many mobiles vulnerable to SMS attacks According to security experts, an ‘SMS of death’ threatens to disable many current Sony Ericsson, Samsung, Motorola, Micromax and LG mobiles. 27C3: GSM cell phones even easier to tap Security researchers have demonstrated how open source software on a number of revamped, entry-level cell phones can decrypt and record mobile phone calls in the GSM network. 27C3: danger lurks in PDF documents Security researcher Julia Wolf has pointed out numerous, previously hardly known, security problems in connection with Adobe’s PDF standard. Critical update for WordPress A critical update has been made available for WordPress in the form of version 3.0.4. The update fixes a security bug in WordPress’s KSES library. McAfee Labs Predicts Geolocation, Mobile Devices and Apple Will Top the List of Targets for Emerging Threats in 2011 The list comprises 2010’s most buzzed about platforms and services, including Google’s Android, Apple’s iPhone, foursquare, Google TV and the Mac OS X platform, which are all expected to become major targets for cybercriminals. McAfee Labs also predicts that politically motivated attacks will be on the rise. Windows Phone 7 piracy materializes with FreeMarketplace A proof-of-concept application, FreeMarketplace, that allows any Windows Phone 7 application to be downloaded and installed free of charge has been developed. Empty email accounts, and some bad buzz for Hotmail In the past few days, a number of Hotmail users have been complaining about a rather disconcerting issue: their Hotmail accounts, some up to 10 years old, appear completely empty.  No emails, no folders, nothing, just what appears to be a new account. Reports: Nintendo warns of 3DS risk for kids Nintendo has reportedly issued a warning that the 3DS, its eagerly awaited glasses-free 3D portable gaming device, should not be used by children under 6 when the gadget is in 3D-viewing mode. Google eyes ‘cloaking’ as next antispam target Google plans to take a closer look at the practice of “cloaking,” or presenting one look to a Googlebot crawling one’s site while presenting another look to users. Facebook, Twitter stock trading drawing SEC eye? The high degree of investor interest in shares of hot Silicon Valley companies that aren’t yet publicly traded–like Facebook, Twitter, LinkedIn, and Zynga–may be leading to scrutiny from the U.S. Securities and Exchange Commission (SEC). Random TinyHacker Links Photo by jcraveiro. Exciting Software Set for Release in 2011 A few bloggers from great websites such as How-To Geek, Guiding Tech and 7 Tutorials took the time to sit down and talk about their software wishes for 2011. Take the time to read it and share… Wikileaks Infopr0n An infographic detailing the quest to plug WikiLeaks. The New York Times Guide to Mobile Apps A growing collection of all mobile app coverage by the New York Times as well as lists of favorite apps from Times writers. 7,000,000,000 (Video) A fascinating look at the world’s population via National Geographic Magazine. Super User Questions Check out the great answers to these hot questions from Super User. How to use a Personal computer as a Linux web server for development purposes? How to link processing power of old computers together? Free virtualization tool for testing suspicious files? Why do some actions not work with Remote Desktop? What is the simplest way to send a large batch of pictures to a distant friend or colleague? How-To Geek Weekly Article Recap Had a busy week and need to get caught up on your HTG reading? Then sit back and relax while enjoying these hot posts full of how-to roundup goodness. The 50 Best How-To Geek Windows Articles of 2010 The 20 Best How-To Geek Explainer Topics for 2010 The 20 Best How-To Geek Linux Articles of 2010 How to Search Just the Site You’re Viewing Using Google Search Ask the Readers: Backing Your Files Up – Local Storage versus the Cloud One Year Ago on How-To Geek Need more how-to geekiness for your weekend? Then look through this great batch of articles from one year ago that focus on dual-booting and O.S. installation goodness. Dual Boot Your Pre-Installed Windows 7 Computer with Vista Dual Boot Your Pre-Installed Windows 7 Computer with XP How To Setup a USB Flash Drive to Install Windows 7 Dual Boot Your Pre-Installed Windows 7 Computer with Ubuntu Easily Install Ubuntu Linux with Windows Using the Wubi Installer The Geek Note We hope that you and your families have had a terrific holiday break as everyone prepares to return to work and school this week. Remember to keep those great tips coming in to us at [email protected]! Photo by pjbeardsley. 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

    Read the article

  • Simplify your Ajax code by using jQuery Global Ajax Handlers and ajaxSetup low-level interface

    - by hajan
    Creating web applications with consistent layout and user interface is very important for your users. In several ASP.NET projects I’ve completed lately, I’ve been using a lot jQuery and jQuery Ajax to achieve rich user experience and seamless interaction between the client and the server. In almost all of them, I took advantage of the nice jQuery global ajax handlers and jQuery ajax functions. Let’s say you build web application which mainly interacts using Ajax post and get to accomplish various operations. As you may already know, you can easily perform Ajax operations using jQuery Ajax low-level method or jQuery $.get, $.post, etc. Simple get example: $.get("/Home/GetData", function (d) { alert(d); }); As you can see, this is the simplest possible way to make Ajax call. What it does in behind is constructing low-level Ajax call by specifying all necessary information for the request, filling with default information set for the required properties such as data type, content type, etc... If you want to have some more control over what is happening with your Ajax Request, you can easily take advantage of the global ajax handlers. In order to register global ajax handlers, jQuery API provides you set of global Ajax methods. You can find all the methods in the following link http://api.jquery.com/category/ajax/global-ajax-event-handlers/, and these are: ajaxComplete ajaxError ajaxSend ajaxStart ajaxStop ajaxSuccess And the low-level ajax interfaces http://api.jquery.com/category/ajax/low-level-interface/: ajax ajaxPrefilter ajaxSetup For global settings, I usually use ajaxSetup combining it with the ajax event handlers. $.ajaxSetup is very good to help you set default values that you will use in all of your future Ajax Requests, so that you won’t need to repeat the same properties all the time unless you want to override the default settings. Mainly, I am using global ajaxSetup function similarly to the following way: $.ajaxSetup({ cache: false, error: function (x, e) { if (x.status == 550) alert("550 Error Message"); else if (x.status == "403") alert("403. Not Authorized"); else if (x.status == "500") alert("500. Internal Server Error"); else alert("Error..."); }, success: function (x) { //do something global on success... } }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now, you can make ajax call using low-level $.ajax interface and you don’t need to worry about specifying any of the properties we’ve set in the $.ajaxSetup function. So, you can create your own ways to handle various situations when your Ajax requests are occurring. Sometimes, some of your Ajax Requests may take much longer than expected… So, in order to make user friendly UI that will show some progress bar or animated image that something is happening in behind, you can combine ajaxStart and ajaxStop methods to do the same. First of all, add one <div id=”loading” style=”display:none;”> <img src="@Url.Content("~/Content/images/ajax-loader.gif")" alt="Ajax Loader" /></div> anywhere on your Master Layout / Master page (you can download nice ajax loading images from http://ajaxload.info/). Then, add the following two handlers: $(document).ajaxStart(function () { $("#loading").attr("style", "position:absolute; z-index: 1000; top: 0px; "+ "left:0px; text-align: center; display:none; background-color: #ddd; "+ "height: 100%; width: 100%; /* These three lines are for transparency "+ "in all browsers. */-ms-filter:\"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)\";"+ " filter: alpha(opacity=50); opacity:.5;"); $("#loading img").attr("style", "position:relative; top:40%; z-index:5;"); $("#loading").show(); }); $(document).ajaxStop(function () { $("#loading").removeAttr("style"); $("#loading img").removeAttr("style"); $("#loading").hide(); }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Note: While you can reorganize the style in a more reusable way, since these are global Ajax Start/Stop, it is very possible that you won’t use the same style in other places. With this way, you will see that now for any ajax request in your web site or application, you will have the loading image appearing providing better user experience. What I’ve shown is several useful examples on how to simplify your Ajax code by using Global Ajax Handlers and the low-level AjaxSetup function. Of course, you can do a lot more with the other methods as well. Hope this was helpful. Regards, Hajan

    Read the article

  • How to use Bonjour?

    - by Roman
    First, what exactly Bonjour does (pleas read my guesses written bellow)? Here I found out that Bonjour enables automatic discovery of computers, devices, and services on IP networks. But I thought that it not only "discovers devices on IP network" it also creates an IP network by assigning IP addresses to devices where Bonjour is running. Am I right? And I still miss the essence. Does it work in the following way? First I connect devices (for example laptops) physically so that they potentially can communicate with each other. Then, let say, on some laptops I have Bonjour running and then, as a consequence, these laptops assign IP addresses to them self in automatic way. So, laptops (where Bonjour is running) build an IP network. Does it work in this way? Or may be a computer running Bonjour is not considered as a service and it does not broadcast itself just because Bonjour is running on this computer. I mean that the applications running on the computers need to use Bonjour to broadcast themself. So, it is applications that broadcast themself (not computers) and it is not done automatically (application needs to broadcast themself explicitly). Is it right? How exactly my application can broadcast itself? Can I use command line to register an service (so that all applications using Bonjour knows that a new service appeared)? Further, I would like to have an application which use the IP network created by Bonjour. For that my application needs to know which devices/services are present in the network. In more details, my application needs to have a list of services. Each service in the list should have a name, the IP address where it is running and the port which is used by the application. Can Bonjour provide this information in some way? If it is the case, how exactly it works. How my program can get this information from Bonjour? Can my program read some file created by Bonjour and containing the above mentioned information? Can I use some commands in command line to retrieve this information? I have a special interest in accessing the information about services from files, environment variables or commands in command line. These options seems to me to be the simplest! Since in these case I do not need to use any additional libraries to communicate with Bonjour from a particular programming language. P.S. Pleas ask questions if something is not clear in my question. I will try to formulate my question in a more clear way. P.P.S. I use Windows 7. ADDED: I plan to write my applications in PHP. Every computer should run a Apache web server. And I want to use Bonjour to help computer discover each other (computers are working in a local network).

    Read the article

  • Multi-tenant ASP.NET MVC - Views

    - by zowens
    Part I – Introduction Part II – Foundation Part III – Controllers   So far we have covered the basic premise of tenants and how they will be delegated. Now comes a big issue with multi-tenancy, the views. In some applications, you will not have to override views for each tenant. However, one of my requirements is to add extra views (and controller actions) along with overriding views from the core structure. This presents a bit of a problem in locating views for each tenant request. I have chosen quite an opinionated approach at the present but will coming back to the “views” issue in a later post. What’s the deal? The path I’ve chosen is to use precompiled Spark views. I really love Spark View Engine and was planning on using it in my project anyways. However, I ran across a really neat aspect of the source when I was having a look under the hood. There’s an easy way to hook in embedded views from your project. There are solutions that provide this, but they implement a special Virtual Path Provider. While I think this is a great solution, I would rather just have Spark take care of the view resolution. The magic actually happens during the compilation of the views into a bin-deployable DLL. After the views are compiled, the are simply pulled out of the views DLL. Each tenant has its own views DLL that just has “.Views” appended after the assembly name as a convention. The list of reasons for this approach are quite long. The primary motivation is performance. I’ve had quite a few performance issues in the past and I would like to increase my application’s performance in any way that I can. My customized build of Spark removes insignificant whitespace from the HTML output so I can some some bandwidth and load time without having to deal with whitespace removal at runtime.   How to setup Tenants for the Host In the source, I’ve provided a single tenant as a sample (Sample1). This will serve as a template for subsequent tenants in your application. The first step is to add a “PostBuildStep” installer into the project. I’ve defined one in the source that will eventually change as we focus more on the construction of dependency containers. The next step is to tell the project to run the installer and copy the DLL output to a folder in the host that will pick up as a tenant. Here’s the code that will achieve it (this belongs in Post-build event command line field in the Build Events tab of settings) %systemroot%\Microsoft.NET\Framework\v4.0.30319\installutil "$(TargetPath)" copy /Y "$(TargetDir)$(TargetName)*.dll" "$(SolutionDir)Web\Tenants\" copy /Y "$(TargetDir)$(TargetName)*.pdb" "$(SolutionDir)Web\Tenants\" The DLLs with a name starting with the target assembly name will be copied to the “Tenants” folder in the web project. This means something like MultiTenancy.Tenants.Sample1.dll and MultiTenancy.Tenants.Sample1.Views.dll will both be copied along with the debug symbols. This is probably the simplest way to go about this, but it is a tad inflexible. For example, what if you have dependencies? The preferred method would probably be to use IL Merge to merge your dependencies with your target DLL. This would have to be added in the build events. Another way to achieve that would be to simply bypass Visual Studio events and use MSBuild.   I also got a question about how I was setting up the controller factory. Here’s the basics on how I’m setting up tenants inside the host (Global.asax) protected void Application_Start() { RegisterRoutes(RouteTable.Routes); // create a container just to pull in tenants var topContainer = new Container(); topContainer.Configure(config => { config.Scan(scanner => { scanner.AssembliesFromPath(Path.Combine(Server.MapPath("~/"), "Tenants")); scanner.AddAllTypesOf<IApplicationTenant>(); }); }); // create selectors var tenantSelector = new DefaultTenantSelector(topContainer.GetAllInstances<IApplicationTenant>()); var containerSelector = new TenantContainerResolver(tenantSelector); // clear view engines, we don't want anything other than spark ViewEngines.Engines.Clear(); // set view engine ViewEngines.Engines.Add(new TenantViewEngine(tenantSelector)); // set controller factory ControllerBuilder.Current.SetControllerFactory(new ContainerControllerFactory(containerSelector)); } The code to setup the tenants isn’t actually that hard. I’m utilizing assembly scanners in StructureMap as a simple way to pull in DLLs that are not in the AppDomain. Remember that there is a dependency on the host in the tenants and a tenant cannot simply be referenced by a host because of circular dependencies.   Tenant View Engine TenantViewEngine is a simple delegator to the tenant’s specified view engine. You might have noticed that a tenant has to define a view engine. public interface IApplicationTenant { .... IViewEngine ViewEngine { get; } } The trick comes in specifying the view engine on the tenant side. Here’s some of the code that will pull views from the DLL. protected virtual IViewEngine DetermineViewEngine() { var factory = new SparkViewFactory(); var file = GetType().Assembly.CodeBase.Without("file:///").Replace(".dll", ".Views.dll").Replace('/', '\\'); var assembly = Assembly.LoadFile(file); factory.Engine.LoadBatchCompilation(assembly); return factory; } This code resides in an abstract Tenant where the fields are setup in the constructor. This method (inside the abstract class) will load the Views assembly and load the compilation into Spark’s “Descriptors” that will be used to determine views. There is some trickery on determining the file location… but it works just fine.   Up Next There’s just a few big things left such as StructureMap configuring controllers with a convention instead of specifying types directly with container construction and content resolution. I will also try to find a way to use the Web Forms View Engine in a multi-tenant way we achieved with the Spark View Engine without using a virtual path provider. I will probably not use the Web Forms View Engine personally, but I’m sure some people would prefer using WebForms because of the maturity of the engine. As always, I love to take questions by email or on twitter. Suggestions are always welcome as well! (Oh, and here’s another link to the source code).

    Read the article

  • Windows Azure Evolution &ndash; Welcome to VS2012

    - by Shaun
    When the Microsoft released the first preview version of Windows 8 and Visual Studio, many people in the community were asking if the windows azure tool is available to it. The answer was “NO”. Microsoft promised that the windows azure tool will only support the Visual Studio 2010 but when the 2012 was final released, windows azure tool should be work. But now alone with the new windows azure platform was published we got the latest Windows Azure SDK 1.7, which is compatible to the Visual Studio 2012 RC.   You can retrieve the latest version of the Windows Azure SDK through Web Platform Installer, which I think it’s the easiest and simplest way to download and install, since besides the SDK itself it also needs some other components. To download the latest windows azure SDK from Web Platform Installer, just go to the windows azure website and clicked the Develop, .NET and click the blue “install” button. Then you need to select which version of Visual Studio you want to use, Visual Studio 2010 or Visual Studio 2012 RC. After selected the current version you will download an EXE file. This file will lead you to install the Web Platform Installer 4.0 (if you haven’t installed) and the latest windows azure SDK. You can see the version name is June 2012, 1.7. Finally the WebPI will detect the dependent components you need to download and begin to install. But if you want to challenge yourself you can download the components and install them manually. The standalone installations are listed in this page with the instruction on how to install them with necessary pre-requirements.   Once you finished the installation you can open the Visual Studio 2012 RC and as usual, it need to be run as administrator. If you clicked the New Project link from the start page, navigated to Cloud category you will find that there no project template available. Is there anything wrong? So, if you changed the target framework from the default .NET 4.5 to .NET 4 you will see the azure project template. This is because, currently the windows azure instance does not support .NET 4.5. After clicked OK you will see the role creation window, which is similar as what you have seen before. But there are some new role templates in this SDK. Firstly you will have ASP.NET MVC 4 web role available, which means you can create ASP.NET MVC 4 applications for internet, intranet, mobile and WebAPI on the cloud. Then there are two new worker role templates, “Cache Worker Role” and “Worker Role with Service Bus Queue”. “Worker Role with Service Bus Queue” is a worker role which had added necessary references to access the Windows Azure Service Bus Queue. It also have some basic sample code in the worker role class which could read messages from the queue when started. The “Cache Worker Role” is a worker role which has the in-memory distributed cache feature enabled by default. This feature is different than the Windows Azure Caching. It allows the role instance to use its memory as a in-memory distributed cache clusters. By using this feature you can have one or more worker roles as some dedicate cache clusters. Alternatively, you can make part of your web role and worker role’s memory as the cache clusters as well. Let’s just create an ASP.NET MVC 4 Web Role, and click F5 to run it under the local emulator. If you have been working with azure for a while you should know that I need to setup the local storage emulator before running locally if it’s a fresh azure SDK installation. But in this version when we started our azure project the Visual Studio will check if the storage emulator had been initialized. If not, it will run the initializer automatically. And as you can see, in this version the storage emulator relies on the SQL Server 2012 Local DB feature. It will create the emulator database and tables in the default local database. You can set the storage emulator to use a standard SQL Server default instance by using the command “dsinit /instance:.”. The “dsinit” tool now is located at %PROGRAM FILES%\Microsoft SDKs\Windows Azure\Emulator\devstore After the Visual Studio complied and deployed the package our website should be shown in the browser. This is the MVC 4 Web Role home page on my Windows 8 machine in IE10. Another thing you might notice is that, in this version the compute emulator utilizes IIS Express to host the web roles instead of the full IIS. You can add breakpoint in the code and debug, and you can use the local storage emulator to test your code for accessing the storage service. All of them are same as what your are doing now on SDK 1.6. You can switch to use IIS to run your web role in local emulator. Just open the windows azure porject property windows, in the Web page select “Use IIS Web Server”. For more information about this please have a look on Nuno’s blog post. In the role property page in Visual Studio there’s no massive changes. You can configure your role settings such as the endpoints, certificates and local storage, etc.. One thing was added is the Caching tab. Here you can specify enable the caching feature or not, and how much memory you want to use as the cache cluster. I will introduce more details about it in the future posts. The publish and package feature are also no change. You can publish your project to azure directly through Visual Studio 2012, while you can create the package and upload manually. Below is the SDK version of my deployment which is 1.7.30602.1703 in the developer portal.   Summary In this post I introduced about the new Windows Azure SDK 1.7 especially on how it works on the latest Visual Studio 2012 RC. There’s no significant changes in the visual studio tool in this version but some small enhancement such as ASP.NET MVC 4, Cache Worker Role, using SQL 2012 Local DB and IIS Express, etc..   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

    Read the article

  • CodePlex Daily Summary for Sunday, April 18, 2010

    CodePlex Daily Summary for Sunday, April 18, 2010New ProjectsBare Bones Email Trace Listener: Bare Bones Email Trace Listener is about the simplest email trace listener you can have. No bells, no whistles, and no good if you need authenticat...Cartellino: Scopo del progetto è la realizzazione di un software in grado di rilevare i dati dai rilevatori 3Tec (www.3tec.it) e stampare i cartellini presenza...Castle Windsor app.config Properties: The Castle Windsor app.config Properties library makes it possible for users of Castle Windsor to reference appSettings values in Windsor's XML pro...DeskD: This is a simple desktop dictionary application(something like WordWeb) created in Java using Netbeans IDE. Since i am new to codeplex all updates ...FunPokerMakerOnline: It is a play of poker online with a game editor. It is done with .net 4 and WPF and SOAP or WCF. KLOCS Team GIN Project: This is a Master's Degree program group project. It may have academic interest, but won't be maintained after June 2010KNN: This is KNN projectProject Santa: Program to organize teams using mysql databases and c# in a clean and robust task and group system. For more information see my blog post at http:/...ProjetoIntegradoJuridico: Sistema Integrado de Acompanhamento JurídicoRSSR for Windows Phone 7: This is a simple RSS reader application, the project aims to show people that it is easy to build application for windows phones. The applicatio...Simple Rcon: Simple Rcon is a simple lightweight rcon client for HL1/HL2 Servers. It is developed in C# and WPFTAB METHOD SQL Create a data dictionary from your Transact SQL code: TABMETHODSQL makes it easier for data/information workers to document their work. Create a data governance solution that maps sql data process, inc...TM BF Tournament: WPF software to manage Trackmania tournament with Battle France RulesviBlog: visinia plugin, this plugin is used to add blogging facility in visinia cmsviNews: visinia plugin, this plugin can be used to create a news portal like cnn.com nytimeVolumeMaster: VolumeMaster is an On Screen Display (OSD) that gets activated whenever the volume changes. It's written in WPF and uses Vista Core Audio API by Ra...WiiCIS.NET: This is a managed port of WiiCIS, which is a Nintendo Wiimote library originally created by TheOboeNerd and posted on Sourceforge.New ReleasesCastle Windsor app.config Properties: Version 1.0: Initial release.Code for Rapid C# Windows Development eBook: Enumerable Debugger Visualizer Version 1.1: Second release of the Enumerable Debugger Visualizer. There are more classes registered and it is more robust. The list of classes I have register...Convection Game Engine (Basic Edition): Convection Basic (40223): Compiled version of Convection Basic change set 40223.CycleMania Starter Kit EAP - ASP.NET 4 Problem - Design - Solution: Cyclemania 0.08.59: See Source Code tab for recent change history.DbEntry.Net (Lephone Framework): DbEntry.Net 3.9: DbEntry.Net is a lightweight Object Relational Mapping (ORM) database access compnent for .Net 3.5. It has clearly and easily programing interface ...Hash Calculator: HashCalculator 2.0: Upgraded to .NET Framework 4.0 Added support to calculate CRC32 hash function Added "Cancel" button in the Windows 7 taskbar thumbnailHKGolden Express: HKGoldenExpress (Build 201004172120): New features: Added jump links at top of page of message. Bug fix: Fixed page count bug. Improvements: HKGolden Express now uses DocumentBuild...HTML Ruby: 6.21.4: Styles added to override those on some sites for better rendering of ruby Fix regression on complex ruby annotation rendering Better spacingHTML Ruby: 6.21.5: Removed debug code in preference handling Status bar indicator now resets for each action Replace ruby in place without using document fragment...IceChat: IceChat 2009 Alpha 12.4 EXE Update: This is simply an update to the main IceChat program files and DLL. Simpply overwrite the ones in the place where IceChat 2009 is installed.IceChat: IceChat 2009 Alpha 12.4 Full Install: Build Alpha 12.4 - April 17 2010 Added IceChatScript.dll , needs to be added in same folder with EXE and IPluginIceChat.dll Added Self Notice in ...PokeIn Comet Ajax Library: PokeIn Library v05 x64: With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release candidate of PokeIn. Cheers!PokeIn Comet Ajax Library: PokeIn Library v05 x86: PokeIn Library version 0.5 (x86) With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release c...Project Santa: Project Santa V1.0: The first initial release of my project manager program, for more information see http://coderplex.blogspot.com/2010/04/project-manager-using-mysq...Salient: TestingWithVSDevServer v1: Using code from Salient, I have assembled a few strategies for programmatic contol of the Visual Studio Development Server (WebDev.WebServer.exe). ...SharePoint Navigation Menu: spNavigationMenu 1.1: Changed the CAML query so it will order by Link Order, then Title. Added the ability to override the On Hover event on the parent menu to use On ...Simple Rcon: Simple Rcon Version 1: Version 1TAB METHOD SQL Create a data dictionary from your Transact SQL code: RELEASE 1: TESTING THE RELEASE SYSTEMTribe.Cache: Tribe.Cache Beta 0.1: Beta release of Tribe.Cache - Now with cache expiration serviceviBlog: viBlog_beta: visinia plugin to add blogging facility in visinia cmsviNews: viNews_beta: visinia plugin.visinia: visinia_beta2: visinia beta 2 released with many new feature.Visual Studio DSite: Visual C++ 2008 Login Form: A simple login form made in visual c 2008. Source code only.WiiCIS.NET: WiiCIS.NET v0.11: 0.11 Removed an unnecessary function from the Wiimote class, and improved the demo. You will need the latest version of SlimDX to compile the sourc...WinControls TreeListView: TreeListView 1.5.1: -fixes issue #5837 -Preliminary feature #5874WoW Character Viewer: Viewer Setup: Finally, I've brought out the next setup of WoW Viewer. Most loose ends have been tied up. Loading and Saving of character files has been fixed.Most Popular ProjectsRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseMicrosoft SQL Server Community & Samplespatterns & practices – Enterprise LibraryPHPExcelFacebook Developer ToolkitBlogEngine.NETMvcContrib: a Codeplex Foundation projectIronPythonMost Active ProjectsRawrpatterns & practices – Enterprise LibraryIndustrial DashboardFarseer Physics EnginejQuery Library for SharePoint Web ServicesIonics Isapi Rewrite FilterGMap.NET - Great Maps for Windows Forms & PresentationProxi [Proxy Interface]BlogEngine.NETCaliburn: An Application Framework for WPF and Silverlight

    Read the article

  • Complex type support in process flow &ndash; XMLTYPE

    - by shawn
        Before OWB 11.2 release, there are only 5 simple data types supported in process flow: DATE, BOOLEAN, INTEGER, FLOAT and STRING. A new complex data type – XMLTYPE is added in 11.2, in order to support complex data being passed between the process flow activities. In this article we will give a simple example to illustrate the usage of the new type and some related editors.     Suppose there is a bookstore that uses XML format orders as shown below (we use the simplest form for the illustration purpose), then we can create a process flow to handle the order, take the order as the input, then extract necessary information, and generate a confirmation email to the customer automatically. <order id=’0001’>     <customer>         <name>Tom</name>         <email>[email protected]</email>     </customer>     <book id=’Java_001’>         <quantity>3</quantity>     </book> </order>     Considering a simple user case here: we use an input parameter/variable with XMLTYPE to hold the XML content of the order; then we can use an Assign activity to retrieve the email info from the order; after that, we can create an email activity to send the email (Other activities might be added in practical case, but will not be described here). 1) Set XML content value     For testing purpose, we will create a variable to hold the sample order, and then this will be used among the process flow activities. When the variable is of XMLTYPE and the “Literal” value is set the true, the advance editor will be enabled.     Click the “Advance Editor” shown as above, a simple xml editor will popup. The editor has basic features like syntax highlight and check as shown below:     We can also do the basic validation or validation against schema with the editor by selecting the normalized schema. With this, it will be easier to provide the value for XMLTYPE variables. 2) Extract information from XML content     After setting the value, we need to extract the email information with the Assign activity. In process flow, an enhanced expression builder is used to help users construct the XPath for extracting values from XML content. When the variable’s literal value is set the false, the advance editor is enabled.     Click the button, the advance editor will popup, as shown below:     The editor is based on the expression builder (which is often used in mapping etc), an XPath lib panel is appended which provides some help information on how to write the XPath. The expression used here is: “XMLTYPE.EXTRACT(XML_ORDER,'/order/customer/email/text()').getStringVal()”, which uses ‘/order/customer/email/text()’ as the XPath to extract the email info from the XML document.     A variable called “EMAIL_ADDR” is created with String data type to hold the value extracted.     Then we bind the “VARIABLE” parameter of Assign activity to “EMAIL_ADDR” variable, which means the value of the “EMAIL_ADDR” activity will be set to the result of the “VALUE” parameter of Assign activity. 3) Use the extracted information in Email activity     We bind the “TO_ADDRESS” parameter of the email activity to the “EMAIL_ADDR” variable created in above step.     We can also extract other information from the xml order directly through the expression, for example, we can set the “MESSAGE_BODY” with value “'Dear '||XMLTYPE.EXTRACT(XML_ORDER,'/order/customer/name/text()').getStringVal()||chr(13)||chr(10)||'   You have ordered '||XMLTYPE.EXTRACT(XML_ORDER,'/order/book/quantity/text()').getStringVal()||' '||XMLTYPE.EXTRACT(XML_ORDER,'/order/book/@id').getStringVal()”. This expression will extract the customer name, the quantity and the book id from the order to compose the message body.     To make the email activity work, we need provide some other necessary information, Such as “SMTP_SERVER” (which is the SMTP server used to send the emails, like “mail.bookstore.com”. The default PORT number is set to 25. You need to change the value accordingly), “FROM_ADDRESS” and “SUBJECT”. Then the process flow is ready to go.     After deploying the process flow package, we can simply run the process flow to check if the result is as expected (An email will be sent to the specified email address with proper subject and message body).     Note: In oracle 11g, there is an enhanced security feature - ACL (Access Control List), which restrict the network access within db, so we need to edit the list to allow UTL_SMTP work if you are using oracle 11g. Refer to chapter “Access Control Lists for UTL_TCP/HTTP/SMTP” and “Managing Fine-Grained Access to External Network Services” for more details.       In previous releases, XMLTYPE already exists in other OWB objects, like mapping/transformation etc. When the mapping/transformation is dragged into a process flow, the parameters with XMLTYPE are mapped to STRING. Now with the XMLTYPE support in process flow, the XMLTYPE will map to XMLTYPE in a more natural way, and we can leverage the new data type for the design.

    Read the article

  • Database continuous integration step by step

    - by David Atkinson
    This post will describe how to set up basic database continuous integration using TeamCity to initiate the build process, SQL Source Control to put your database under source control, and the SQL Compare command line to keep a test database up to date. In my example I will be using Subversion as my source control repository. If you wish to follow my steps verbatim, please make sure you have TortoiseSVN, SQL Compare and SQL Source Control installed. Downloading and Installing TeamCity TeamCity (http://www.jetbrains.com/teamcity/index.html) is free for up to three agents, so it a great no-risk tool you can use to experiment with. 1. Download the latest version from the JetBrains website. For some reason the TeamCity executable didn't download properly for me, stalling frustratingly at 99%, so I tried again with the zip file download option (see screenshot below), which worked flawlessly. 2. Run the installer using the defaults. This results in a set-up with the server component and agent installed on the same machine, which is ideal for getting started with ease. 3. Check that the build agent is pointing to the server correctly. This has caught me out a few times before. This setting is in C:\TeamCity\buildAgent\conf\buildAgent.properties and for my installation is serverUrl=http\://localhost\:80 . If you need to change this value, if for example you've had to install the Server console to a different port number, the TeamCity Build Agent Service will need to be restarted for the change to take effect. 4. Open the TeamCity admin console on http://localhost , and specify your own designated username and password at first startup. Putting your database in source control using SQL Source Control 5. Assuming you've got SQL Source Control installed, select a development database in the SQL Server Management Studio Object Explorer and select Link Database to Source Control. 6. For the Link step you can either create your own empty folder in source control, or you can select Just Evaluating, which just creates a local subversion repository for you behind the scenes. 7. Once linked, note that your database turns green in the Object Explorer. Visit the Commit tab to do an initial commit of your database objects by typing in an appropriate comment and clicking Commit. 8. There is a hidden feature in SQL Source Control that opens up TortoiseSVN (provided it is installed) pointing to the linked repository. Keep Shift depressed and right click on the text to the right of 'Linked to', in the example below, it's the red Evaluation Repository text. Select Open TortoiseSVN Repo Browser. This screen should give you an idea of how SQL Source Control manages the object files behind the scenes. Back in the TeamCity admin console, we'll now create a new project to monitor the above repository location and to trigger a 'build' each time the repository changes. 9. In TeamCity Adminstration, select Create Project and give it a name, such as "My first database CI", and click Create. 10. Click on Create Build Configuration, and name it something like "Integration build". 11. Click VCS settings and then Create And Attach new VCS root. This is where you will tell TeamCity about the repository it should monitor. 12. In my case since I'm using the Just Evaluating option in SQL Source Control, I should select Subversion. 13. In the URL field paste your repository location. In my case this is file:///C:/Users/David.Atkinson/AppData/Local/Red Gate/SQL Source Control 3/EvaluationRepositories/WidgetDevelopment/WidgetDevelopment 14. Click on Test Connection to ensure that you can communicate with your source control system. Click Save. 15. Click Add Build Step, and Runner Type: Command Line. Should you be familiar with the other runner types, such as NAnt, MSBuild or Powershell, you can opt for these, but for the same of keeping it simple I will pick the simplest option. 16. If you have installed SQL Compare in the default location, set the Command Executable field to: C:\Program Files (x86)\Red Gate\SQL Compare 10\sqlcompare.exe 17. Flip back to SSMS briefly and add a new database to your server. This will be the database used for continuous integration testing. 18. Set the command parameters according to your server and the name of the database you have created. In my case I created database RedGateCI on server .\sql2008r2 /scripts1:. /server2:.\sql2008r2 /db2:RedGateCI /sync /verbose Note that if you pick a server instance that isn't on your local machine, you'll need the TCP/IP protocol enabled in SQL Server Configuration Manager otherwise the SQL Compare command line will not be able to connect. 19. Save and select Build Triggering / Add New Trigger / VCS Trigger. This is where you tell TeamCity when it should initiate a build. Click Save. 20. Now return to SQL Server Management Studio and make a schema change (eg add a new object) to your linked development database. A blue indicator will appear in the Object Explorer. Commit this change, typing in an appropriate check-in comment. All being good, within 60 seconds (a TeamCity default that can be changed) a build will be triggered. 21. Click on Projects in TeamCity to get back to the overview screen: The build log will show you the console output, which is useful for troubleshooting any issues: That's it! You now have continuous integration on your database. In future posts I'll cover how you can generate and test the database creation script, the database upgrade script, and run database unit tests as part of your continuous integration script. If you have any trouble getting this up and running please let me know, either by commenting on this post, or email me directly using the email address below. Technorati Tags: SQL Server

    Read the article

  • Fun with Aggregates

    - by Paul White
    There are interesting things to be learned from even the simplest queries.  For example, imagine you are given the task of writing a query to list AdventureWorks product names where the product has at least one entry in the transaction history table, but fewer than ten. One possible query to meet that specification is: SELECT p.Name FROM Production.Product AS p JOIN Production.TransactionHistory AS th ON p.ProductID = th.ProductID GROUP BY p.ProductID, p.Name HAVING COUNT_BIG(*) < 10; That query correctly returns 23 rows (execution plan and data sample shown below): The execution plan looks a bit different from the written form of the query: the base tables are accessed in reverse order, and the aggregation is performed before the join.  The general idea is to read all rows from the history table, compute the count of rows grouped by ProductID, merge join the results to the Product table on ProductID, and finally filter to only return rows where the count is less than ten. This ‘fully-optimized’ plan has an estimated cost of around 0.33 units.  The reason for the quote marks there is that this plan is not quite as optimal as it could be – surely it would make sense to push the Filter down past the join too?  To answer that, let’s look at some other ways to formulate this query.  This being SQL, there are any number of ways to write logically-equivalent query specifications, so we’ll just look at a couple of interesting ones.  The first query is an attempt to reverse-engineer T-SQL from the optimized query plan shown above.  It joins the result of pre-aggregating the history table to the Product table before filtering: SELECT p.Name FROM ( SELECT th.ProductID, cnt = COUNT_BIG(*) FROM Production.TransactionHistory AS th GROUP BY th.ProductID ) AS q1 JOIN Production.Product AS p ON p.ProductID = q1.ProductID WHERE q1.cnt < 10; Perhaps a little surprisingly, we get a slightly different execution plan: The results are the same (23 rows) but this time the Filter is pushed below the join!  The optimizer chooses nested loops for the join, because the cardinality estimate for rows passing the Filter is a bit low (estimate 1 versus 23 actual), though you can force a merge join with a hint and the Filter still appears below the join.  In yet another variation, the < 10 predicate can be ‘manually pushed’ by specifying it in a HAVING clause in the “q1” sub-query instead of in the WHERE clause as written above. The reason this predicate can be pushed past the join in this query form, but not in the original formulation is simply an optimizer limitation – it does make efforts (primarily during the simplification phase) to encourage logically-equivalent query specifications to produce the same execution plan, but the implementation is not completely comprehensive. Moving on to a second example, the following query specification results from phrasing the requirement as “list the products where there exists fewer than ten correlated rows in the history table”: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) < 10 ); Unfortunately, this query produces an incorrect result (86 rows): The problem is that it lists products with no history rows, though the reasons are interesting.  The COUNT_BIG(*) in the EXISTS clause is a scalar aggregate (meaning there is no GROUP BY clause) and scalar aggregates always produce a value, even when the input is an empty set.  In the case of the COUNT aggregate, the result of aggregating the empty set is zero (the other standard aggregates produce a NULL).  To make the point really clear, let’s look at product 709, which happens to be one for which no history rows exist: -- Scalar aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709;   -- Vector aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709 GROUP BY th.ProductID; The estimated execution plans for these two statements are almost identical: You might expect the Stream Aggregate to have a Group By for the second statement, but this is not the case.  The query includes an equality comparison to a constant value (709), so all qualified rows are guaranteed to have the same value for ProductID and the Group By is optimized away. In fact there are some minor differences between the two plans (the first is auto-parameterized and qualifies for trivial plan, whereas the second is not auto-parameterized and requires cost-based optimization), but there is nothing to indicate that one is a scalar aggregate and the other is a vector aggregate.  This is something I would like to see exposed in show plan so I suggested it on Connect.  Anyway, the results of running the two queries show the difference at runtime: The scalar aggregate (no GROUP BY) returns a result of zero, whereas the vector aggregate (with a GROUP BY clause) returns nothing at all.  Returning to our EXISTS query, we could ‘fix’ it by changing the HAVING clause to reject rows where the scalar aggregate returns zero: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) BETWEEN 1 AND 9 ); The query now returns the correct 23 rows: Unfortunately, the execution plan is less efficient now – it has an estimated cost of 0.78 compared to 0.33 for the earlier plans.  Let’s try adding a redundant GROUP BY instead of changing the HAVING clause: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY th.ProductID HAVING COUNT_BIG(*) < 10 ); Not only do we now get correct results (23 rows), this is the execution plan: I like to compare that plan to quantum physics: if you don’t find it shocking, you haven’t understood it properly :)  The simple addition of a redundant GROUP BY has resulted in the EXISTS form of the query being transformed into exactly the same optimal plan we found earlier.  What’s more, in SQL Server 2008 and later, we can replace the odd-looking GROUP BY with an explicit GROUP BY on the empty set: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ); I offer that as an alternative because some people find it more intuitive (and it perhaps has more geek value too).  Whichever way you prefer, it’s rather satisfying to note that the result of the sub-query does not exist for a particular correlated value where a vector aggregate is used (the scalar COUNT aggregate always returns a value, even if zero, so it always ‘EXISTS’ regardless which ProductID is logically being evaluated). The following query forms also produce the optimal plan and correct results, so long as a vector aggregate is used (you can probably find more equivalent query forms): WHERE Clause SELECT p.Name FROM Production.Product AS p WHERE ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) < 10; APPLY SELECT p.Name FROM Production.Product AS p CROSS APPLY ( SELECT NULL FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ) AS ca (dummy); FROM Clause SELECT q1.Name FROM ( SELECT p.Name, cnt = ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) FROM Production.Product AS p ) AS q1 WHERE q1.cnt < 10; This last example uses SUM(1) instead of COUNT and does not require a vector aggregate…you should be able to work out why :) SELECT q.Name FROM ( SELECT p.Name, cnt = ( SELECT SUM(1) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID ) FROM Production.Product AS p ) AS q WHERE q.cnt < 10; The semantics of SQL aggregates are rather odd in places.  It definitely pays to get to know the rules, and to be careful to check whether your queries are using scalar or vector aggregates.  As we have seen, query plans do not show in which ‘mode’ an aggregate is running and getting it wrong can cause poor performance, wrong results, or both. © 2012 Paul White Twitter: @SQL_Kiwi email: [email protected]

    Read the article

  • Granular Clipboard Control in Oracle IRM

    - by martin.abrahams
    One of the main leak prevention controls that customers are looking for is clipboard control. After all, there is little point in controlling access to a document if authorised users can simply make unprotected copies by use of the cut and paste mechanism. Oddly, for such a fundamental requirement, many solutions only offer very simplistic clipboard control - and require the customer to make an awkward choice between usability and security. In many cases, clipboard control is simply an ON-OFF option. By turning the clipboard OFF, you disable one of the most valuable edit functions known to man. Try working for any length of time without copying and pasting, and you'll soon appreciate how valuable that function is. Worse, some solutions disable the clipboard completely - not just for the protected document but for all of the various applications you have open at the time. Normal service is only resumed when you close the protected document. In this way, policy enforcement bleeds out of the particular assets you need to protect and interferes with the entire user experience. On the other hand, turning the clipboard ON satisfies a fundamental usability requirement - but also makes it really easy for users to create unprotected copies of sensitive information, maliciously or otherwise. All they need to do is paste into another document. If creating unprotected copies is this simple, you have to question how much you are really gaining by applying protection at all. You may not be allowed to edit, forward, or print the protected asset, but all you need to do is create a copy and work with that instead. And that activity would not be tracked in any way. So, a simple ON-OFF control creates a real tension between usability and security. If you are only using IRM on a small scale, perhaps security can outweigh usability - the business can put up with the restriction if it only applies to a handful of important documents. But try extending protection to large numbers of documents and large user communities, and the restriction rapidly becomes really unwelcome. I am aware of one solution that takes a different tack. Rather than disable the clipboard, pasting is always permitted, but protection is automatically applied to any document that you paste into. At first glance, this sounds great - protection travels with the content. However, at any scale this model may not be so appealing once you've had to deal with support calls from users who have accidentally applied protection to documents that really don't need it - which would be all too easily done. This may help control leakage, but it also pollutes the system with documents that have policies applied with no obvious rhyme or reason, and it can seriously inconvenience the business by making non-sensitive documents difficult to access. And what policy applies if you paste some protected content into an already protected document? Which policy applies? There are no prizes for guessing that Oracle IRM takes a rather different approach. The Oracle IRM Approach Oracle IRM offers a spectrum of clipboard controls between the extremes of ON and OFF, and it leverages the classification-based rights model to give granular control that satisfies both security and usability needs. Firstly, we take it for granted that if you have EDIT rights, of course you can use the clipboard within a given document. Why would we force you to retype a piece of content that you want to move from HERE... to HERE...? If the pasted content remains in the same document, it is equally well protected whether it be at the beginning, middle, or end - or all three. So, the first point is that Oracle IRM always enables the clipboard if you have the right to edit the file. Secondly, whether we enable or disable the clipboard, we only affect the protected document. That is, you can continue to use the clipboard in the usual way for unprotected documents and applications regardless of whether the clipboard is enabled or disabled for the protected document(s). And if you have multiple protected documents open, each may have the clipboard enabled or disabled independently, according to whether you have Edit rights for each. So, even for the simplest cases - the ON-OFF cases - Oracle IRM adds value by containing the effect to the protected documents rather than to the whole desktop environment. Now to the granular options between ON and OFF. Thanks to our classification model, we can define rights that enable pasting between documents in the same classification - ie. between documents that are protected by the same policy. So, if you are working on this month's financial report and you want to pull some data from last month's report, you can simply cut and paste between the two documents. The two documents are classified the same way, subject to the same policy, so the content is equally safe in both documents. However, if you try to paste the same data into an unprotected document or a document in a different classification, you can be prevented. Thus, the control balances legitimate user requirements to allow pasting with legitimate information security concerns to keep data protected. We can take this further. You may have the right to paste between related classifications of document. So, the CFO might want to copy some financial data into a board document, where the two documents are sealed to different classifications. The CFO's rights may well allow this, as it is a reasonable thing for a CFO to want to do. But policy might prevent the CFO from copying the same data into a classification that is accessible to external parties. The above option, to copy between classifications, may be for specific classifications or open-ended. That is, your rights might enable you to go from A to B but not to C, or you might be allowed to paste to any classification subject to your EDIT rights. As for so many features of Oracle IRM, our classification-based rights model makes this type of granular control really easy to manage - you simply define that pasting is permitted between classifications A and B, but omit C. Or you might define that pasting is permitted between all classifications, but not to unprotected locations. The classification model enables millions of documents to be controlled by a few such rules. Finally, you MIGHT have the option to paste anywhere - such that unprotected copies may be created. This is rare, but a legitimate configuration for some users, some use cases, and some classifications - but not something that you have to permit simply because the alternative is too restrictive. As always, these rights are defined in user roles - so different users are subject to different clipboard controls as required in different classifications. So, where most solutions offer just two clipboard options - ON-OFF or ON-but-encrypt-everything-you-touch - Oracle IRM offers real granularity that leverages our classification model. Indeed, I believe it is the lack of a classification model that makes such granularity impractical for other IRM solutions, because the matrix of rules for controlling pasting would be impossible to manage - there are so many documents to consider, and more are being created all the time.

    Read the article

  • Openswan ipsec transport tunnel not going up

    - by gparent
    On ClusterA and B I have installed the "openswan" package on Debian Squeeze. ClusterA ip is 172.16.0.107, B is 172.16.0.108 When they ping one another, it does not reach the destination. /etc/ipsec.conf: version 2.0 # conforms to second version of ipsec.conf specification config setup protostack=netkey oe=off conn L2TP-PSK-CLUSTER type=transport left=172.16.0.107 right=172.16.0.108 auto=start ike=aes128-sha1-modp2048 authby=secret compress=yes /etc/ipsec.secrets: 172.16.0.107 172.16.0.108 : PSK "L2TPKEY" 172.16.0.108 172.16.0.107 : PSK "L2TPKEY" Here is the result of ipsec verify on both machines: root@cluster2:~# ipsec verify Checking your system to see if IPsec got installed and started correctly: Version check and ipsec on-path [OK] Linux Openswan U2.6.28/K2.6.32-5-amd64 (netkey) Checking for IPsec support in kernel [OK] NETKEY detected, testing for disabled ICMP send_redirects [OK] NETKEY detected, testing for disabled ICMP accept_redirects [OK] Checking that pluto is running [OK] Pluto listening for IKE on udp 500 [OK] Pluto listening for NAT-T on udp 4500 [FAILED] Checking for 'ip' command [OK] Checking for 'iptables' command [OK] Opportunistic Encryption Support [DISABLED] root@cluster2:~# This is the end of the output of ipsec auto --status: 000 "cluster": 172.16.0.108<172.16.0.108>[+S=C]...172.16.0.107<172.16.0.107>[+S=C]; prospective erouted; eroute owner: #0 000 "cluster": myip=unset; hisip=unset; 000 "cluster": ike_life: 3600s; ipsec_life: 28800s; rekey_margin: 540s; rekey_fuzz: 100%; keyingtries: 0 000 "cluster": policy: PSK+ENCRYPT+COMPRESS+PFS+UP+IKEv2ALLOW+lKOD+rKOD; prio: 32,32; interface: eth0; 000 "cluster": newest ISAKMP SA: #1; newest IPsec SA: #0; 000 "cluster": IKE algorithm newest: AES_CBC_128-SHA1-MODP2048 000 000 #3: "cluster":500 STATE_QUICK_R0 (expecting QI1); EVENT_CRYPTO_FAILED in 298s; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 #2: "cluster":500 STATE_QUICK_I1 (sent QI1, expecting QR1); EVENT_RETRANSMIT in 13s; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 #1: "cluster":500 STATE_MAIN_I4 (ISAKMP SA established); EVENT_SA_REPLACE in 2991s; newest ISAKMP; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 Interestingly enough, if I do ike-scan on the server here's what happens: Doesn't seem to take my ike settings into account root@cluster1:~# ike-scan -M 172.16.0.108 Starting ike-scan 1.9 with 1 hosts (http://www.nta-monitor.com/tools/ike-scan/) 172.16.0.108 Main Mode Handshake returned HDR=(CKY-R=641bffa66ba717b6) SA=(Enc=3DES Hash=SHA1 Auth=PSK Group=2:modp1024 LifeType=Seconds LifeDuration(4)=0x00007080) VID=4f45517b4f7f6e657a7b4351 VID=afcad71368a1f1c96b8696fc77570100 (Dead Peer Detection v1.0) Ending ike-scan 1.9: 1 hosts scanned in 0.008 seconds (118.19 hosts/sec). 1 returned handshake; 0 returned notify root@cluster1:~# I can't tell what's going on here, this is pretty much the simplest config I can have according to the examples.

    Read the article

  • Use BGInfo to Build a Database of System Information of Your Network Computers

    - by Sysadmin Geek
    One of the more popular tools of the Sysinternals suite among system administrators is BGInfo which tacks real-time system information to your desktop wallpaper when you first login. For obvious reasons, having information such as system memory, available hard drive space and system up time (among others) right in front of you is very convenient when you are managing several systems. A little known feature about this handy utility is the ability to have system information automatically saved to a SQL database or some other data file. With a few minutes of setup work you can easily configure BGInfo to record system information of all your network computers in a centralized storage location. You can then use this data to monitor or report on these systems however you see fit. BGInfo Setup If you are familiar with BGInfo, you can skip this section. However, if you have never used this tool, it takes just a few minutes to setup in order to capture the data you are looking for. When you first open BGInfo, a timer will be counting down in the upper right corner. Click the countdown button to keep the interface up so we can edit the settings. Now edit the information you want to capture from the available fields on the right. Since all the output will be redirected to a central location, don’t worry about configuring the layout or formatting. Configuring the Storage Database BGInfo supports the ability to store information in several database formats: SQL Server Database, Access Database, Excel and Text File. To configure this option, open File > Database. Using a Text File The simplest, and perhaps most practical, option is to store the BGInfo data in a comma separated text file. This format allows for the file to be opened in Excel or imported into a database. To use a text file or any other file system type (Excel or MS Access), simply provide the UNC to the respective file. The account running the task to write to this file will need read/write access to both the share and NTFS file permissions. When using a text file, the only option is to have BGInfo create a new entry each time the capture process is run which will add a new line to the respective CSV text file. Using a SQL Database If you prefer to have the data dropped straight into a SQL Server database, BGInfo support this as well. This requires a bit of additional configuration, but overall it is very easy. The first step is to create a database where the information will be stored. Additionally, you will want to create a user account to fill data into this table (and this table only). For your convenience, this script creates a new database and user account (run this as Administrator on your SQL Server machine): @SET Server=%ComputerName%.@SET Database=BGInfo@SET UserName=BGInfo@SET Password=passwordSQLCMD -S “%Server%” -E -Q “Create Database [%Database%]“SQLCMD -S “%Server%” -E -Q “Create Login [%UserName%] With Password=N’%Password%’, DEFAULT_DATABASE=[%Database%], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF”SQLCMD -S “%Server%” -E -d “%Database%” -Q “Create User [%UserName%] For Login [%UserName%]“SQLCMD -S “%Server%” -E -d “%Database%” -Q “EXEC sp_addrolemember N’db_owner’, N’%UserName%’” Note the SQL user account must have ‘db_owner’ permissions on the database in order for BGInfo to work correctly. This is why you should have a SQL user account specifically for this database. Next, configure BGInfo to connect to this database by clicking on the SQL button. Fill out the connection properties according to your database settings. Select the option of whether or not to only have one entry per computer or keep a history of each system. The data will then be dropped directly into a table named “BGInfoTable” in the respective database.   Configure User Desktop Options While the primary function of BGInfo is to alter the user’s desktop by adding system info as part of the wallpaper, for our use here we want to leave the user’s wallpaper alone so this process runs without altering any of the user’s settings. Click the Desktops button. Configure the Wallpaper modifications to not alter anything.   Preparing the Deployment Now we are all set for deploying the configuration to the individual machines so we can start capturing the system data. If you have not done so already, click the Apply button to create the first entry in your data repository. If all is configured correctly, you should be able to open your data file or database and see the entry for the respective machine. Now click the File > Save As menu option and save the configuration as “BGInfoCapture.bgi”.   Deploying to Client Machines Deployment to the respective client machines is pretty straightforward. No installation is required as you just need to copy the BGInfo.exe and the BGInfoCapture.bgi to each machine and place them in the same directory. Once in place, just run the command: BGInfo.exe BGInfoCapture.bgi /Timer:0 /Silent /NoLicPrompt Of course, you probably want to schedule the capture process to run on a schedule. This command creates a Scheduled Task to run the capture process at 8 AM every morning and assumes you copied the required files to the root of your C drive: SCHTASKS /Create /SC DAILY /ST 08:00 /TN “System Info” /TR “C:\BGInfo.exe C:\BGInfoCapture.bgi /Timer:0 /Silent /NoLicPrompt” Adjust as needed, but the end result is the scheduled task command should look something like this:   Download BGInfo from Sysinternals Latest Features How-To Geek ETC How To Create Your Own Custom ASCII Art from Any Image How To Process Camera Raw Without Paying for Adobe Photoshop How Do You Block Annoying Text Message (SMS) Spam? How to Use and Master the Notoriously Difficult Pen Tool in Photoshop HTG Explains: What Are the Differences Between All Those Audio Formats? How To Use Layer Masks and Vector Masks to Remove Complex Backgrounds in Photoshop Bring Summer Back to Your Desktop with the LandscapeTheme for Chrome and Iron The Prospector – Home Dash Extension Creates a Whole New Browsing Experience in Firefox KinEmote Links Kinect to Windows Why Nobody Reads Web Site Privacy Policies [Infographic] Asian Temple in the Snow Wallpaper 10 Weird Gaming Records from the Guinness Book

    Read the article

  • Creating an SMF service for mercurial web server

    - by Chris W Beal
    I'm working on a project at the moment, which has a number of contributers. We're managing the project gate (which is stand alone) with mercurial. We want to have an easy way of seeing the changelog, so we can show management what is going on.  Luckily mercurial provides a basic web server which allows you to see the changes, and drill in to change sets. This can be run as a daemon, but as it was running on our build server, every time it was rebooted, someone needed to remember to start the process again. This is of course a classic usage of SMF. Now I'm not an experienced person at writing SMF services, so it took me 1/2 an hour or so to figure it out the first time. But going forward I should know what I'm doing a bit better. I did reference this doc extensively. Taking a step back, the command to start the mercurial web server is $ hg serve -p <port number> -d So we somehow need to get SMF to run that command for us. In the simplest form, SMF services are really made up of two components. The manifest Usually lives in /var/svc/manifest somewhere Can be imported from any location The method Usually live in /lib/svc/method I simply put the script straight in that directory. Not very repeatable, but it worked Can take an argument of start, stop, or refresh Lets start with the manifest. This looks pretty complex, but all it's doing is describing the service name, the dependencies, the start and stop methods, and some properties. The properties can be by instance, that is to say I could have multiple hg serve processes handling different mercurial projects, on different ports simultaneously Here is the manifest I wrote. I stole extensively from the examples in the Documentation. So my manifest looks like this $ cat hg-serve.xml <?xml version="1.0"?> <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1"> <service_bundle type='manifest' name='hg-serve'> <service name='application/network/hg-serve' type='service' version='1'> <dependency name='network' grouping='require_all' restart_on='none' type='service'> <service_fmri value='svc:/milestone/network:default' /> </dependency> <exec_method type='method' name='start' exec='/lib/svc/method/hg-serve %m' timeout_seconds='2' /> <exec_method type='method' name='stop' exec=':kill' timeout_seconds='2'> </exec_method> <instance name='project-gate' enabled='true'> <method_context> <method_credential user='root' group='root' /> </method_context> <property_group name='hg-serve' type='application'> <propval name='path' type='astring' value='/src/project-gate'/> <propval name='port' type='astring' value='9998' /> </property_group> </instance> <stability value='Evolving' /> <template> <common_name> <loctext xml:lang='C'>hg-serve</loctext> </common_name> <documentation> <manpage title='hg' section='1' /> </documentation> </template> </service> </service_bundle> So the only things I had to decide on in this are the service name "application/network/hg-serve" the start and stop methods (more of which later) and the properties. This is the information I need to pass to the start method script. In my case the port I want to start the web server on "9998", and the path to the source gate "/src/project-gate". These can be read in to the start method. So now lets look at the method scripts $ cat /lib/svc/method/hg-serve #!/sbin/sh # # # Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved. # # Standard prolog # . /lib/svc/share/smf_include.sh if [ -z $SMF_FMRI ]; then echo "SMF framework variables are not initialized." exit $SMF_EXIT_ERR fi # # Build the command line flags # # Get the port and directory from the SMF properties port=`svcprop -c -p hg-serve/port $SMF_FMRI` dir=`svcprop -c -p hg-serve/path $SMF_FMRI` echo "$1" case "$1" in 'start') cd $dir /usr/bin/hg serve -d -p $port ;; *) echo "Usage: $0 {start|refresh|stop}" exit 1 ;; esac exit $SMF_EXIT_OK This is all pretty self explanatory, we read the port and directory using svcprop, and use those simply to run a command in the start case. We don't need to implement a stop case, as the manifest says to use "exec=':kill'for the stop method. Now all we need to do is import the manifest and start the service, but first verify the manifest # svccfg verify /path/to/hg-serve.xml If that doesn't give an error try importing it # svccfg import /path/to/hg-serve.xml If like me you originally put the hg-serve.xml file in /var/svc/manifest somewhere you'll get an error and told to restart the import service svccfg: Restarting svc:/system/manifest-import The manifest being imported is from a standard location and should be imported with the command : svcadm restart svc:/system/manifest-import # svcadm restart svc:/system/manifest-import and you're nearly done. You can look at the service using svcs -l # svcs -l hg-serve fmri svc:/application/network/hg-serve:project-gate name hg-serve enabled false state disabled next_state none state_time Thu May 31 16:11:47 2012 logfile /var/svc/log/application-network-hg-serve:project-gate.log restarter svc:/system/svc/restarter:default contract_id 15749 manifest /var/svc/manifest/network/hg/hg-serve.xml dependency require_all/none svc:/milestone/network:default (online) And look at the interesting properties # svcprop hg-serve hg-serve/path astring /src/project-gate hg-serve/port astring 9998 ...stuff deleted.... Then simply enable the service and if every things gone right, you can point your browser at http://server:9998 and get a nice graphical log of project activity. # svcadm enable hg-serve # svcs -l hg-serve fmri svc:/application/network/hg-serve:project-gate name hg-serve enabled true state online next_state none state_time Thu May 31 16:18:11 2012 logfile /var/svc/log/application-network-hg-serve:project-gate.log restarter svc:/system/svc/restarter:default contract_id 15858 manifest /var/svc/manifest/network/hg/hg-serve.xml dependency require_all/none svc:/milestone/network:default (online) None of this is rocket science, but a bit fiddly. Hence I thought I'd blog it. It might just be you see this in google and it clicks with you more than one of the many other blogs or how tos about it. Plus I can always refer back to it myself in 3 weeks, when I want to add another project to the server, and I've forgotten how to do it.

    Read the article

  • SQL SERVER – Core Concepts – Elasticity, Scalability and ACID Properties – Exploring NuoDB an Elastically Scalable Database System

    - by pinaldave
    I have been recently exploring Elasticity and Scalability attributes of databases. You can see that in my earlier blog posts about NuoDB where I wanted to look at Elasticity and Scalability concepts. The concepts are very interesting, and intriguing as well. I have discussed these concepts with my friend Joyti M and together we have come up with this interesting read. The goal of this article is to answer following simple questions What is Elasticity? What is Scalability? How ACID properties vary from NOSQL Concepts? What are the prevailing problems in the current database system architectures? Why is NuoDB  an innovative and welcome change in database paradigm? Elasticity This word’s original form is used in many different ways and honestly it does do a decent job in holding things together over the years as a person grows and contracts. Within the tech world, and specifically related to software systems (database, application servers), it has come to mean a few things - allow stretching of resources without reaching the breaking point (on demand). What are resources in this context? Resources are the usual suspects – RAM/CPU/IO/Bandwidth in the form of a container (a process or bunch of processes combined as modules). When it is about increasing resources the simplest idea which comes to mind is the addition of another container. Another container means adding a brand new physical node. When it is about adding a new node there are two questions which comes to mind. 1) Can we add another node to our software system? 2) If yes, does adding new node cause downtime for the system? Let us assume we have added new node, let us see what the new needs of the system are when a new node is added. Balancing incoming requests to multiple nodes Synchronization of a shared state across multiple nodes Identification of “downstate” and resolution action to bring it to “upstate” Well, adding a new node has its advantages as well. Here are few of the positive points Throughput can increase nearly horizontally across the node throughout the system Response times of application will increase as in-between layer interactions will be improved Now, Let us put the above concepts in the perspective of a Database. When we mention the term “running out of resources” or “application is bound to resources” the resources can be CPU, Memory or Bandwidth. The regular approach to “gain scalability” in the database is to look around for bottlenecks and increase the bottlenecked resource. When we have memory as a bottleneck we look at the data buffers, locks, query plans or indexes. After a point even this is not enough as there needs to be an efficient way of managing such large workload on a “single machine” across memory and CPU bound (right kind of scheduling)  workload. We next move on to either read/write separation of the workload or functionality-based sharing so that we still have control of the individual. But this requires lots of planning and change in client systems in terms of knowing where to go/update/read and for reporting applications to “aggregate the data” in an intelligent way. What we ideally need is an intelligent layer which allows us to do these things without us getting into managing, monitoring and distributing the workload. Scalability In the context of database/applications, scalability means three main things Ability to handle normal loads without pressure E.g. X users at the Y utilization of resources (CPU, Memory, Bandwidth) on the Z kind of hardware (4 processor, 32 GB machine with 15000 RPM SATA drives and 1 GHz Network switch) with T throughput Ability to scale up to expected peak load which is greater than normal load with acceptable response times Ability to provide acceptable response times across the system E.g. Response time in S milliseconds (or agreed upon unit of measure) – 90% of the time The Issue – Need of Scale In normal cases one can plan for the load testing to test out normal, peak, and stress scenarios to ensure specific hardware meets the needs. With help from Hardware and Software partners and best practices, bottlenecks can be identified and requisite resources added to the system. Unfortunately this vertical scale is expensive and difficult to achieve and most of the operational people need the ability to scale horizontally. This helps in getting better throughput as there are physical limits in terms of adding resources (Memory, CPU, Bandwidth and Storage) indefinitely. Today we have different options to achieve scalability: Read & Write Separation The idea here is to do actual writes to one store and configure slaves receiving the latest data with acceptable delays. Slaves can be used for balancing out reads. We can also explore functional separation or sharing as well. We can separate data operations by a specific identifier (e.g. region, year, month) and consolidate it for reporting purposes. For functional separation the major disadvantage is when schema changes or workload pattern changes. As the requirement grows one still needs to deal with scale need in manual ways by providing an abstraction in the middle tier code. Using NOSQL solutions The idea is to flatten out the structures in general to keep all values which are retrieved together at the same store and provide flexible schema. The issue with the stores is that they are compromising on mostly consistency (no ACID guarantees) and one has to use NON-SQL dialect to work with the store. The other major issue is about education with NOSQL solutions. Would one really want to make these compromises on the ability to connect and retrieve in simple SQL manner and learn other skill sets? Or for that matter give up on ACID guarantee and start dealing with consistency issues? Hybrid Deployment – Mac, Linux, Cloud, and Windows One of the challenges today that we see across On-premise vs Cloud infrastructure is a difference in abilities. Take for example SQL Azure – it is wonderful in its concepts of throttling (as it is shared deployment) of resources and ability to scale using federation. However, the same abilities are not available on premise. This is not a mistake, mind you – but a compromise of the sweet spot of workloads, customer requirements and operational SLAs which can be supported by the team. In today’s world it is imperative that databases are available across operating systems – which are a commodity and used by developers of all hues. An Ideal Database Ability List A system which allows a linear scale of the system (increase in throughput with reasonable response time) with the addition of resources A system which does not compromise on the ACID guarantees and require developers to learn new paradigms A system which does not force fit a new way interacting with database by learning Non-SQL dialect A system which does not force fit its mechanisms for providing availability across its various modules. Well NuoDB is the first database which has all of the above abilities and much more. In future articles I will cover my hands-on experience with it. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: NuoDB

    Read the article

  • Anatomy of a .NET Assembly - CLR metadata 1

    - by Simon Cooper
    Before we look at the bytes comprising the CLR-specific data inside an assembly, we first need to understand the logical format of the metadata (For this post I only be looking at simple pure-IL assemblies; mixed-mode assemblies & other things complicates things quite a bit). Metadata streams Most of the CLR-specific data inside an assembly is inside one of 5 streams, which are analogous to the sections in a PE file. The name of each section in a PE file starts with a ., and the name of each stream in the CLR metadata starts with a #. All but one of the streams are heaps, which store unstructured binary data. The predefined streams are: #~ Also called the metadata stream, this stream stores all the information on the types, methods, fields, properties and events in the assembly. Unlike the other streams, the metadata stream has predefined contents & structure. #Strings This heap is where all the namespace, type & member names are stored. It is referenced extensively from the #~ stream, as we'll be looking at later. #US Also known as the user string heap, this stream stores all the strings used in code directly. All the strings you embed in your source code end up in here. This stream is only referenced from method bodies. #GUID This heap exclusively stores GUIDs used throughout the assembly. #Blob This heap is for storing pure binary data - method signatures, generic instantiations, that sort of thing. Items inside the heaps (#Strings, #US, #GUID and #Blob) are indexed using a simple binary offset from the start of the heap. At that offset is a coded integer giving the length of that item, then the item's bytes immediately follow. The #GUID stream is slightly different, in that GUIDs are all 16 bytes long, so a length isn't required. Metadata tables The #~ stream contains all the assembly metadata. The metadata is organised into 45 tables, which are binary arrays of predefined structures containing information on various aspects of the metadata. Each entry in a table is called a row, and the rows are simply concatentated together in the file on disk. For example, each row in the TypeRef table contains: A reference to where the type is defined (most of the time, a row in the AssemblyRef table). An offset into the #Strings heap with the name of the type An offset into the #Strings heap with the namespace of the type. in that order. The important tables are (with their table number in hex): 0x2: TypeDef 0x4: FieldDef 0x6: MethodDef 0x14: EventDef 0x17: PropertyDef Contains basic information on all the types, fields, methods, events and properties defined in the assembly. 0x1: TypeRef The details of all the referenced types defined in other assemblies. 0xa: MemberRef The details of all the referenced members of types defined in other assemblies. 0x9: InterfaceImpl Links the types defined in the assembly with the interfaces that type implements. 0xc: CustomAttribute Contains information on all the attributes applied to elements in this assembly, from method parameters to the assembly itself. 0x18: MethodSemantics Links properties and events with the methods that comprise the get/set or add/remove methods of the property or method. 0x1b: TypeSpec 0x2b: MethodSpec These tables provide instantiations of generic types and methods for each usage within the assembly. There are several ways to reference a single row within a table. The simplest is to simply specify the 1-based row index (RID). The indexes are 1-based so a value of 0 can represent 'null'. In this case, which table the row index refers to is inferred from the context. If the table can't be determined from the context, then a particular row is specified using a token. This is a 4-byte value with the most significant byte specifying the table, and the other 3 specifying the 1-based RID within that table. This is generally how a metadata table row is referenced from the instruction stream in method bodies. The third way is to use a coded token, which we will look at in the next post. So, back to the bytes Now we've got a rough idea of how the metadata is logically arranged, we can now look at the bytes comprising the start of the CLR data within an assembly: The first 8 bytes of the .text section are used by the CLR loader stub. After that, the CLR-specific data starts with the CLI header. I've highlighted the important bytes in the diagram. In order, they are: The size of the header. As the header is a fixed size, this is always 0x48. The CLR major version. This is always 2, even for .NET 4 assemblies. The CLR minor version. This is always 5, even for .NET 4 assemblies, and seems to be ignored by the runtime. The RVA and size of the metadata header. In the diagram, the RVA 0x20e4 corresponds to the file offset 0x2e4 Various flags specifying if this assembly is pure-IL, whether it is strong name signed, and whether it should be run as 32-bit (this is how the CLR differentiates between x86 and AnyCPU assemblies). A token pointing to the entrypoint of the assembly. In this case, 06 (the last byte) refers to the MethodDef table, and 01 00 00 refers to to the first row in that table. (after a gap) RVA of the strong name signature hash, which comes straight after the CLI header. The RVA 0x2050 corresponds to file offset 0x250. The rest of the CLI header is mainly used in mixed-mode assemblies, and so is zeroed in this pure-IL assembly. After the CLI header comes the strong name hash, which is a SHA-1 hash of the assembly using the strong name key. After that comes the bodies of all the methods in the assembly concatentated together. Each method body starts off with a header, which I'll be looking at later. As you can see, this is a very small assembly with only 2 methods (an instance constructor and a Main method). After that, near the end of the .text section, comes the metadata, containing a metadata header and the 5 streams discussed above. We'll be looking at this in the next post. Conclusion The CLI header data doesn't have much to it, but we've covered some concepts that will be important in later posts - the logical structure of the CLR metadata and the overall layout of CLR data within the .text section. Next, I'll have a look at the contents of the #~ stream, and how the table data is arranged on disk.

    Read the article

  • Using Apache FOP from .NET level

    - by Lukasz Kurylo
    In one of my previous posts I was talking about FO.NET which I was using to generate a pdf documents from XSL-FO. FO.NET is one of the .NET ports of Apache FOP. Unfortunatelly it is no longer maintained. I known it when I decidec to use it, because there is a lack of available (free) choices for .NET to render a pdf form XSL-FO. I hoped in this implementation I will find all I need to create a pdf file with my really simple requirements. FO.NET is a port from some old version of Apache FOP and I found really quickly that there is a lack of some features that I needed, like dotted borders, double borders or support for margins. So I started to looking for some alternatives. I didn’t try the NFOP, another port of Apache FOP, because I found something I think much more better, the IKVM.NET project.   IKVM.NET it is not a pdf renderer. So what it is? From the project site:   IKVM.NET is an implementation of Java for Mono and the Microsoft .NET Framework. It includes the following components: a Java Virtual Machine implemented in .NET a .NET implementation of the Java class libraries tools that enable Java and .NET interoperability   In the simplest form IKVM.NET allows to use a Java code library in the C# code and vice versa.   I tried to use an Apache FOP, the best I think open source pdf –> XSL-FO renderer written in Java from my project written in C# using an IKVM.NET and it work like a charm. In the rest of the post I want to show, how to prepare a .NET *.dll class library from Apache FOP *.jar’s with IKVM.NET and generate a simple Hello world pdf document.   To start playing with IKVM.NET and Apache FOP we need to download their packages: IKVM.NET Apache FOP and then unpack them.   From the FOP directory copy all the *.jar’s files from lib and build catalogs to some location, e.g. d:\fop. Second step is to build the *.dll library from these files. On the console execute the following comand:   ikvmc –target:library –out:d:\fop\fop.dll –recurse:d:\fop   The ikvmc is located in the bin subdirectory where you unpacked the IKVM.NET. You must execute this command from this catalog, add this path to the global variable PATH or specify the full path to the bin subdirectory.   In no error occurred during this process, the fop.dll library should be created. Right now we can create a simple project to test if we can create a pdf file.   So let’s create a simple console project application and add reference to the fop.dll and the IKVM dll’s: IKVM.OpenJDK.Core and IKVM.OpenJDK.XML.API.   Full code to generate a pdf file from XSL-FO template:   static void Main(string[] args)         {             //initialize the Apache FOP             FopFactory fopFactory = FopFactory.newInstance();               //in this stream we will get the generated pdf file             OutputStream o = new DotNetOutputMemoryStream();             try             {                 Fop fop = fopFactory.newFop("application/pdf", o);                 TransformerFactory factory = TransformerFactory.newInstance();                 Transformer transformer = factory.newTransformer();                   //read the template from disc                 Source src = new StreamSource(new File("HelloWorld.fo"));                 Result res = new SAXResult(fop.getDefaultHandler());                 transformer.transform(src, res);             }             finally             {                 o.close();             }             using (System.IO.FileStream fs = System.IO.File.Create("HelloWorld.pdf"))             {                 //write from the .NET MemoryStream stream to disc the generated pdf file                 var data = ((DotNetOutputMemoryStream)o).Stream.GetBuffer();                 fs.Write(data, 0, data.Length);             }             Process.Start("HelloWorld.pdf");             System.Console.ReadLine();         }   Apache FOP be default using a Java’s Xalan to work with XML files. I didn’t find a way to replace this piece of code with equivalent from .NET standard library. If any error or warning will occure during generating the pdf file, on the console will ge shown, that’s why I inserted the last line in the sample above. The DotNetOutputMemoryStream this is my wrapper for the Java OutputStream. I have created it to have the possibility to exchange data between the .NET <-> Java objects. It’s implementation:   class DotNetOutputMemoryStream : OutputStream     {         private System.IO.MemoryStream ms = new System.IO.MemoryStream();         public System.IO.MemoryStream Stream         {             get             {                 return ms;             }         }         public override void write(int i)         {             ms.WriteByte((byte)i);         }         public override void write(byte[] b, int off, int len)         {             ms.Write(b, off, len);         }         public override void write(byte[] b)         {             ms.Write(b, 0, b.Length);         }         public override void close()         {             ms.Close();         }         public override void flush()         {             ms.Flush();         }     } The last thing we need, this is the HelloWorld.fo template.   <?xml version="1.0" encoding="utf-8"?> <fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format"          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">   <fo:layout-master-set>     <fo:simple-page-master master-name="simple"                   page-height="29.7cm"                   page-width="21cm"                   margin-top="1.8cm"                   margin-bottom="0.8cm"                   margin-left="1.6cm"                   margin-right="1.2cm">       <fo:region-body margin-top="3cm"/>       <fo:region-before extent="3cm"/>       <fo:region-after extent="1.5cm"/>     </fo:simple-page-master>   </fo:layout-master-set>   <fo:page-sequence master-reference="simple">     <fo:flow flow-name="xsl-region-body">       <fo:block font-size="18pt" color="black" text-align="center">         Hello, World!       </fo:block>     </fo:flow>   </fo:page-sequence> </fo:root>   I’m not going to explain how how this template is created, because this will be covered in the near future posts.   Generated pdf file should look that:

    Read the article

  • Developing a Cost Model for Cloud Applications

    - by BuckWoody
    Note - please pay attention to the date of this post. As much as I attempt to make the information below accurate, the nature of distributed computing means that components, units and pricing will change over time. The definitive costs for Microsoft Windows Azure and SQL Azure are located here, and are more accurate than anything you will see in this post: http://www.microsoft.com/windowsazure/offers/  When writing software that is run on a Platform-as-a-Service (PaaS) offering like Windows Azure / SQL Azure, one of the questions you must answer is how much the system will cost. I will not discuss the comparisons between on-premise costs (which are nigh impossible to calculate accurately) versus cloud costs, but instead focus on creating a general model for estimating costs for a given application. You should be aware that there are (at this writing) two billing mechanisms for Windows and SQL Azure: “Pay-as-you-go” or consumption, and “Subscription” or commitment. Conceptually, you can consider the former a pay-as-you-go cell phone plan, where you pay by the unit used (at a slightly higher rate) and the latter as a standard cell phone plan where you commit to a contract and thus pay lower rates. In this post I’ll stick with the pay-as-you-go mechanism for simplicity, which should be the maximum cost you would pay. From there you may be able to get a lower cost if you use the other mechanism. In any case, the model you create should hold. Developing a good cost model is essential. As a developer or architect, you’ll most certainly be asked how much something will cost, and you need to have a reliable way to estimate that. Businesses and Organizations have been used to paying for servers, software licenses, and other infrastructure as an up-front cost, and power, people to the systems and so on as an ongoing (and sometimes not factored) cost. When presented with a new paradigm like distributed computing, they may not understand the true cost/value proposition, and that’s where the architect and developer can guide the conversation to make a choice based on features of the application versus the true costs. The two big buckets of use-types for these applications are customer-based and steady-state. In the customer-based use type, each successful use of the program results in a sale or income for your organization. Perhaps you’ve written an application that provides the spot-price of foo, and your customer pays for the use of that application. In that case, once you’ve estimated your cost for a successful traversal of the application, you can build that into the price you charge the user. It’s a standard restaurant model, where the price of the meal is determined by the cost of making it, plus any profit you can make. In the second use-type, the application will be used by a more-or-less constant number of processes or users and no direct revenue is attached to the system. A typical example is a customer-tracking system used by the employees within your company. In this case, the cost model is often created “in reverse” - meaning that you pilot the application, monitor the use (and costs) and that cost is held steady. This is where the comparison with an on-premise system becomes necessary, even though it is more difficult to estimate those on-premise true costs. For instance, do you know exactly how much cost the air conditioning is because you have a team of system administrators? This may sound trivial, but that, along with the insurance for the building, the wiring, and every other part of the system is in fact a cost to the business. There are three primary methods that I’ve been successful with in estimating the cost. None are perfect, all are demand-driven. The general process is to lay out a matrix of: components units cost per unit and then multiply that times the usage of the system, based on which components you use in the program. That sounds a bit simplistic, but using those metrics in a calculation becomes more detailed. In all of the methods that follow, you need to know your application. The components for a PaaS include computing instances, storage, transactions, bandwidth and in the case of SQL Azure, database size. In most cases, architects start with the first model and progress through the other methods to gain accuracy. Simple Estimation The simplest way to calculate costs is to architect the application (even UML or on-paper, no coding involved) and then estimate which of the components you’ll use, and how much of each will be used. Microsoft provides two tools to do this - one is a simple slider-application located here: http://www.microsoft.com/windowsazure/pricing-calculator/  The other is a tool you download to create an “Return on Investment” (ROI) spreadsheet, which has the advantage of leading you through various questions to estimate what you plan to use, located here: https://roianalyst.alinean.com/msft/AutoLogin.do?d=176318219048082115  You can also just create a spreadsheet yourself with a structure like this: Program Element Azure Component Unit of Measure Cost Per Unit Estimated Use of Component Total Cost Per Component Cumulative Cost               Of course, the consideration with this model is that it is difficult to predict a system that is not running or hasn’t even been developed. Which brings us to the next model type. Measure and Project A more accurate model is to actually write the code for the application, using the Software Development Kit (SDK) which can run entirely disconnected from Azure. The code should be instrumented to estimate the use of the application components, logging to a local file on the development system. A series of unit and integration tests should be run, which will create load on the test system. You can use standard development concepts to track this usage, and even use Windows Performance Monitor counters. The best place to start with this method is to use the Windows Azure Diagnostics subsystem in your code, which you can read more about here: http://blogs.msdn.com/b/sumitm/archive/2009/11/18/introducing-windows-azure-diagnostics.aspx This set of API’s greatly simplifies tracking the application, and in fact you can use this information for more than just a cost model. After you have the tracking logs, you can plug the numbers into ay of the tools above, which should give a representative cost or in some cases a unit cost. The consideration with this model is that the SDK fabric is not a one-to-one comparison with performance on the actual Windows Azure fabric. Those differences are usually smaller, but they do need to be considered. Also, you may not be able to accurately predict the load on the system, which might lead to an architectural change, which changes the model. This leads us to the next, most accurate method for a cost model. Sample and Estimate Using standard statistical and other predictive math, once the application is deployed you will get a bill each month from Microsoft for your Azure usage. The bill is quite detailed, and you can export the data from it to do analysis, and using methods like regression and so on project out into the future what the costs will be. I normally advise that the architect also extrapolate a unit cost from those metrics as well. This is the information that should be reported back to the executives that pay the bills: the past cost, future projected costs, and unit cost “per click” or “per transaction”, as your case warrants. The challenge here is in the model itself - statistical methods are not foolproof, and the larger the sample (in this case I recommend the entire population, not a smaller sample) is key. References and Tools Articles: http://blogs.msdn.com/b/patrick_butler_monterde/archive/2010/02/10/windows-azure-billing-overview.aspx http://technet.microsoft.com/en-us/magazine/gg213848.aspx http://blog.codingoutloud.com/2011/06/05/azure-faq-how-much-will-it-cost-me-to-run-my-application-on-windows-azure/ http://blogs.msdn.com/b/johnalioto/archive/2010/08/25/10054193.aspx http://geekswithblogs.net/iupdateable/archive/2010/02/08/qampa-how-can-i-calculate-the-tco-and-roi-when.aspx   Other Tools: http://cloud-assessment.com/ http://communities.quest.com/community/cloud_tools

    Read the article

  • Agile Like Jazz

    - by Jeff Certain
    (I’ve been sitting on this for a week or so now, thinking that it needed to be tightened up a bit to make it less rambling. Since that’s clearly not going to happen, reader beware!) I had the privilege of spending around 90 minutes last night sitting and listening to Sonny Rollins play a concert at the Disney Center in LA. If you don’t know who Sonny Rollins is, I don’t know how to explain the experience; if you know who he is, I don’t need to. Suffice it to say that he has been recording professionally for over 50 years, and helped create an entire genre of music. A true master by any definition. One of the most intriguing aspects of a concert like this, however, is watching the master step aside and let the rest of the musicians play. Not just play their parts, but really play… letting them take over the spotlight, to strut their stuff, to soak up enthusiastic applause from the crowd. Maybe a lot of it has to do with the fact that Sonny Rollins has been doing this for more than a half-century. Maybe it has something to do with a kind of patience you learn when you’re on the far side of 80 – and the man can still blow a mean sax for 90 minutes without stopping! Maybe it has to do with the fact that he was out there for the love of the music and the love of the show, not because he had anything to prove to anyone and, I like to think, not for the money. Perhaps it had more to do with the fact that, when you’re at that level of mastery, the other musicians are going to be good. Really good. Whatever the reasons, there was a incredible freedom on that stage – the ability to improvise, for each musician to showcase their own specialization and skills, and them come back to the common theme, back to being on the same page, as it were. All this took place in the same venue that is home to the L.A. Phil. Somehow, I can’t ever see the same kind of free-wheeling improvisation happening in that context. And, since I’m a geek, I started thinking about agility. Rollins has put together a quintet that reflects his own particular style and past. No upright bass or piano for Rollins – drums, bongos, electric guitar and bass guitar along with his sax. It’s not about the mix of instruments. Other trios, quartets, and sextets use different mixes of instruments. New Orleans jazz tends towards trombones instead of sax; some prefer cornet or trumpet. But no matter what the choice of instruments, size matters. Team sizes are something I’ve been thinking about for a while. We’re on a quest to rethink how our teams are organized. They just feel too big, too unwieldy. In fact, they really don’t feel like teams at all. Most of the time, they feel more like collections or people who happen to report to the same manager. I attribute this to a couple factors. One is over-specialization; we have a tendency to have people work in silos. Although the teams are product-focused, within them our developers are both generalists and specialists. On the one hand, we expect them to be able to build an entire vertical slice of the application; on the other hand, each developer tends to be responsible for the vertical slice. As a result, developers often work on their own piece of the puzzle, in isolation. This sort of feels like working on a jigsaw in a group – each person taking a set of colors and piecing them together to reveal a portion of the overall picture. But what inevitably happens when you go to meld all those pieces together? Inevitably, you have some sections that are too big to move easily. These sections end up falling apart under their own weight as you try to move them. Not only that, but there are other challenges – figuring out where that section fits, and how to tie it into the rest of the puzzle. Often, this is when you find a few pieces need to be added – these pieces are “glue,” if you will. The other issue that arises is due to the overhead of maintaining communications in a team. My mother, who worked in IT for around 30 years, once told me that 20% per team member is a good rule of thumb for maintaining communication. While this is a rule of thumb, it seems to imply that any team over about 6 people is going to become less agile simple because of the communications burden. Teams of ten or twelve seem like they fall into the philharmonic organizational model. Complicated pieces of music requiring dozens of players to all be on the same page requires a much different model than the jazz quintet. There’s much less room for improvisation, originality or freedom. (There are probably orchestral musicians who will take exception to this characterization; I’m calling it like I see it from the cheap seats.) And, there’s one guy up front who is running the show, whose job is to keep all of those dozens of players on the same page, to facilitate communications. Somehow, the orchestral model doesn’t feel much like a self-organizing team, either. The first violin may be the best violinist in the orchestra, but they don’t get to perform free-wheeling solos. I’ve never heard of an orchestra getting together for a jam session. But I have heard of teams that organize their work based on the developers available, rather than organizing the developers based on the work required. I have heard of teams where desired functionality is deferred – or worse yet, schedules are missed – because one critical person doesn’t have any bandwidth available. I’ve heard of teams where people simply don’t have the big picture, because there is too much communication overhead for everyone to be aware of everything that is happening on a project. I once heard Paul Rayner say something to the effect of “you have a process that is perfectly designed to give you exactly the results you have.” Given a choice, I want a process that’s much more like jazz than orchestral music. I want a process that doesn’t burden me with lots of forms and checkboxes and stuff. Give me the simplest, most lightweight process that will work – and a smaller team of the best developers I can find. This seems like the kind of process that will get the kind of result I want to be part of.

    Read the article

  • Unlocking Productivity

    - by Michael Snow
    Unlocking Productivity in Life Sciences with Consolidated Content Management by Joe Golemba, Vice President, Product Management, Oracle WebCenter As life sciences organizations look to become more operationally efficient, the ability to effectively leverage information is a competitive advantage. Whether data mining at the drug discovery phase or prepping the sales team before a product launch, content management can play a key role in developing, organizing, and disseminating vital information. The goal of content management is relatively straightforward: put the information that people need where they can find it. A number of issues can complicate this; information sits in many different systems, each of those systems has its own security, and the information in those systems exists in many different formats. Identifying and extracting pertinent information from mountains of farflung data is no simple job, but the alternative—wasted effort or even regulatory compliance issues—is worse. An integrated information architecture can enable health sciences organizations to make better decisions, accelerate clinical operations, and be more competitive. Unstructured data matters Often when we think of drug development data, we think of structured data that fits neatly into one or more research databases. But structured data is often directly supported by unstructured data such as experimental protocols, reaction conditions, lot numbers, run times, analyses, and research notes. As life sciences companies seek integrated views of data, they are typically finding diverse islands of data that seemingly have no relationship to other data in the organization. Information like sales reports or call center reports can be locked into siloed systems, and unavailable to the discovery process. Additionally, in the increasingly networked clinical environment, Web pages, instant messages, videos, scientific imaging, sales and marketing data, collaborative workspaces, and predictive modeling data are likely to be present within an organization, and each source potentially possesses information that can help to better inform specific efforts. Historically, content management solutions that had 21CFR Part 11 capabilities—electronic records and signatures—were focused mainly on content-enabling manufacturing-related processes. Today, life sciences companies have many standalone repositories, requiring different skills, service level agreements, and vendor support costs to manage them. With the amount of content doubling every three to six months, companies have recognized the need to manage unstructured content from the beginning, in order to increase employee productivity and operational efficiency. Using scalable and secure enterprise content management (ECM) solutions, organizations can better manage their unstructured content. These solutions can also be integrated with enterprise resource planning (ERP) systems or research systems, making content available immediately, in the context of the application and within the flow of the employee’s typical business activity. Administrative safeguards—such as content de-duplication—can also be applied within ECM systems, so documents are never recreated, eliminating redundant efforts, ensuring one source of truth, and maintaining content standards in the organization. Putting it in context Consolidating structured and unstructured information in a single system can greatly simplify access to relevant information when it is needed through contextual search. Using contextual filters, results can include therapeutic area, position in the value chain, semantic commonalities, technology-specific factors, specific researchers involved, or potential business impact. The use of taxonomies is essential to organizing information and enabling contextual searches. Taxonomy solutions are composed of a hierarchical tree that defines the relationship between different life science terms. When overlaid with additional indexing related to research and/or business processes, it becomes possible to effectively narrow down the amount of data that is returned during searches, as well as prioritize results based on specific criteria and/or prior search history. Thus, search results are more accurate and relevant to an employee’s day-to-day work. For example, a search for the word "tissue" by a lab researcher would return significantly different results than a search for the same word performed by someone in procurement. Of course, diverse data repositories, combined with the immense amounts of data present in an organization, necessitate that the data elements be regularly indexed and cached beforehand to enable reasonable search response times. In its simplest form, indexing of a single, consolidated data warehouse can be expected to be a relatively straightforward effort. However, organizations require the ability to index multiple data repositories, enabling a single search to reference multiple data sources and provide an integrated results listing. Security and compliance Beyond yielding efficiencies and supporting new insight, an enterprise search environment can support important security considerations as well as compliance initiatives. For example, the systems enable organizations to retain the relevance and the security of the indexed systems, so users can only see the results to which they are granted access. This is especially important as life sciences companies are working in an increasingly networked environment and need to provide secure, role-based access to information across multiple partners. Although not officially required by the 21 CFR Part 11 regulation, the U.S. Food and Drug Administraiton has begun to extend the type of content considered when performing relevant audits and discoveries. Having an ECM infrastructure that provides centralized management of all content enterprise-wide—with the ability to consistently apply records and retention policies along with the appropriate controls, validations, audit trails, and electronic signatures—is becoming increasingly critical for life sciences companies. Making the move Creating an enterprise-wide ECM environment requires moving large amounts of content into a single enterprise repository, a daunting and risk-laden initiative. The first key is to focus on data taxonomy, allowing content to be mapped across systems. The second is to take advantage new tools which can dramatically speed and reduce the cost of the data migration process through automation. Additional content need not be frozen while it is migrated, enabling productivity throughout the process. The ability to effectively leverage information into success has been gaining importance in the life sciences industry for years. The rapid adoption of enterprise content management, both in operational processes as well as in scientific management, are clear indicators that the companies are looking to use all available data to be better informed, improve decision making, minimize risk, and increase time to market, to maintain profitability and be more competitive. As more and more varieties and sources of information are brought under the strategic management umbrella, the ability to divine knowledge from the vast pool of information is increasingly difficult. Simple search engines and basic content management are increasingly unable to effectively extract the right information from the mountains of data available. By bringing these tools into context and integrating them with business processes and applications, we can effectively focus on the right decisions that make our organizations more profitable. More Information Oracle will be exhibiting at DIA 2012 in Philadelphia on June 25-27. Stop by our booth Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} (#2825) to learn more about the advantages of a centralized ECM strategy and see the Oracle WebCenter Content solution, our 21 CFR Part 11 compliant content management platform.

    Read the article

  • Fun with Aggregates

    - by Paul White
    There are interesting things to be learned from even the simplest queries.  For example, imagine you are given the task of writing a query to list AdventureWorks product names where the product has at least one entry in the transaction history table, but fewer than ten. One possible query to meet that specification is: SELECT p.Name FROM Production.Product AS p JOIN Production.TransactionHistory AS th ON p.ProductID = th.ProductID GROUP BY p.ProductID, p.Name HAVING COUNT_BIG(*) < 10; That query correctly returns 23 rows (execution plan and data sample shown below): The execution plan looks a bit different from the written form of the query: the base tables are accessed in reverse order, and the aggregation is performed before the join.  The general idea is to read all rows from the history table, compute the count of rows grouped by ProductID, merge join the results to the Product table on ProductID, and finally filter to only return rows where the count is less than ten. This ‘fully-optimized’ plan has an estimated cost of around 0.33 units.  The reason for the quote marks there is that this plan is not quite as optimal as it could be – surely it would make sense to push the Filter down past the join too?  To answer that, let’s look at some other ways to formulate this query.  This being SQL, there are any number of ways to write logically-equivalent query specifications, so we’ll just look at a couple of interesting ones.  The first query is an attempt to reverse-engineer T-SQL from the optimized query plan shown above.  It joins the result of pre-aggregating the history table to the Product table before filtering: SELECT p.Name FROM ( SELECT th.ProductID, cnt = COUNT_BIG(*) FROM Production.TransactionHistory AS th GROUP BY th.ProductID ) AS q1 JOIN Production.Product AS p ON p.ProductID = q1.ProductID WHERE q1.cnt < 10; Perhaps a little surprisingly, we get a slightly different execution plan: The results are the same (23 rows) but this time the Filter is pushed below the join!  The optimizer chooses nested loops for the join, because the cardinality estimate for rows passing the Filter is a bit low (estimate 1 versus 23 actual), though you can force a merge join with a hint and the Filter still appears below the join.  In yet another variation, the < 10 predicate can be ‘manually pushed’ by specifying it in a HAVING clause in the “q1” sub-query instead of in the WHERE clause as written above. The reason this predicate can be pushed past the join in this query form, but not in the original formulation is simply an optimizer limitation – it does make efforts (primarily during the simplification phase) to encourage logically-equivalent query specifications to produce the same execution plan, but the implementation is not completely comprehensive. Moving on to a second example, the following query specification results from phrasing the requirement as “list the products where there exists fewer than ten correlated rows in the history table”: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) < 10 ); Unfortunately, this query produces an incorrect result (86 rows): The problem is that it lists products with no history rows, though the reasons are interesting.  The COUNT_BIG(*) in the EXISTS clause is a scalar aggregate (meaning there is no GROUP BY clause) and scalar aggregates always produce a value, even when the input is an empty set.  In the case of the COUNT aggregate, the result of aggregating the empty set is zero (the other standard aggregates produce a NULL).  To make the point really clear, let’s look at product 709, which happens to be one for which no history rows exist: -- Scalar aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709;   -- Vector aggregate SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = 709 GROUP BY th.ProductID; The estimated execution plans for these two statements are almost identical: You might expect the Stream Aggregate to have a Group By for the second statement, but this is not the case.  The query includes an equality comparison to a constant value (709), so all qualified rows are guaranteed to have the same value for ProductID and the Group By is optimized away. In fact there are some minor differences between the two plans (the first is auto-parameterized and qualifies for trivial plan, whereas the second is not auto-parameterized and requires cost-based optimization), but there is nothing to indicate that one is a scalar aggregate and the other is a vector aggregate.  This is something I would like to see exposed in show plan so I suggested it on Connect.  Anyway, the results of running the two queries show the difference at runtime: The scalar aggregate (no GROUP BY) returns a result of zero, whereas the vector aggregate (with a GROUP BY clause) returns nothing at all.  Returning to our EXISTS query, we could ‘fix’ it by changing the HAVING clause to reject rows where the scalar aggregate returns zero: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID HAVING COUNT_BIG(*) BETWEEN 1 AND 9 ); The query now returns the correct 23 rows: Unfortunately, the execution plan is less efficient now – it has an estimated cost of 0.78 compared to 0.33 for the earlier plans.  Let’s try adding a redundant GROUP BY instead of changing the HAVING clause: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY th.ProductID HAVING COUNT_BIG(*) < 10 ); Not only do we now get correct results (23 rows), this is the execution plan: I like to compare that plan to quantum physics: if you don’t find it shocking, you haven’t understood it properly :)  The simple addition of a redundant GROUP BY has resulted in the EXISTS form of the query being transformed into exactly the same optimal plan we found earlier.  What’s more, in SQL Server 2008 and later, we can replace the odd-looking GROUP BY with an explicit GROUP BY on the empty set: SELECT p.Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ); I offer that as an alternative because some people find it more intuitive (and it perhaps has more geek value too).  Whichever way you prefer, it’s rather satisfying to note that the result of the sub-query does not exist for a particular correlated value where a vector aggregate is used (the scalar COUNT aggregate always returns a value, even if zero, so it always ‘EXISTS’ regardless which ProductID is logically being evaluated). The following query forms also produce the optimal plan and correct results, so long as a vector aggregate is used (you can probably find more equivalent query forms): WHERE Clause SELECT p.Name FROM Production.Product AS p WHERE ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) < 10; APPLY SELECT p.Name FROM Production.Product AS p CROSS APPLY ( SELECT NULL FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () HAVING COUNT_BIG(*) < 10 ) AS ca (dummy); FROM Clause SELECT q1.Name FROM ( SELECT p.Name, cnt = ( SELECT COUNT_BIG(*) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID GROUP BY () ) FROM Production.Product AS p ) AS q1 WHERE q1.cnt < 10; This last example uses SUM(1) instead of COUNT and does not require a vector aggregate…you should be able to work out why :) SELECT q.Name FROM ( SELECT p.Name, cnt = ( SELECT SUM(1) FROM Production.TransactionHistory AS th WHERE th.ProductID = p.ProductID ) FROM Production.Product AS p ) AS q WHERE q.cnt < 10; The semantics of SQL aggregates are rather odd in places.  It definitely pays to get to know the rules, and to be careful to check whether your queries are using scalar or vector aggregates.  As we have seen, query plans do not show in which ‘mode’ an aggregate is running and getting it wrong can cause poor performance, wrong results, or both. © 2012 Paul White Twitter: @SQL_Kiwi email: [email protected]

    Read the article

  • Mscorlib mocking minus the attribute

    - by mehfuzh
    Mocking .net framework members (a.k.a. mscorlib) is always a daunting task. It’s the breed of static and final methods and full of surprises. Technically intercepting mscorlib members is completely different from other class libraries. This is the reason it is dealt differently. Generally, I prefer writing a wrapper around an mscorlib member (Ex. File.Delete(“abc.txt”)) and expose it via interface but that is not always an easy task if you already have years old codebase. While mocking mscorlib members first thing that comes to people’s mind is DateTime.Now. If you Google through, you will find tons of example dealing with just that. May be it’s the most important class that we can’t ignore and I will create an example using JustMock Q2 with the same. In Q2 2012, we just get rid of the MockClassAtrribute for mocking mscorlib members. JustMock is already attribute free for mocking class libraries. We radically think that vendor specific attributes only makes your code smelly and therefore decided the same for mscorlib. Now, I want to fake DateTime.Now for the following class: public class NestedDateTime { public DateTime GetDateTime() { return DateTime.Now; } } It is the simplest one that can be. The first thing here is that I tell JustMock “hey we have a DateTime.Now in NestedDateTime class that we want to mock”. To do so, during the test initialization I write this: .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Mock.Replace(() => DateTime.Now).In<NestedDateTime>(x => x.GetDateTime());.csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I can also define it for all the members in the class, but that’s just a waste of extra watts. Mock.Replace(() => DateTime.Now).In<NestedDateTime>(); Now question, why should I bother doing it? The answer is that I am not using attribute and with this approach, I can mock any framework members not just File, FileInfo or DateTime. Here to note that we already mock beyond the three but when nested around a complex class, JustMock was not intercepting it correctly. Therefore, we decided to get rid of the attribute altogether fixing the issue. Finally, I write my test as usual. [TestMethod] public void ShouldAssertMockingDateTimeFromNestedClass() { var expected = new DateTime(2000, 1, 1); Mock.Arrange(() => DateTime.Now).Returns(expected); Assert.Equal(new NestedDateTime().GetDateTime(), expected); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } That’s it, we are good. Now let me do the same for a random one, let’s say I want mock a member from DriveInfo: Mock.Replace<DriveInfo[]>(() => DriveInfo.GetDrives()).In<MsCorlibFixture>(x => x.ShouldReturnExpectedDriveWhenMocked()); Moving forward, I write my test: [TestMethod] public void ShouldReturnExpectedDriveWhenMocked() { Mock.Arrange(() => DriveInfo.GetDrives()).MustBeCalled(); DriveInfo.GetDrives(); Mock.Assert(()=> DriveInfo.GetDrives()); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here is one convention; you have to replace the mscorlib member before executing the target method that contains it. Here the call to DriveInfo is within the MsCorlibFixture therefore it should be defined during test initialization or before executing the test method. Hope this gives you the idea.

    Read the article

  • Free Document/Content Management System Using SharePoint 2010

    - by KunaalKapoor
    That’s right, it’s true. You can use the free version of SharePoint 2010 to meet your document and content management needs and even run your public facing website or an internal knowledge bank.  SharePoint Foundation 2010 is free. It may not have all the features that you get in the enterprise license but it still has enough to cater to your needs to build a document management system and replace age old file shares or folders. I’ve built a dozen content management sites for internal and public use exploiting SharePoint. There are hundreds of web content management systems out there (see CMS Matrix).  On one hand we have commercial platforms like SharePoint, SiteCore, and Ektron etc. which are the most frequently used and on the other hand there are free options like WordPress, Drupal, Joomla, and Plone etc. which are pretty common popular as well. But I would be very surprised if anyone was able to find a single CMS platform that is all things to all people. Infact not a lot of people consider SharePoint’s free version under the free CMS side but its high time organizations benefit from this. Through this blog post I wanted to present SharePoint Foundation as an option for running a FREE CMS platform. Even if you knew that there is a free version of SharePoint, what most people don’t realize is that SharePoint Foundation is a great option for running web sites of all kinds – not just team sites. It is a great option for many reasons, but in reality it is supported by Microsoft, and above all it is FREE (yay!), and it is extremely easy to get started.  From a functionality perspective – it’s hard to beat SharePoint. Even the free version, SharePoint Foundation, offers simple data connectivity (through BCS), cross browser support, accessibility, support for Office Web Apps, blogs, wikis, templates, document support, health analyzer, support for presence, and MUCH more.I often get asked: “Can I use SharePoint 2010 as a document management system?” The answer really depends on ·          What are your specific requirements? ·          What systems you currently have in place for managing documents. ·          And of course how much money you have J Benefits? Not many large organizations have benefited from SharePoint yet. For some it has been an IT project to see what they can achieve with it, for others it has been used as a collaborative platform or in many cases an extended intranet. SharePoint 2010 has changed the game slightly as the improvements that Microsoft have made have been noted by organizations, and we are seeing a lot of companies starting to build specific business applications using SharePoint as the basis, and nearly every business process will require documents at some stage. If you require a document management system and have SharePoint in place then it can be a relatively straight forward decision to use SharePoint, as long as you have reviewed the considerations just discussed. The collaborative nature of SharePoint 2010 is also a massive advantage, as specific departmental or project sites can be created quickly and easily that allow workers to interact in a variety of different ways using one source of information.  This also benefits an organization with regards to how they manage the knowledge that they have, as if all of their information is in one source then it is naturally easier to search and manage. Is SharePoint right for your organization? As just discussed, this can only be determined after defining your requirements and also planning a longer term strategy for how you will manage your documents and information. A key factor to look at is how the users would interact with the system and how much value would it get for your organization. The amount of data and documents that organizations are creating is increasing rapidly each year. Therefore the ability to archive this information, whilst keeping the ability to know what you have and where it is, is vital to any organizations management of their information life cycle. SharePoint is best used for the initial life of business documents where they need to be referenced and accessed after time. It is often beneficial to archive these to overcome for storage and performance issues. FREE CMS – SharePoint, Really? In order to show some of the completely of what comes with this free version of SharePoint 2010, I thought it would make sense to use Wikipedia (since every one trusts it as a credible source). Wikipedia shows that a web content management system typically has the following components: Document Management:   -       CMS software may provide a means of managing the life cycle of a document from initial creation time, through revisions, publication, archive, and document destruction. SharePoint is king when it comes to document management.  Version history, exclusive check-out, security, publication, workflow, and so much more.  Content Virtualization:   -       CMS software may provide a means of allowing each user to work within a virtual copy of the entire Web site, document set, and/or code base. This enables changes to multiple interdependent resources to be viewed and/or executed in-context prior to submission. Through the use of versioning, each content manager can preview, publish, and roll-back content of pages, wiki entries, blog posts, documents, or any other type of content stored in SharePoint.  The idea of each user having an entire copy of the website virtualized is a bit odd to me – not sure why anyone would need that for anything but the simplest of websites. Automated Templates:   -       Create standard output templates that can be automatically applied to new and existing content, allowing the appearance of all content to be changed from one central place. Through the use of Master Pages and Themes, SharePoint provides the ability to change the entire look and feel of site.  Of course, the older brother version of SharePoint – SharePoint Server 2010 – also introduces the concept of Page Layouts which allows page template level customization and even switching the layout of an individual page using different page templates.  I think many organizations really think they want this but rarely end up using this bit of functionality.  Easy Edits:   -       Once content is separated from the visual presentation of a site, it usually becomes much easier and quicker to edit and manipulate. Most WCMS software includes WYSIWYG editing tools allowing non-technical individuals to create and edit content. This is probably easier described with a screen cap of a vanilla SharePoint Foundation page in edit mode.  Notice the page editing toolbar, the multiple layout options…  It’s actually easier to use than Microsoft Word. Workflow management: -       Workflow is the process of creating cycles of sequential and parallel tasks that must be accomplished in the CMS. For example, a content creator can submit a story, but it is not published until the copy editor cleans it up and the editor-in-chief approves it. Workflow, it’s in there. In fact, the same workflow engine is running under SharePoint Foundation that is running under the other versions of SharePoint.  The primary difference is that with SharePoint Foundation – you need to configure the workflows yourself.   Web Standards: -       Active WCMS software usually receives regular updates that include new feature sets and keep the system up to current web standards. SharePoint is in the fourth major iteration under Microsoft with the 2010 release.  In addition to the innovation that Microsoft continuously adds, you have the entire global ecosystem available. Scalable Expansion:   -       Available in most modern WCMSs is the ability to expand a single implementation (one installation on one server) across multiple domains. SharePoint Foundation can run multiple sites using multiple URLs on a single server install.  Even more powerful, SharePoint Foundation is scalable and can be part of a multi-server farm to ensure that it will handle any amount of traffic that can be thrown at it. Delegation & Security:  -       Some CMS software allows for various user groups to have limited privileges over specific content on the website, spreading out the responsibility of content management. SharePoint Foundation provides very granular security capabilities. Read @ http://msdn.microsoft.com/en-us/library/ee537811.aspx Content Syndication:  -       CMS software often assists in content distribution by generating RSS and Atom data feeds to other systems. They may also e-mail users when updates are available as part of the workflow process. SharePoint Foundation nails it.  With RSS syndication and email alerts available out of the box, content syndication is already in the platform. Multilingual Support: -       Ability to display content in multiple languages. SharePoint Foundation 2010 supports more than 40 languages. Read More Read more @ http://msdn.microsoft.com/en-us/library/dd776256(v=office.12).aspxYou can download the free version from http://www.microsoft.com/en-us/download/details.aspx?id=5970

    Read the article

  • Disaster, or Migration?

    - by Rob Farley
    This post is in two parts – technical and personal. And I should point out that it’s prompted in part by this month’s T-SQL Tuesday, hosted by Allen Kinsel. First, the technical: I’ve had a few conversations with people recently about migration – moving a SQL Server database from one box to another (sometimes, but not primarily, involving an upgrade). One question that tends to come up is that of downtime. Obviously there will be some period of time between the old server being available and the new one. The way that most people seem to think of migration is this: Build a new server. Stop people from using the old server. Take a backup of the old server Restore it on the new server. Reconfigure the client applications (or alternatively, configure the new server to use the same address as the old) Make the new server online. There are other things involved, such as testing, of course. But this is essentially the process that people tell me they’re planning to follow. The bit that I want to look at today (as you’ve probably guessed from my title) is the “backup and restore” section. If a SQL database is using the Simple Recovery Model, then the only restore option is the last database backup. This backup could be full or differential. The transaction log never gets backed up in the Simple Recovery Model. Instead, it truncates regularly to stay small. One that’s using the Full Recovery Model (or Bulk-Logged) won’t truncate its log – the log must be backed up regularly. This provides the benefit of having a lot more option available for restores. It’s a requirement for most systems of High Availability, because if you’re making sure that a spare box is up-and-running, ready to take over, then you have to be interested in the logs that are happening on the current box, rather than truncating them all the time. A High Availability system such as Mirroring, Replication or Log Shipping will initialise the spare machine by restoring a full database backup (and maybe a differential backup if available), and then any subsequent log backups. Once the secondary copy is close, transactions can be applied to keep the two in sync. The main aspect of any High Availability system is to have a redundant system that is ready to take over. So the similarity for migration should be obvious. If you need to move a database from one box to another, then introducing a High Availability mechanism can help. By turning on the Full Recovery Model and then taking a backup (so that the now-interesting logs have some context), logs start being kept, and are therefore available for getting the new box ready (even if it’s an upgraded version). When the migration is ready to occur, a failover can be done, letting the new server take over the responsibility of the old, just as if a disaster had happened. Except that this is a planned failover, not a disaster at all. There’s a fine line between a disaster and a migration. Failovers can be useful in patching, upgrading, maintenance, and more. Hopefully, even an unexpected disaster can be seen as just another failover, and there can be an opportunity there – perhaps to get some work done on the principal server to increase robustness. And if I’ve just set up a High Availability system for even the simplest of databases, it’s not necessarily a bad thing. :) So now the personal: It’s been an interesting time recently... June has been somewhat odd. A court case with which I was involved got resolved (through mediation). I can’t go into details, but my lawyers tell me that I’m allowed to say how I feel about it. The answer is ‘lousy’. I don’t regret pursuing it as long as I did – but in the end I had to make a decision regarding the commerciality of letting it continue, and I’m going to look forward to the days when the kind of money I spent on my lawyers is small change. Mind you, if I had a similar situation with an employer, I’d do the same again, but that doesn’t really stop me feeling frustrated about it. The following day I had to fly to country Victoria to see my grandmother, who wasn’t expected to last the weekend. She’s still around a week later as I write this, but her 92-year-old body has basically given up on her. She’s been a Christian all her life, and is looking forward to eternity. We’ll all miss her though, and it’s hard to see my family grieving. Then on Tuesday, I was driving back to the airport with my family to come home, when something really bizarre happened. We were travelling down the freeway, just pulled out to go past a truck (farm-truck sized, not a semi-trailer), when a car-sized mass of metal fell off it. It was something like an industrial air-conditioner, but from where I was sitting, it was just a mass of spinning metal, like something out of a movie (one friend described it as “holidays by Michael Bay”). Somehow, and I’m really don’t know how, the part of it nearest us bounced high enough to clear the car, and there wasn’t even a scratch. We pulled over the check, and I was just thanking God that we’d changed lanes when we had, and that we remained unharmed. I had all kinds of thoughts about what could’ve happened if we’d had something that size land on the windscreen... All this has drilled home that while I feel that I haven’t provided as well for the family as I could’ve done (like by pursuing an expensive legal case), I shouldn’t even consider that I have proper control over things. I get to live life, and make decisions based on what I feel is right at the time. But I’m not going to get everything right, and there will be things that feel like disasters, some which could’ve been in my control and some which are very much beyond my control. The case feels like something I could’ve pursued differently, a disaster that could’ve been avoided in some way. Gran dying is lousy of course. An accident on the freeway would have been awful. I need to recognise that the worst disasters are ones that I can’t affect, and that I need to look at things in context – perhaps seeing everything that happens as a migration instead. Life is never the same from one day to the next. Every event has a before and an after – sometimes it’s clearly positive, sometimes it’s not. I remember good events in my life (such as my wedding), and bad (such as the loss of my father when I was ten, or the back injury I had eight years ago). I’m not suggesting that I know how to view everything from the “God works all things for good” perspective, but I am trying to look at last week as a migration of sorts. Those things are behind me now, and the future is in God’s hands. Hopefully I’ve learned things, and will be able to live accordingly. I’ve come through this time now, and even though I’ll miss Gran, I’ll see her again one day, and the future is bright.

    Read the article

  • Wear and tear on server hard drive from filesystem polling by PHP script

    - by jackie
    So I'm working on a discussion platform, and various clients will visit http://host/thread.php, which will render the discussion thread to date in addition to a form to submit a new post. When a new post is submitted, I would like all of the other clients with browser windows open to have it appear in near-real-time. One of the constraints of my script is that it may not use a DBMS and it must stay in the filesystem. Additionally, I can't use any PECL/PEAR extensions like inotify or anything like that for IPC. The flow will look like this: Client A requests thread.php and the thread is so far empty, but nonetheless it opens a Server-Side Event at eventPusher.php. Client B does the same. Client A fills out a post in the form and and submits (POSTs) it to subHandler.php. ??? (subHandler stores the new submission into the main thread storefile which gets read from when a fresh, new client requests thread.php, in addition to somehow signalling to the continually-running eventPusher event-source that a new comment was posted and that it should echo the event-json to the client. How, exactly, it will send this signal I'm yet unsure of, but there are a few options that I've thought of -- this is the crux of the question, so see below for more clarification) eventPusher.php happily pushes the new event to the client and it shows up soon after it was originally submitted on all clients who have the page open's screens. Now for the #4 missing-link mystery-step, I see a few problems. I mean, either way, eventPusher is gonna be doing a while loop of some sort -- it's gonna be polling something, I think that much is clear. (If that's a bad assumption please do let me know.) Now, the simplest way would be subHandler gets invoked on the form submission, writes it to the main store in addition to newComments.xml, then exits without doing anything else. Then eventPusher checks in newComments.xml every X seconds (by the way, what would be a reasonable time interval here?) and if it finds something then it emits an event to the client. Now, my fear with this is that the server's hard drive will have to constantly start spinning up. Maybe this isn't the case, perhaps it would just get cached in RAM and the linux kernel would take care of this transparently such that filesystem access doesn't actually engage the device because the kernel knows that that particular file hasn't changed since last read. * idea #2: I have no idea how to go about this, but perhaps there is a variable scope that gets stored in general RAM on the system which can be read by any process. Like if we mega-exported a bash variable so that $new_post is normally false but it gets toggled to true by subHandler, and then back to flase once it's pushed to the client. I doubt there's such a variable scope in PHP directly, but I struggle with the concept of variable scope, I just can't seem to understand it no matter what I read on it. * idea #3: eventPusher queries ps in its whileloop for another instance of itself. If there's not another eventPusher active then it's highly unlikely that new comments will be getting submitted. It's okay if this only works =90% of the time, it doesn't need to be completely foolproof. * idea #4: eventPusher queries DMESG to see if that file's been written to recently. So to sum everything up, I need to have inter-php-script-communication in near-real-time that will work on a standard mod_php shared hosting setup without any elevated privileges, PHP addon modules, or other system adjustments that can't be done from the PHP script itself at runtime. With*out* spinning up the drive more than a few times. No SQL servers either. Apologies if my english isn't the best, I'm still trying to improve on it.

    Read the article

  • Computer Networks UNISA - Chap 10 &ndash; In Depth TCP/IP Networking

    - by MarkPearl
    After reading this section you should be able to Understand methods of network design unique to TCP/IP networks, including subnetting, CIDR, and address translation Explain the differences between public and private TCP/IP networks Describe protocols used between mail clients and mail servers, including SMTP, POP3, and IMAP4 Employ multiple TCP/IP utilities for network discovery and troubleshooting Designing TCP/IP-Based Networks The following sections explain how network and host information in an IPv4 address can be manipulated to subdivide networks into smaller segments. Subnetting Subnetting separates a network into multiple logically defined segments, or subnets. Networks are commonly subnetted according to geographic locations, departmental boundaries, or technology types. A network administrator might separate traffic to accomplish the following… Enhance security Improve performance Simplify troubleshooting The challenges of Classful Addressing in IPv4 (No subnetting) The simplest type of IPv4 is known as classful addressing (which was the Class A, Class B & Class C network addresses). Classful addressing has the following limitations. Restriction in the number of usable IPv4 addresses (class C would be limited to 254 addresses) Difficult to separate traffic from various parts of a network Because of the above reasons, subnetting was introduced. IPv4 Subnet Masks Subnetting depends on the use of subnet masks to identify how a network is subdivided. A subnet mask indicates where network information is located in an IPv4 address. The 1 in a subnet mask indicates that corresponding bits in the IPv4 address contain network information (likewise 0 indicates the opposite) Each network class is associated with a default subnet mask… Class A = 255.0.0.0 Class B = 255.255.0.0 Class C = 255.255.255.0 An example of calculating  the network ID for a particular device with a subnet mask is shown below.. IP Address = 199.34.89.127 Subnet Mask = 255.255.255.0 Resultant Network ID = 199.34.89.0 IPv4 Subnetting Techniques Subnetting breaks the rules of classful IPv4 addressing. Read page 490 for a detailed explanation Calculating IPv4 Subnets Read page 491 – 494 for an explanation Important… Subnetting only applies to the devices internal to your network. Everything external looks at the class of the IP address instead of the subnet network ID. This way, traffic directed to your network externally still knows where to go, and once it has entered your internal network it can then be prioritized and segmented. CIDR (classless Interdomain Routing) CIDR is also known as classless routing or supernetting. In CIDR conventional network class distinctions do not exist, a subnet boundary can move to the left, therefore generating more usable IP addresses on your network. A subnet created by moving the subnet boundary to the left is known as a supernet. With CIDR also came new shorthand for denoting the position of subnet boundaries known as CIDR notation or slash notation. CIDR notation takes the form of the network ID followed by a forward slash (/) followed by the number of bits that are used for the extended network prefix. To take advantage of classless routing, your networks routers must be able to interpret IP addresses that don;t adhere to conventional network class parameters. Routers that rely on older routing protocols (i.e. RIP) are not capable of interpreting classless IP addresses. Internet Gateways Gateways are a combination of software and hardware that enable two different network segments to exchange data. A gateway facilitates communication between different networks or subnets. Because on device cannot send data directly to a device on another subnet, a gateway must intercede and hand off the information. Every device on a TCP/IP based network has a default gateway (a gateway that first interprets its outbound requests to other subnets, and then interprets its inbound requests from other subnets). The internet contains a vast number of routers and gateways. If each gateway had to track addressing information for every other gateway on the Internet, it would be overtaxed. Instead, each handles only a relatively small amount of addressing information, which it uses to forward data to another gateway that knows more about the data’s destination. The gateways that make up the internet backbone are called core gateways. Address Translation An organizations default gateway can also be used to “hide” the organizations internal IP addresses and keep them from being recognized on a public network. A public network is one that any user may access with little or no restrictions. On private networks, hiding IP addresses allows network managers more flexibility in assigning addresses. Clients behind a gateway may use any IP addressing scheme, regardless of whether it is recognized as legitimate by the Internet authorities but as soon as those devices need to go on the internet, they must have legitimate IP addresses to exchange data. When a clients transmission reaches the default gateway, the gateway opens the IP datagram and replaces the client’s private IP address with an Internet recognized IP address. This process is known as NAT (Network Address Translation). TCP/IP Mail Services All Internet mail services rely on the same principles of mail delivery, storage, and pickup, though they may use different types of software to accomplish these functions. Email servers and clients communicate through special TCP/IP application layer protocols. These protocols, all of which operate on a variety of operating systems are discussed below… SMTP (Simple Mail transfer Protocol) The protocol responsible for moving messages from one mail server to another over TCP/IP based networks. SMTP belongs to the application layer of the ODI model and relies on TCP as its transport protocol. Operates from port 25 on the SMTP server Simple sub-protocol, incapable of doing anything more than transporting mail or holding it in a queue MIME (Multipurpose Internet Mail Extensions) The standard message format specified by SMTP allows for lines that contain no more than 1000 ascii characters meaning if you relied solely on SMTP you would have very short messages and nothing like pictures included in an email. MIME us a standard for encoding and interpreting binary files, images, video, and non-ascii character sets within an email message. MIME identifies each element of a mail message according to content type. MIME does not replace SMTP but works in conjunction with it. Most modern email clients and servers support MIME POP (Post Office Protocol) POP is an application layer protocol used to retrieve messages from a mail server POP3 relies on TCP and operates over port 110 With POP3 mail is delivered and stored on a mail server until it is downloaded by a user Disadvantage of POP3 is that it typically does not allow users to save their messages on the server because of this IMAP is sometimes used IMAP (Internet Message Access Protocol) IMAP is a retrieval protocol that was developed as a more sophisticated alternative to POP3 The single biggest advantage IMAP4 has over POP3 is that users can store messages on the mail server, rather than having to continually download them Users can retrieve all or only a portion of any mail message Users can review their messages and delete them while the messages remain on the server Users can create sophisticated methods of organizing messages on the server Users can share a mailbox in a central location Disadvantages of IMAP are typically related to the fact that it requires more storage space on the server. Additional TCP/IP Utilities Nearly all TCP/IP utilities can be accessed from the command prompt on any type of server or client running TCP/IP. The syntaxt may differ depending on the OS of the client. Below is a list of additional TCP/IP utilities – research their use on your own! Ipconfig (Windows) & Ifconfig (Linux) Netstat Nbtstat Hostname, Host & Nslookup Dig (Linux) Whois (Linux) Traceroute (Tracert) Mtr (my traceroute) Route

    Read the article

< Previous Page | 38 39 40 41 42 43 44 45  | Next Page >