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  • Top YouTube Plugins for WordPress Blogs

    - by Matt
    Smart Youtube Smart Youtube allow you to insert video and playlists into your WordPress post and in your RSS feed. It is perfectly work son Works on iPhone, iPad and iPod etc and issues a sidebar widget for videos as well. WP YouTube WP YouTube act as a a profile editor, where you can set [...] Related posts:WordPress Plugins to Help Make Your Site Responsive 15 Useful SEO Plugins For WordPress The Top 10 WordPress RSS Plugins

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  • Using Gadgets Within Your Website Design

    Using these gadgets/ widgets can help to make your website very interactive for users. RSS feeds can feed into your website the latest news from all kinds of other websites such as the BBC. Twitter feeds allow your users to see your most recent tweets and this enables them to also follow you on Twitter.

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  • Some SharePoint NDA Information

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • How big can my SharePoint 2010 installation be?

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • WCF/ADO.NET Data Services - Could not load type 'System.Data.Services.Providers.IDataServiceUpdatePr

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Implementing Silverlight Coverflow with ADO.NET/WCF Data Services in SharePoint 2010

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • An access violation occurs when you run a Visual C++ application in Visual Studio 2005 SP1

    980422 ... An access violation occurs when you run a Visual C++ application in Visual Studio 2005 SP1This RSS feed provided by kbAlerz.com.Visit kbAlertz.com to subscribe. It's 100% free and you'll be able to recieve e-mail or RSS updates for the technologies you pick from the Microsoft Knowledge Base....Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Accessing SharePoint 2010 Data with REST/OData on Windows Phone 7

    - by Jan Tielens
    Consuming SharePoint 2010 data in Windows Phone 7 applications using the CTP version of the developer tools is quite a challenge. The issue is that the SharePoint 2010 data is not anonymously available; users need to authenticate to be able to access the data. When I first tried to access SharePoint 2010 data from my first Hello-World-type Windows Phone 7 application I thought “Hey, this should be easy!” because Windows Phone 7 development based on Silverlight and SharePoint 2010 has a Client Object Model for Silverlight. Unfortunately you can’t use the Client Object Model of SharePoint 2010 on the Windows Phone platform; there’s a reference to an assembly that’s not available (System.Windows.Browser). My second thought was “OK, no problem!” because SharePoint 2010 also exposes a REST/OData API to access SharePoint data. Using the REST API in SharePoint 2010 is as easy as making a web request for a URL (in which you specify the data you’d like to retrieve), e.g. http://yoursiteurl/_vti_bin/listdata.svc/Announcements. This is very easy to accomplish in a Silverlight application that’s running in the context of a page in a SharePoint site, because the credentials of the currently logged on user are automatically picked up and passed to the WCF service. But a Windows Phone application is of course running outside of the SharePoint site’s page, so the application should build credentials that have to be passed to SharePoint’s WCF service. This turns out to be a small challenge in Silverlight 3, the WebClient doesn’t support authentication; there is a Credentials property but when you set it and make the request you get a NotImplementedException exception. Probably this issued will be solved in the very near future, since Silverlight 4 does support authentication, and there’s already a WCF Data Services download that uses this new platform feature of Silverlight 4. So when Windows Phone platform switches to Silverlight 4, you can just use the WebClient to get the data. Even more, if the OData Client Library for Windows Phone 7 gets updated after that, things should get even easier! By the way: the things I’m writing in this paragraph are just assumptions that I make which make a lot of sense IMHO, I don’t have any info all of this will happen, but I really hope so. So are SharePoint developers out of the Windows Phone development game until they get this fixed? Well luckily not, when the HttpWebRequest class is being used instead, you can pass credentials! Using the HttpWebRequest class is slightly more complex than using the WebClient class, but the end result is that you have access to your precious SharePoint 2010 data. The following code snippet is getting all the announcements of an Annoucements list in a SharePoint site: HttpWebRequest webReq =     (HttpWebRequest)HttpWebRequest.Create("http://yoursite/_vti_bin/listdata.svc/Announcements");webReq.Credentials = new NetworkCredential("username", "password"); webReq.BeginGetResponse(    (result) => {        HttpWebRequest asyncReq = (HttpWebRequest)result.AsyncState;         XDocument xdoc = XDocument.Load(            ((HttpWebResponse)asyncReq.EndGetResponse(result)).GetResponseStream());         XNamespace ns = "http://www.w3.org/2005/Atom";        var items = from item in xdoc.Root.Elements(ns + "entry")                    select new { Title = item.Element(ns + "title").Value };         this.Dispatcher.BeginInvoke(() =>        {            foreach (var item in items)                MessageBox.Show(item.Title);        });    }, webReq); When you try this in a Windows Phone 7 application, make sure you add a reference to the System.Xml.Linq assembly, because the code uses Linq to XML to parse the resulting Atom feed, so the Title of every announcement is being displayed in a MessageBox. Check out my previous post if you’d like to see a more polished sample Windows Phone 7 application that displays SharePoint 2010 data.When you plan to use this technique, it’s of course a good idea to encapsulate the code doing the request, so it becomes really easy to get the data that you need. In the following code snippet you can find the GetAtomFeed method that gets the contents of any Atom feed, even if you need to authenticate to get access to the feed. delegate void GetAtomFeedCallback(Stream responseStream); public MainPage(){    InitializeComponent();     SupportedOrientations = SupportedPageOrientation.Portrait |         SupportedPageOrientation.Landscape;     string url = "http://yoursite/_vti_bin/listdata.svc/Announcements";    string username = "username";    string password = "password";    string domain = "";     GetAtomFeed(url, username, password, domain, (s) =>    {        XNamespace ns = "http://www.w3.org/2005/Atom";        XDocument xdoc = XDocument.Load(s);         var items = from item in xdoc.Root.Elements(ns + "entry")                    select new { Title = item.Element(ns + "title").Value };         this.Dispatcher.BeginInvoke(() =>        {            foreach (var item in items)            {                MessageBox.Show(item.Title);            }        });    });} private static void GetAtomFeed(string url, string username,     string password, string domain, GetAtomFeedCallback cb){    HttpWebRequest webReq = (HttpWebRequest)HttpWebRequest.Create(url);    webReq.Credentials = new NetworkCredential(username, password, domain);     webReq.BeginGetResponse(        (result) =>        {            HttpWebRequest asyncReq = (HttpWebRequest)result.AsyncState;            HttpWebResponse resp = (HttpWebResponse)asyncReq.EndGetResponse(result);            cb(resp.GetResponseStream());        }, webReq);}

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  • Demystified - BI in SharePoint 2010

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • SharePoint MVP Chat &ndash; tomorrow and day after

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • : in node causing Keyerror in xmlparsing using ElementTree

    - by kguckian
    Hi I'm using ElementTree to parse out an xml feed from Kuler. I'm only beginning in python but am stuck here. The parsing works fine until I attempt to retrieve any nodes containing ':' e.g kuler:swatchHexColor Below is a cut down version of the full feed but same structure: <rss xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:kuler="http://kuler.adobe.com/kuler/API/rss/" xmlns:rss="http://blogs.law.harvard.edu/tech/rss" version="2.0"> <channel> <title>kuler popular themes</title> <item> <title>Theme Title: Fresh Money</title> <description> &lt;img src="http://kuler-api.adobe.com/kuler/themeImages/theme_808366.png" /&gt;&lt;br /&gt; Artist: thesylph005&lt;br /&gt; ThemeID: 808366&lt;br /&gt; Posted: 03/02/2010&lt;br /&gt; Hex: 2F400D, 8CBF26, A8CA65, E8E5B0, 419184 </description> <kuler:themeItem> <kuler:themeID>808366</kuler:themeID> <kuler:themeTitle>Fresh Money</kuler:themeTitle> <kuler:themeImage>http://kuler-api.adobe.com/kuler/themeImages/theme_808366.png</kuler:themeImage> <kuler:themeAuthor> <kuler:authorID>370750</kuler:authorID> <kuler:authorLabel>thesylph005</kuler:authorLabel> </kuler:themeAuthor> <kuler:themeTags/> <kuler:themeRating>4</kuler:themeRating> <kuler:themeDownloadCount>708</kuler:themeDownloadCount> <kuler:themeCreatedAt>20100302</kuler:themeCreatedAt> <kuler:themeEditedAt>20100302</kuler:themeEditedAt> <kuler:themeSwatches> <kuler:swatch> <kuler:swatchHexColor>2F400D</kuler:swatchHexColor> <kuler:swatchColorMode>rgb</kuler:swatchColorMode> <kuler:swatchChannel1>0.183333</kuler:swatchChannel1> <kuler:swatchChannel2>0.25</kuler:swatchChannel2> <kuler:swatchChannel3>0.05</kuler:swatchChannel3> <kuler:swatchChannel4>0.0</kuler:swatchChannel4> <kuler:swatchIndex>0</kuler:swatchIndex> </kuler:swatch> <kuler:swatch> <kuler:swatchHexColor>8CBF26</kuler:swatchHexColor> <kuler:swatchColorMode>rgb</kuler:swatchColorMode> <kuler:swatchChannel1>0.55</kuler:swatchChannel1> <kuler:swatchChannel2>0.75</kuler:swatchChannel2> <kuler:swatchChannel3>0.15</kuler:swatchChannel3> <kuler:swatchChannel4>0.0</kuler:swatchChannel4> <kuler:swatchIndex>1</kuler:swatchIndex> </kuler:swatch> <kuler:swatch> <kuler:swatchHexColor>A8CA65</kuler:swatchHexColor> <kuler:swatchColorMode>rgb</kuler:swatchColorMode> <kuler:swatchChannel1>0.659722</kuler:swatchChannel1> <kuler:swatchChannel2>0.791667</kuler:swatchChannel2> <kuler:swatchChannel3>0.395833</kuler:swatchChannel3> <kuler:swatchChannel4>0.0</kuler:swatchChannel4> <kuler:swatchIndex>2</kuler:swatchIndex> </kuler:swatch> <kuler:swatch> <kuler:swatchHexColor>E8E5B0</kuler:swatchHexColor> <kuler:swatchColorMode>rgb</kuler:swatchColorMode> <kuler:swatchChannel1>0.91</kuler:swatchChannel1> <kuler:swatchChannel2>0.898047</kuler:swatchChannel2> <kuler:swatchChannel3>0.688705</kuler:swatchChannel3> <kuler:swatchChannel4>0.0</kuler:swatchChannel4> <kuler:swatchIndex>3</kuler:swatchIndex> </kuler:swatch> <kuler:swatch> <kuler:swatchHexColor>419184</kuler:swatchHexColor> <kuler:swatchColorMode>rgb</kuler:swatchColorMode> <kuler:swatchChannel1>0.254901</kuler:swatchChannel1> <kuler:swatchChannel2>0.57</kuler:swatchChannel2> <kuler:swatchChannel3>0.519034</kuler:swatchChannel3> <kuler:swatchChannel4>0.0</kuler:swatchChannel4> <kuler:swatchIndex>4</kuler:swatchIndex> </kuler:swatch> </kuler:themeSwatches> Tue, 30 Mar 2010 11:27:12 PST So if I do a findall on say each item's description, I get that back fine. But the minute I try to retrieve anything with a : in the nodename I get Exception Type: KeyError Exception Value: ':' So this works from elementtree.ElementTree import Element, SubElement, dump, parse def xml(): kulerurl = 'http://kuler-api.adobe.com/rss/get.cfm?listType=popular&startIndex=0&itemsPerPage=5&timeSpan=30&key=mykey' rss = parse(urllib.urlopen(kulerurl)).getroot() for element in rss.findall('channel/item'): print(element.findtext('description')) dump (rss) but this doesn't def xml(): kulerurl = 'http://kuler-api.adobe.com/rss/get.cfm?listType=popular&startIndex=0&itemsPerPage=5&timeSpan=30&key=mykey' rss = parse(urllib.urlopen(kulerurl)).getroot() for element in rss.findall('channel/item/kuler:themeItem'): print(element.findtext('kuler:themeID')) dump (rss) I'm sure it's something simple if anyone could point me to what I'm doing wrong here I'd be most grateful thanks Kieran

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  • Pixar Animation Techniques That Powered Movies Like Toy Story & Wall E

    - by Gopinath
    Pixar few of the worlds best animation movies like Toy Story, Cars, Wall E and A Bug Life. For those who love these movies and would like to know how Pixar makes the incredibly beautiful animations here is a two minutes video. This article titled,Pixar Animation Techniques That Powered Movies Like Toy Story & Wall E, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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  • I&rsquo;ve moved out&hellip;

    - by Michael Cummings
    Originally posted on: http://geekswithblogs.net/Mathoms/archive/2013/06/21/irsquove-moved-outhellip.aspxGeeksWithBlogs has been a great property ever since I decided to start bloggging, however I have outgrown it and am moving to a new location. Please visit me at http://michaelcummings.net from now on. The RSS feed has been updated so that should automatically update to the new address. I’ll miss GWB, but my new property is hosted on Azure using Orchard and I have been really enjoying it so far.

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  • PASS Professional Development Virtual Chapter Reboot

    - by AjarnMark
    The Professional Development Virtual Chapter for PASS is holding its first virtual meeting on Thursday, May 13 at 1:00 PM Eastern / 10:00 AM Pacfic time.  Andy Warren (@sqlandy) will be the speaker.  Click here to attend via Live Meeting.  Also, check the http://prof-dev.sqlpass.org web site and RSS Feed for ongoing updates and details.

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  • How can I verify that javascript and images are being cached?

    - by BestPractices
    I want to verify that the images, css, and javascript files that are part of my page are being cached by my browser. I've used Fiddler and Google Page Speed and it's unclear whether either is giving me the information I need. Fiddler shows the HTTP 304 response for images, css, and javascript which should tell the browser to use the cached copy. Google Page Speed shows the 304 response but doesn't show a Transfer Size of Zero, instead it shows the full file size of the resource. Note also, I have seen Google Page Speed report a 200 response but then put the word (cache) next to the 200 (so Status is 200 (cache)), which doesnt make a lot of sense. Any other suggestions as to how I can verify whether the server is sending back images, css, javascript after they've been retrieved and cached by a previous page hit?

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  • Speaking on SharePoint 2010 and Silverlight tonight

    Ad:: SharePoint 2007 Training in .NET 3.5 technologies (more information). This feed URL has been discontinued. Please update your reader's URL to : http://feeds.feedburner.com/winsmarts Read full article .... ...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Displaying a pdf file located on a http server from mobile phone

    - by JCasso
    I have some pdf files located on a http server: Like: http://domain.com/files/file1.pdf http://domain.com/files/file1.pdf http://domain.com/files/file1.pdf I need to display these files on a mobile application using java me. I tried to display them by opening Google Docs Viewer with platformRequest. However it seems Google Docs Viewer uses ajax and many mobile browsers does not support it. Is there an alternative for "Google Docs Viewer" for mobile devices ? Or is there a better solution for this problem ?

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  • wget return downloaded filename

    - by Matthew
    I'm using wget in a php script and need to get the name of the file downloaded. For example, if I try <?php system('/usr/bin/wget -q --directory-prefix="./downloads/" http://www.google.com/'); ?> I will get a file called index.html in the downloads directory. The page will not always be google though, so I need to find out the name of the file that was downloaded. I'd like to have something like this: <?php //Does not work: $filename = system('/usr/bin/wget -q --directory-prefix="./downloads/" http://www.google.com/'); //$filename should contain "index.html" ?>

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  • Facebook Threatens Greasemonkey Script Writer

    <b>TechDirt:</b> "This time, it's Facebook, which is apparently trying to bully the maker of a Greasemonkey script that cleans up your Facebook live feed by removing annoying app notices (such as all the crap your friends are doing in Farmville and Mafia Wars)."

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  • New Blog Site

    - by Miguel A. Castro
    Effective immediately, my blog is hosted on www.dotnetdude.com. This blog will no longer be updated so please check out my new one and update your RSS feed with this link. Miguel

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  • Sql simple query

    - by Josemalive
    Hello, I have the following table Persons_Companies that shows a relation between persons and companies knowns by these persons: PersonID | CompanyID 1 1 2 1 2 2 3 2 4 2 Imaging that company 1="Google" and company 2 is ="Microsoft", i would like to know the query to have the following result: PersonID | Microsoft | Google 1 0 1 2 1 1 3 1 0 4 1 0 Until this moment i have something similar: select PersonID, case when CompanyID=1 then 1 else 0 end as Google, case when EmpresaID=2 then 1 else 0 end as Microsoft from Persons_Companies My problem is with the persons that knows both companies, i cant imagine how could this query be. Could you give me a hand? Thanks in advance. Best Regards. Josema.

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  • Guide to MySQL & NoSQL, Webinar Q&A

    - by Mat Keep
    0 0 1 959 5469 Homework 45 12 6416 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} Yesterday we ran a webinar discussing the demands of next generation web services and how blending the best of relational and NoSQL technologies enables developers and architects to deliver the agility, performance and availability needed to be successful. Attendees posted a number of great questions to the MySQL developers, serving to provide additional insights into areas like auto-sharding and cross-shard JOINs, replication, performance, client libraries, etc. So I thought it would be useful to post those below, for the benefit of those unable to attend the webinar. Before getting to the Q&A, there are a couple of other resources that maybe useful to those looking at NoSQL capabilities within MySQL: - On-Demand webinar (coming soon!) - Slides used during the webinar - Guide to MySQL and NoSQL whitepaper  - MySQL Cluster demo, including NoSQL interfaces, auto-sharing, high availability, etc.  So here is the Q&A from the event  Q. Where does MySQL Cluster fit in to the CAP theorem? A. MySQL Cluster is flexible. A single Cluster will prefer consistency over availability in the presence of network partitions. A pair of Clusters can be configured to prefer availability over consistency. A full explanation can be found on the MySQL Cluster & CAP Theorem blog post.  Q. Can you configure the number of replicas? (the slide used a replication factor of 1) Yes. A cluster is configured by an .ini file. The option NoOfReplicas sets the number of originals and replicas: 1 = no data redundancy, 2 = one copy etc. Usually there's no benefit in setting it >2. Q. Interestingly most (if not all) of the NoSQL databases recommend having 3 copies of data (the replication factor).    Yes, with configurable quorum based Reads and writes. MySQL Cluster does not need a quorum of replicas online to provide service. Systems that require a quorum need > 2 replicas to be able to tolerate a single failure. Additionally, many NoSQL systems take liberal inspiration from the original GFS paper which described a 3 replica configuration. MySQL Cluster avoids the need for a quorum by using a lightweight arbitrator. You can configure more than 2 replicas, but this is a tradeoff between incrementally improved availability, and linearly increased cost. Q. Can you have cross node group JOINS? Wouldn't that run into the risk of flooding the network? MySQL Cluster 7.2 supports cross nodegroup joins. A full cross-join can require a large amount of data transfer, which may bottleneck on network bandwidth. However, for more selective joins, typically seen with OLTP and light analytic applications, cross node-group joins give a great performance boost and network bandwidth saving over having the MySQL Server perform the join. Q. Are the details of the benchmark available anywhere? According to my calculations it results in approx. 350k ops/sec per processor which is the largest number I've seen lately The details are linked from Mikael Ronstrom's blog The benchmark uses a benchmarking tool we call flexAsynch which runs parallel asynchronous transactions. It involved 100 byte reads, of 25 columns each. Regarding the per-processor ops/s, MySQL Cluster is particularly efficient in terms of throughput/node. It uses lock-free minimal copy message passing internally, and maximizes ID cache reuse. Note also that these are in-memory tables, there is no need to read anything from disk. Q. Is access control (like table) planned to be supported for NoSQL access mode? Currently we have not seen much need for full SQL-like access control (which has always been overkill for web apps and telco apps). So we have no plans, though especially with memcached it is certainly possible to turn-on connection-level access control. But specifically table level controls are not planned. Q. How is the performance of memcached APi with MySQL against memcached+MySQL or any other Object Cache like Ecache with MySQL DB? With the memcache API we generally see a memcached response in less than 1 ms. and a small cluster with one memcached server can handle tens of thousands of operations per second. Q. Can .NET can access MemcachedAPI? Yes, just use a .Net memcache client such as the enyim or BeIT memcache libraries. Q. Is the row level locking applicable when you update a column through memcached API? An update that comes through memcached uses a row lock and then releases it immediately. Memcached operations like "INCREMENT" are actually pushed down to the data nodes. In most cases the locks are not even held long enough for a network round trip. Q. Has anyone published an example using something like PHP? I am assuming that you just use the PHP memcached extension to hook into the memcached API. Is that correct? Not that I'm aware of but absolutely you can use it with php or any of the other drivers Q. For beginner we need more examples. Take a look here for a fully worked example Q. Can I access MySQL using Cobol (Open Cobol) or C and if so where can I find the coding libraries etc? A. There is a cobol implementation that works well with MySQL, but I do not think it is Open Cobol. Also there is a MySQL C client library that is a standard part of every mysql distribution Q. Is there a place to go to find help when testing and/implementing the NoSQL access? If using Cluster then you can use the [email protected] alias or post on the MySQL Cluster forum Q. Are there any white papers on this?  Yes - there is more detail in the MySQL Guide to NoSQL whitepaper If you have further questions, please don’t hesitate to use the comments below!

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  • Setting useLegacyV2RuntimeActivationPolicy At Runtime

    - by Reed
    Version 4.0 of the .NET Framework included a new CLR which is almost entirely backwards compatible with the 2.0 version of the CLR.  However, by default, mixed-mode assemblies targeting .NET 3.5sp1 and earlier will fail to load in a .NET 4 application.  Fixing this requires setting useLegacyV2RuntimeActivationPolicy in your app.Config for the application.  While there are many good reasons for this decision, there are times when this is extremely frustrating, especially when writing a library.  As such, there are (rare) times when it would be beneficial to set this in code, at runtime, as well as verify that it’s running correctly prior to receiving a FileLoadException. Typically, loading a pre-.NET 4 mixed mode assembly is handled simply by changing your app.Config file, and including the relevant attribute in the startup element: <?xml version="1.0" encoding="utf-8" ?> <configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0"/> </startup> </configuration> .csharpcode { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .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; margin: 0em; width: 100% } .csharpcode .lnum { color: #606060 } This causes your application to run correctly, and load the older, mixed-mode assembly without issues. For full details on what’s happening here and why, I recommend reading Mark Miller’s detailed explanation of this attribute and the reasoning behind it. Before I show any code, let me say: I strongly recommend using the official approach of using app.config to set this policy. That being said, there are (rare) times when, for one reason or another, changing the application configuration file is less than ideal. While this is the supported approach to handling this issue, the CLR Hosting API includes a means of setting this programmatically via the ICLRRuntimeInfo interface.  Normally, this is used if you’re hosting the CLR in a native application in order to set this, at runtime, prior to loading the assemblies.  However, the F# Samples include a nice trick showing how to load this API and bind this policy, at runtime.  This was required in order to host the Managed DirectX API, which is built against an older version of the CLR. This is fairly easy to port to C#.  Instead of a direct port, I also added a little addition – by trapping the COM exception received if unable to bind (which will occur if the 2.0 CLR is already bound), I also allow a runtime check of whether this property was setup properly: public static class RuntimePolicyHelper { public static bool LegacyV2RuntimeEnabledSuccessfully { get; private set; } static RuntimePolicyHelper() { ICLRRuntimeInfo clrRuntimeInfo = (ICLRRuntimeInfo)RuntimeEnvironment.GetRuntimeInterfaceAsObject( Guid.Empty, typeof(ICLRRuntimeInfo).GUID); try { clrRuntimeInfo.BindAsLegacyV2Runtime(); LegacyV2RuntimeEnabledSuccessfully = true; } catch (COMException) { // This occurs with an HRESULT meaning // "A different runtime was already bound to the legacy CLR version 2 activation policy." LegacyV2RuntimeEnabledSuccessfully = false; } } [ComImport] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] [Guid("BD39D1D2-BA2F-486A-89B0-B4B0CB466891")] private interface ICLRRuntimeInfo { void xGetVersionString(); void xGetRuntimeDirectory(); void xIsLoaded(); void xIsLoadable(); void xLoadErrorString(); void xLoadLibrary(); void xGetProcAddress(); void xGetInterface(); void xSetDefaultStartupFlags(); void xGetDefaultStartupFlags(); [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)] void BindAsLegacyV2Runtime(); } } Using this, it’s possible to not only set this at runtime, but also verify, prior to loading your mixed mode assembly, whether this will succeed. In my case, this was quite useful – I am working on a library purely for internal use which uses a numerical package that is supplied with both a completely managed as well as a native solver.  The native solver uses a CLR 2 mixed-mode assembly, but is dramatically faster than the pure managed approach.  By checking RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully at runtime, I can decide whether to enable the native solver, and only do so if I successfully bound this policy. There are some tricks required here – To enable this sort of fallback behavior, you must make these checks in a type that doesn’t cause the mixed mode assembly to be loaded.  In my case, this forced me to encapsulate the library I was using entirely in a separate class, perform the check, then pass through the required calls to that class.  Otherwise, the library will load before the hosting process gets enabled, which in turn will fail. This code will also, of course, try to enable the runtime policy before the first time you use this class – which typically means just before the first time you check the boolean value.  As a result, checking this early on in the application is more likely to allow it to work. Finally, if you’re using a library, this has to be called prior to the 2.0 CLR loading.  This will cause it to fail if you try to use it to enable this policy in a plugin for most third party applications that don’t have their app.config setup properly, as they will likely have already loaded the 2.0 runtime. As an example, take a simple audio player.  The code below shows how this can be used to properly, at runtime, only use the “native” API if this will succeed, and fallback (or raise a nicer exception) if this will fail: public class AudioPlayer { private IAudioEngine audioEngine; public AudioPlayer() { if (RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully) { // This will load a CLR 2 mixed mode assembly this.audioEngine = new AudioEngineNative(); } else { this.audioEngine = new AudioEngineManaged(); } } public void Play(string filename) { this.audioEngine.Play(filename); } } Now – the warning: This approach works, but I would be very hesitant to use it in public facing production code, especially for anything other than initializing your own application.  While this should work in a library, using it has a very nasty side effect: you change the runtime policy of the executing application in a way that is very hidden and non-obvious.

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

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

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