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  • Extract and convert all Excel worksheets into CSV files using PowerShell

    Can PowerShell provide an easy way to export Excel as a CSV? Yes. Tim Smith demonstrates that whether you have multiple Excel files, or just multiple worksheets in Excel, PowerShell simplifies the process. Get to grips with SQL Server replicationIn this new eBook Sebastian Meine gives a hands-on introduction to SQL Server replication, including implementation and security. Download free ebook now.

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  • Google Sitemap Limits?

    - by Anonymous -
    I've read in multiple places that Google's sitemap limits sits at 50,000 URLs per sitemap - though it's my understanding that you can submit multiple sitemaps to overcome this problem. I've also found that Google follow the sitemap protocol found here. My question is - is there anywhere where Google directly comment on the specifications and limits of sitemaps they accept? All the information I've found isn't behind any Google domain.

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  • Taking a Projects Development to the Next Level

    - by user1745022
    I have been looking for some advice for a while on how to handle a project I am working on, but to no avail. I am pretty much on my fourth iteration of improving an "application" I am working on; the first two times were in Excel, the third Time in Access, and now in Visual Studio. The field is manufacturing. The basic idea is I am taking read-only data from a massive Sybase server, filtering it and creating much smaller tables in Access daily (using delete and append Queries) and then doing a bunch of stuff. More specifically, I use a series of queries to either combine data from multiple tables or group data in specific ways (aggregate functions), and then I place this data into a table (so I can sort and manipulate data using DAO.recordset and run multiple custom algorithms). This process is then repeated multiple times throughout the database until a set of relevant tables are created. Many times I will create a field in a query with a value such as 1.1 so that when I append it to a table I can store information in the field from the algorithms. So as the process continues the number of fields for the tables change. The overall application consists of 4 "back-end" databases linked together on a shared drive, with various output (either front-end access applications or Excel). So my question is is this how many data driven applications that solve problems essentially work? Each backend database is updated with fresh data daily and updating each takes around 10 seconds (for three) and 2 minutes(for 1). Project Objectives. I want/am moving to SQL Server soon. Front End will be a Web Application (I know basic web-development and like the administration flexibility) and visual-studio will be IDE with c#/.NET. Should these algorithms be run "inside the database," or using a series of C# functions on each server request. I know you're not supposed to store data in a database unless it is an actual data point, and in Access I have many columns that just hold calculations from algorithms in vba. The truth is, I have seen multiple professional Access applications, and have never seen one that has the complexity or does even close to what mine does (for better or worse). But I know some professional software applications are 1000 times better then mine. So Please Please Please give me a suggestion of some sort. I have been completely on my own and need some guidance on how to approach this project the right way.

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  • Change reply-to in evolution

    - by ?????? ????????
    I am getting in my inbox on gmail mail from multiple addresses. When I get e-mails in gmail I can choose reply-to address. Is there such a possibility in Evolution? I know that in the advanced settings, you can specify the return address for the account, but how to make sure that there was a list of multiple addresses and be able to choose just one? Or maybe there is a possibility that at once expose the return address for letters?

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  • Labeling algorithm for points

    - by Qwertie
    I need an algorithm to place horizontal text labels for multiple series of points on the screen (basically I need to show timestamps and other information for a history of moving objects on a map; in general there are multiple data points per object). The text labels should appear close to their points--above, below, or on the right side--but should not overlap other points or text labels. Does anyone know an algorithm/heuristic for this?

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  • 2d, Top-down map with different levels

    - by Ktash
    So, I'm creating a 2d, top down, sprite based (tiled) game, and right now I'm working on maps (well, a map editor at the moment, but it will be creating my maps, so basically the same thing). The scenario So, I'm thinking about efficiency and creating a map in pieces. In each piece, I plan on having 'layers'. Basically, I plan on rendering it down to a 'below hero' level, and an 'above hero' level, with the hero rendered in between obviously. There will likely also be a 'on level with hero' layer, but I'm not quite there yet. Not even worrying about events or interaction yet. Just looking to get a hero on the screen. Now for movement, I obviously need to know what tiles can be moved and in what direction. My plan at the moment is each tile getting 8 bits (4 'can enter in direction' bits, 4 'can leave in direction'). This will allow me to limit movement and even allow one way directional movement. The dilemma This works great for a lot of scenarios. It will allow me to store a map in essentially 3 layers, a string, and gives me flexibility going forward. However, I can't create maps that themselves have layers. A good example is a bridge where the user can go under or over the bridge without invalid moves being allowed. I can't create a platform and allow movement underneath. These are things I would like to be able to include in my game. My idea In theory, I could allow multiple hero layers and then allow multiple sets of 'below' and 'above' layers (or sandwich layers). But this complicates my system, and makes movement between maps potentially tricky (If the hero is on the third layer at the edge of a map, but that corresponds to the second layer on the other map, how can I allow or disallow movement). My question Is there a better way to manage multiple maps with multiple levels like this where a users level may be 'connected' on different levels on different maps? Or even... Am I doing this the hard way? Is there a more standard way to handle top-down 2d tiled maps that I am just not aware of? Things to note or that might be helpful This will be done in Javascript (transferred around in JSON) State will need to be transferred quickly, so a map-id and x/y/direction should be enough to get me a boolean 'can move' value Maps will not be standard sized (though they will be in a certain number of tiles) Making an editor tool so that I can have others help, so something that I can create in a tool would be helpful 'Teleportation' locations will likely need to exist to get into building maps and to and from different map sets (which will not necessarily be connected), but have not been created yet (lumping in with events at the moment).

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  • Simplified Restores with SQL Server 2012 Recovery Advisor

    Occasionally, a DBA may need to restore a database from a multiple backup files that originated from multiple servers. This requirement might arise, for example, in a database-mirroring configuration, where backups may be from either of the servers. Get smart with SQL Backup ProGet faster, smaller backups with integrated verification.Quickly and easily DBCC CHECKDB your backups. Learn more.

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  • Basics of SQL Server 2008 Locking

    Relational databases are designed for multiple simultaneous users, and Microsoft SQL Server is no different. However, supporting multiple users requires some form of concurrency control, which in SQL Server's case means transaction isolation and locking. Read on to learn how SQL Server 2008 implements locking.

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  • Basics of SQL Server 2008 Locking

    Relational databases are designed for multiple simultaneous users, and Microsoft SQL Server is no different. However, supporting multiple users requires some form of concurrency control, which in SQL Server's case means transaction isolation and locking. Read on to learn how SQL Server 2008 implements locking.

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  • EF4 CTP5 Conflicting changes detected. This may happen when trying to insert multiple entities with the same key.

    - by user658332
    hi, I am new to EF4 CTP5. I am just hanging at one problem.. I am using CodeFirst without Database, so when i execute application, it generated DB for me. here is my scenario, i have following Class structure... public class KVCalculationWish { public KVCalculationWish() { } public int KVCalculationWishId { get; set; } public string KVCalculationWishName { get; set; } public int KVSingleOfferId { get; set; } public virtual KVSingleOffer SingleOffer { get; set; } public int KVCalculationsForPersonId { get; set; } public virtual KVCalculationsForPerson CaculationsForPerson { get; set; } } public class KVSingleOffer { public KVSingleOffer() { } public int KVSingleOfferId { get; set; } public string KVSingleOfferName { get; set; } public KVCalculationWish CalculationWish { get; set; } } public class KVCalculationsForPerson { public KVCalculationsForPerson() { } public int KVCalculationsForPersonId { get; set; } public string KVCalculationsForPersonName { get; set; } public KVCalculationWish CalculationWish { get; set; } } public class EntiyRelation : DbContext { public EntiyRelation() { } public DbSet<KVCalculationWish> CalculationWish { get; set; } public DbSet<KVSingleOffer> SingleOffer { get; set; } public DbSet<KVCalculationsForPerson> CalculationsForPerson { get; set; } protected override void OnModelCreating(System.Data.Entity.ModelConfiguration.ModelBuilder modelBuilder) { base.OnModelCreating(modelBuilder); modelBuilder.Entity<KVCalculationWish>().HasOptional(m => m.SingleOffer).WithRequired(p => p.CalculationWish); modelBuilder.Entity<KVCalculationWish>().HasOptional(m => m.CaculationsForPerson).WithRequired(p => p.CalculationWish); } } i want to use KVCalcuationWish object in KVCalcuationsForPerson and KVSingleOffer class. So when i am creating object of KVCalcuationForPerson and KVSingleOffer class i initialize both object with New KVCalcuationWish object. like this KVCalculationsForPerson calcPerson = new KVCalculationsForPerson(); KVCalculationWish wish = new KVCalculationWish() { CaculationsForPerson = calcPerson }; calcPerson.KVCalculationsForPersonName = "Person Name"; calcPerson.CalculationWish = wish; KVSingleOffer singleOffer = new KVSingleOffer(); KVCalculationWish wish1 = new KVCalculationWish() { SingleOffer = singleOffer }; singleOffer.KVSingleOfferName = "Offer Name"; singleOffer.CalculationWish = wish1; but my problem is when i save this records using following code try { db.CalculationsForPerson.Add(calcPerson); db.SingleOffer.Add(singleOffer); db.SaveChanges(); } catch (Exception ex) { } i can save successfully in DB, but in Table KVCalcuationWish i am not able to get the ID of SingleOffer and CalcuationsForPerson class object. Following is the data of KVCalcuationWish table. KVCalcuationWishID KVCalcuationWishName KVSingleOfferID KVCalcuationsForPersonID 1 NULL 0 0 Following is the data of KVSingleOFfer Table KVSingleOfferID KVSingleOfferName 1 Offer Name Follwing is the data of KVCalcuationsForPerson Table KVSingleOfferID KVSingleOfferName 1 Person Name I want to have following possible output in KVCalcuationWish table. KVCalcuationWishID KVCalcuationWishName KVSingleOfferID KVCalcuationsForPersonID 1 NULL 1 NULL 2 NULL NULL 1 so what i want to achieve is ...... when i am save KVSingleOffer object i want separate record to be inserted and when i save KVCalcuationsForPerson object another separate record should be save to KVCalcuationwish table. Is that possible? Sorry for long description... but i really hang on this situation... Thanks & Regards, Joyous Suhas

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  • Website. VoteUp or VoteDown Videos. How to restrict users voting multiple times?

    - by DJDonaL3000
    Im working on a website (html,css,javascript, ajax, php,mysql), and I want to restrict the number of times a particular user votes for a particular video. Its similar to the YouTube system where you can voteUp or voteDown a particular video. Each vote involves adding a row to the video.votes table, which logs the time, vote direction(up or down), the client IPaddress( using PHP: $ip = $_SERVER['REMOTE_ADDR']; ), and of course the ID of the video in question. Adding votes is as simple as; (pseudocode): Javascript:onClick( vote( a,b,c,d ) ), which passes variables to PHP insertion script via ajax, and finally we replace the voteing buttons with a "Thank You For Voting" message. THE PROBLEM: If you reload/refresh the page after voting, you can vote again, and again, and again, you get the point. MY QUESTION: How do you limit the amount of times a particular user votes for a particular video?? MY THOUGHTS: Do you use cookies, and add a new cookie with the id of the video. And check for a cookie before you insert a new vote.? OR Before you insert the vote, do you use the IPaddress and the videoID to see if this same user(IP) has voted for this same video(vidID) in the past 24hrs(mktime), and either allow or dissallow the voteInsertion based on this query? OR Do you just not care? Take the assumption that most users are sane, and have better things to do than refresh pages and vote repeatedly.?? Any suggestions or ideas welcome.

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  • Splunk is fantastically expensive: What are the alternatives?

    - by samsmith
    This has been discussed, but it has been several months, so it may be time to revisit it: Earlier discussion RE Splunk alternatives For the record, Splunk rocks. But the pricing is simply beyond what we can consider (When I spoke with Splunk today, the cost for a system to index 5gb/day of data is over $30,000.) That is more than we spend on SQL Server (by a large multiple), more than we spend on a rack of servers (by a multiple), etc. etc. The splunk sales team is correct (that for $30K we get more value and functionality than if we spend the same building our own system), but it doesn't matter. The splunk cost is simply too high (by a multiple). Soooooo, we are looking around! Is anyone out there building a splunk like system? Our basic need: Able to listen for syslog messages on multiple udp ports Able to index the incoming data in an async way Some kind of search engine Some kind of UI An API to the search engine (to embed in our console) We currently need to index 3-5gb/day, but need to be able to scale to 10gb/day or more. We do not need a lot of history (30 days is fine). We use Windows 2008 and 2003 servers. Thanks for your thoughts!

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  • Improved appointment rendering in RadScheduler for ASP.NET AJAX, Q1 2010

    Now that Q1 2010 release is out in the wild, we can sit down and discuss some of the changes we decided to make in the new release. One of them is the new appointment rendering of RadScheduler - a potentially breaking change, but a much needed one. If you have problems with your old custom skins, include the old base stylesheet along with your RadScheduler and set EnableEmbeddedBaseStylesheet=false in your RadScheduler. You can find the said base stylesheet attached to this post.   While trying to improve the performance of RadScheduler, I noticed that the number of resources slows down the rendering and overall performance considerably. This had to be expected - the images to support the appointment rounded corners (and the predefined resources) were quite large. However, I didnt take into account that all browsers keep for performance reasons their images uncompressed in memory and with the color depth of the current desktop. A simple calculation later I discovered that the appointment sprite itself is taking 25MB memory when loaded. Add 5 resources to the fray and you have 150MB memory down with a single blow. As it turns out - a sprite image is not a panacea, if it gets too big - dont be afraid to break it in two. The loading time may suffer, but your browser suffers more while rendering a 25MB monster. First I thought of undertaking the aforementioned solution - breaking the appointment sprite in two and thus reducing the two appointment sprites to mere 2MB uncompressed. Then I thought - the rounded corners are small - I can use borders and backgrounds to simulate rounded appointment borders while still keeping the same HTML structure. The gradients can be done with a single 10x50px image plus we have a gain - border colors and backgrounds can be changed on the fly.  I started with five rendering elements at first, then tried with four and finally I settled on only three elements.  Behold the new appointment rendering (quite simple really):       On the left you can see that the first container has only top and bottom borders and a background. In fact, the background isnt even needed since it will be obscured by the elements on top of it. The whole first container is only needed for the four dots that reside in the four corners of the appointment. On top of this container is another one that holds the left and right borders and slightly lighter background to create the illusion of a second lighter border beside the other two. At last on top of all others is placed the text container that also holds the top and bottom borders and the gradient background. On the right you can see the final result - Im quite happy with it and I hope you will be too. After creating the new rendering we took another step further - we decided to use alpha gradients for the resource rendering, thus supporting any color appointments with rounded corners and gradients. You can see some examples below:We plan on adding BorderColor and BackColor properties  to the ResourceStyles definitions for Q1 SP1. However with the new rendering in Q1 2010 we do support BackColor and BorderColor appointment properties - you only need to set AppointmentStyleMode=Default to keep RadScheduler from switching to Simple appointment rendering. Here is one screenshot of RadScheduler with appointments set to different colors: I hope that you will enjoy working with the new appointments in RadScheduler. RadScheduler base stylesheet 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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  • Improved appointment rendering in RadScheduler for ASP.NET AJAX, Q1 2010

    Now that Q1 2010 release is out in the wild, we can sit down and discuss some of the changes we decided to make in the new release. One of them is the new appointment rendering of RadScheduler - a potentially breaking change, but a much needed one. If you have problems with your old custom skins, include the old base stylesheet along with your RadScheduler and set EnableEmbeddedBaseStylesheet=false in your RadScheduler. You can find the said base stylesheet attached to this post.   While trying to improve the performance of RadScheduler, I noticed that the number of resources slows down the rendering and overall performance considerably. This had to be expected - the images to support the appointment rounded corners (and the predefined resources) were quite large. However, I didnt take into account that all browsers keep for performance reasons their images uncompressed in memory and with the color depth of the current desktop. A simple calculation later I discovered that the appointment sprite itself is taking 25MB memory when loaded. Add 5 resources to the fray and you have 150MB memory down with a single blow. As it turns out - a sprite image is not a panacea, if it gets too big - dont be afraid to break it in two. The loading time may suffer, but your browser suffers more while rendering a 25MB monster. First I thought of undertaking the aforementioned solution - breaking the appointment sprite in two and thus reducing the two appointment sprites to mere 2MB uncompressed. Then I thought - the rounded corners are small - I can use borders and backgrounds to simulate rounded appointment borders while still keeping the same HTML structure. The gradients can be done with a single 10x50px image plus we have a gain - border colors and backgrounds can be changed on the fly.  I started with five rendering elements at first, then tried with four and finally I settled on only three elements.  Behold the new appointment rendering (quite simple really):       On the left you can see that the first container has only top and bottom borders and a background. In fact, the background isnt even needed since it will be obscured by the elements on top of it. The whole first container is only needed for the four dots that reside in the four corners of the appointment. On top of this container is another one that holds the left and right borders and slightly lighter background to create the illusion of a second lighter border beside the other two. At last on top of all others is placed the text container that also holds the top and bottom borders and the gradient background. On the right you can see the final result - Im quite happy with it and I hope you will be too. After creating the new rendering we took another step further - we decided to use alpha gradients for the resource rendering, thus supporting any color appointments with rounded corners and gradients. You can see some examples below:We plan on adding BorderColor and BackColor properties  to the ResourceStyles definitions for Q1 SP1. However with the new rendering in Q1 2010 we do support BackColor and BorderColor appointment properties - you only need to set AppointmentStyleMode=Default to keep RadScheduler from switching to Simple appointment rendering. Here is one screenshot of RadScheduler with appointments set to different colors: I hope that you will enjoy working with the new appointments in RadScheduler. RadScheduler base stylesheet 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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  • Feb 2nd Links: Visual Studio, ASP.NET, ASP.NET MVC, JQuery, Windows Phone

    - by ScottGu
    Here is the latest in my link-listing series.  Also check out my Best of 2010 Summary for links to 100+ other posts I’ve done in the last year. [I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Community News MVCConf Conference Next Wednesday: Attend the free, online ASP.NET MVC Conference being organized by the community next Wednesday.  Here is a list of some of the talks you can watch live. Visual Studio HTML5 and CSS3 in VS 2010 SP1: Good post from the Visual Studio web tools team that talks about the new support coming in VS 2010 SP1 for HTML5 and CSS3. Database Deployment with the VS 2010 Package/Publish Database Tool: Rachel Appel has a nice post that covers how to enable database deployment using the built-in VS 2010 web deployment support.  Also check out her ASP.NET web deployment post from last month. VsVim Update Released: Jared posts about the latest update of his VsVim extension for Visual Studio 2010.  This free extension enables VIM based key-bindings within VS. ASP.NET How to Add Mobile Pages to your ASP.NET Web Forms / MVC Apps: Great whitepaper by Steve Sanderson that covers how to mobile-enable your ASP.NET and ASP.NET MVC based applications. New Entity Framework Tutorials for ASP.NET Developers: The ASP.NET and EF teams have put together a bunch of nice tutorials on using the Entity Framework data library with ASP.NET Web Forms. Using ASP.NET Dynamic Data with EF Code First (via NuGet): Nice post from David Ebbo that talks about how to use the new EF Code First Library with ASP.NET Dynamic Data. Common Performance Issues with ASP.NET Web Sites: Good post with lots of performance tuning suggestions (mostly deployment settings) for ASP.NET apps. ASP.NET MVC Razor View Converter: Free, automated tool from Terlik that can convert existing .aspx view templates to Razor view templates. ASP.NET MVC 3 Internationalization: Nadeem has a great post that talks about a variety of techniques you can use to enable Globalization and Localization within your ASP.NET MVC 3 applications. ASP.NET MVC 3 Tutorials by David Hayden: Great set of tutorials and posts by David Hayden on some of the new ASP.NET MVC 3 features. EF Fixed Concurrency Mode and MVC: Chris Sells has a nice post that talks about how to handle concurrency with updates done with EF using ASP.NET MVC. ASP.NET and jQuery jQuery Performance Tips and Tricks: A free 30 minute video that covers some great tips and tricks to keep in mind when using jQuery. jQuery 1.5’s AJAX rewrite and ASP.NET services - All is well: Nice post by Dave Ward that talks about using the new jQuery 1.5 to call ASP.NET ASMX Services. Good news according to Dave is that all is well :-) jQuery UI Modal Dialogs for ASP.NET MVC: Nice post by Rob Regan that talks about a few approaches you can use to implement dialogs with jQuery UI and ASP.NET MVC.  Windows Phone 7 Free PDF eBook on Building Windows Phone 7 Applications with Silverlight: Free book that walksthrough how to use Silverlight and Visual Studio to build Windows Phone 7 applications. Hope this helps, Scott

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  • User Productivity Kit - Powerful Packages (Part 2)

    - by [email protected]
    In my first post on packages I described what a package is and how it can be used. I also started explaining some of the considerations that should be taken into account when determining how to arrange your packages. The first is when the files are interrelated and depend on one another such as an HTML file and it's graphics. A second consideration is how the files are used in your outlines. Let's say you're using a dozen Word doc files. You could place them all in a single package or put each Word doc file in a separate package but what's the right thing to do? There are several factors that will influence your decision. To understand the first, let me explain a function of UPK publishing. Take an outline in UPK that has an attachment (concept, frame link, or hyperlink) that points to a file in a package. When you publish this outline, the publishing engine will determine that there is a link to a file in the package and copy the contents of the package to the publishing destination directory. This is done to ensure that any interrelated files are kept together. For the situation where you have an HTML file with links to number of graphics files, this is a good thing. If, however, the package has a dozen unrelated Word doc files and you link to only one of them, all dozen Word documents will be copied to the publishing destination directory.  Whether or not this is a good thing is dependent on two things. First, are all of the files in the package used in the outline that you're publishing? Take an outline that includes links to all of the Word documents in that dozen document package I described earlier. For this situation, you may choose to keep all the files in a single package for convenience. A second consideration is how your organization leverages reuse in UPK. In this context, I'm referring to the link style of reuse such as when you link to the same topic from multiple UPK outlines and changes to the topic appear in both places. Take an example where you have the earlier mentioned dozen Word document package and an outline with a dozen topics in it. Each topic has an attachment pointing to one of the Word documents in the package (frame link, concept, etc.) If you're only publishing this outline, the single package probably works fine but what if you're reusing one of these topics in another outline? As I explained earlier, linking to one file in the package will result in all files in the package being copied to your published output. In this example, linking to one topic in the first outline will result in all dozen Word documents being copied to the published output. This may result in files in the output that you don't want there for business or size reasons. This is a situation in which you should consider placing each of the Word documents in it's own separate package. With each document in it's own package, that link to a single document will result in only that single package and single Word document being copied to the published output. In my last post I had described that packages are documents in the UPK library. When using the multi-user version of the UPK Developer you can leverage standard library capabilities for managing the files in these packages during the development process - capabilities such as check in / check out, history, etc. When structuring your packages take into consideration how the authors are going to be adding, modifying and deleting files from the packages. A single package is a single document in the UPK library. Like any other document in the library, a single user can check out the package and edit it at a time. If you have a large number of files in a single package and these must be modified by many users, you need to consider whether this will cause problems as multiple users compete to update the same package. If the files don't depend on each other consider placing the files in separate packages to reduce contention. I hope you've enjoyed these two posts on how you can leverage the power of packages in your content. In summary, consider the following when structuring your packages: Is the asset a single, standalone file or a set of files that depend on each other? Will all the files always be used together in a single outline or may only some of the files be needed based on how the content is reused across multiple outlines? Will multiple developers need to update the files in a single package or should you break it into multiple packages to reduce contention when checking out the document? We'd like to hear from you on how you're using packages in your content. Please add your comments below! Thank you and I hope these two posts have given you additional insights into how to use packages in your content and structure them for efficient use. John Zaums Senior Director, Product Development Oracle User Productivity Kit

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  • Availability Best Practices on Oracle VM Server for SPARC

    - by jsavit
    This is the first of a series of blog posts on configuring Oracle VM Server for SPARC (also called Logical Domains) for availability. This series will show how to how to plan for availability, improve serviceability, avoid single points of failure, and provide resiliency against hardware and software failures. Availability is a broad topic that has filled entire books, so these posts will focus on aspects specifically related to Oracle VM Server for SPARC. The goal is to improve Reliability, Availability and Serviceability (RAS): An article defining RAS can be found here. Oracle VM Server for SPARC Principles for Availability Let's state some guiding principles for availability that apply to Oracle VM Server for SPARC: Avoid Single Points Of Failure (SPOFs). Systems should be configured so a component failure does not result in a loss of application service. The general method to avoid SPOFs is to provide redundancy so service can continue without interruption if a component fails. For a critical application there may be multiple levels of redundancy so multiple failures can be tolerated. Oracle VM Server for SPARC makes it possible to configure systems that avoid SPOFs. Configure for availability at a level of resource and effort consistent with business needs. Effort and resource should be consistent with business requirements. Production has different availability requirements than test/development, so it's worth expending resources to provide higher availability. Even within the category of production there may be different levels of criticality, outage tolerances, recovery and repair time requirements. Keep in mind that a simple design may be more understandable and effective than a complex design that attempts to "do everything". Design for availability at the appropriate tier or level of the platform stack. Availability can be provided in the application, in the database, or in the virtualization, hardware and network layers they depend on - or using a combination of all of them. It may not be necessary to engineer resilient virtualization for stateless web applications applications where availability is provided by a network load balancer, or for enterprise applications like Oracle Real Application Clusters (RAC) and WebLogic that provide their own resiliency. It's (often) the same architecture whether virtual or not: For example, providing resiliency against a lost device path or failing disk media is done for the same reasons and may use the same design whether in a domain or not. It's (often) the same technique whether using domains or not: Many configuration steps are the same. For example, configuring IPMP or creating a redundant ZFS pool is pretty much the same within the guest whether you're in a guest domain or not. There are configuration steps and choices for provisioning the guest with the virtual network and disk devices, which we will discuss. Sometimes it is different using domains: There are new resources to configure. Most notable is the use of alternate service domains, which provides resiliency in case of a domain failure, and also permits improved serviceability via "rolling upgrades". This is an important differentiator between Oracle VM Server for SPARC and traditional virtual machine environments where all virtual I/O is provided by a monolithic infrastructure that itself is a SPOF. Alternate service domains are widely used to provide resiliency in production logical domains environments. Some things are done via logical domains commands, and some are done in the guest: For example, with Oracle VM Server for SPARC we provide multiple network connections to the guest, and then configure network resiliency in the guest via IP Multi Pathing (IPMP) - essentially the same as for non-virtual systems. On the other hand, we configure virtual disk availability in the virtualization layer, and the guest sees an already-resilient disk without being aware of the details. These blogs will discuss configuration details like this. Live migration is not "high availability" in the sense of "continuous availability": If the server is down, then you don't live migrate from it! (A cluster or VM restart elsewhere would be used). However, live migration can be part of the RAS (Reliability, Availability, Serviceability) picture by improving Serviceability - you can move running domains off of a box before planned service or maintenance. The blog Best Practices - Live Migration on Oracle VM Server for SPARC discusses this. Topics Here are some of the topics that will be covered: Network availability using IP Multipathing and aggregates Disk path availability using virtual disks defined with multipath groups ("mpgroup") Disk media resiliency configuring for redundant disks that can tolerate media loss Multiple service domains - this is probably the most significant item and the one most specific to Oracle VM Server for SPARC. It is very widely deployed in production environments as the means to provide network and disk availability, but it can be confusing. Subsequent articles will describe why and how to configure multiple service domains. Note, for the sake of precision: an I/O domain is any domain that has a physical I/O resource (such as a PCIe bus root complex). A service domain is a domain providing virtual device services to other domains; it is almost always an I/O domain too (so it can have something to serve). Resources Here are some important links; we'll be drawing on their content in the next several articles: Oracle VM Server for SPARC Documentation Maximizing Application Reliability and Availability with SPARC T5 Servers whitepaper by Gary Combs Maximizing Application Reliability and Availability with the SPARC M5-32 Server whitepaper by Gary Combs Summary Oracle VM Server for SPARC offers features that can be used to provide highly-available environments. This and the following blog entries will describe how to plan and deploy them.

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  • "Imprinting" as a language feature?

    - by MKO
    Idea I had this idea for a language feature that I think would be useful, does anyone know of a language that implements something like this? The idea is that besides inheritance a class can also use something called "imprinting" (for lack of better term). A class can imprint one or several (non-abstract) classes. When a class imprints another class it gets all it's properties and all it's methods. It's like the class storing an instance of the imprinted class and redirecting it's methods/properties to it. A class that imprints another class therefore by definition also implements all it's interfaces and it's abstract class. So what's the point? Well, inheritance and polymorphism is hard to get right. Often composition gives far more flexibility. Multiple inheritance offers a slew of different problems without much benefits (IMO). I often write adapter classes (in C#) by implementing some interface and passing along the actual methods/properties to an encapsulated object. The downside to that approach is that if the interface changes the class breaks. You also you have to put in a lot of code that does nothing but pass things along to the encapsulated object. A classic example is that you have some class that implements IEnumerable or IList and contains an internal class it uses. With this technique things would be much easier Example (c#) [imprint List<Person> as peopleList] public class People : PersonBase { public void SomeMethod() { DoSomething(this.Count); //Count is from List } } //Now People can be treated as an List<Person> People people = new People(); foreach(Person person in people) { ... } peopleList is an alias/variablename (of your choice)used internally to alias the instance but can be skipped if not needed. One thing that's useful is to override an imprinted method, that could be achieved with the ordinary override syntax public override void Add(Person person) { DoSomething(); personList.Add(person); } note that the above is functional equivalent (and could be rewritten by the compiler) to: public class People : PersonBase , IList<Person> { private List<Person> personList = new List<Person>(); public override void Add(object obj) { this.personList.Add(obj) } public override int IndexOf(object obj) { return personList.IndexOf(obj) } //etc etc for each signature in the interface } only if IList changes your class will break. IList won't change but an interface that you, someone in your team, or a thirdparty has designed might just change. Also this saves you writing a whole lot of code for some interfaces/abstract classes. Caveats There's a couple of gotchas. First we, syntax must be added to call the imprinted classes's constructors from the imprinting class constructor. Also, what happends if a class imprints two classes which have the same method? In that case the compiler would detect it and force the class to define an override of that method (where you could chose if you wanted to call either imprinted class or both) So what do you think, would it be useful, any caveats? It seems it would be pretty straightforward to implement something like that in the C# language but I might be missing something :) Sidenote - Why is this different from multiple inheritance Ok, so some people have asked about this. Why is this different from multiple inheritance and why not multiple inheritance. In C# methods are either virtual or not. Say that we have ClassB who inherits from ClassA. ClassA has the methods MethodA and MethodB. ClassB overrides MethodA but not MethodB. Now say that MethodB has a call to MethodA. if MethodA is virtual it will call the implementation that ClassB has, if not it will use the base class, ClassA's MethodA and you'll end up wondering why your class doesn't work as it should. By the terminology sofar you might already confused. So what happens if ClassB inherits both from ClassA and another ClassC. I bet both programmers and compilers will be scratching their heads. The benefit of this approach IMO is that the imprinting classes are totally encapsulated and need not be designed with multiple inheritance in mind. You can basically imprint anything.

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  • Disabling the right-click sub menu using JQuery

    - by nikolaosk
    Recently I needed to disable the right-click contextual menu in an HTML page for a very simple HTML application I was creating for a friend.This is going to be a short post where I will demonstrate how to disable the right-click contextual menu.I will use the very popular JQuery Library. Please download the library (minified version) from http://jquery.com/downloadPlease find here all my posts regarding JQuery.In this hands-on example I will be using Expression Web 4.0.This application is not a free application. You can use any HTML editor you like.You can use Visual Studio 2012 Express edition. You can download it here. I am going to create a very simple HTML 5 page with some text and an image. The HTML markup for the page follows. <!DOCTYPE html><html lang="en">  <head>    <title>HTML 5, CSS3 and JQuery</title>        <meta http-equiv="Content-Type" content="text/html;charset=utf-8" >    <link rel="stylesheet" type="text/css" href="style.css">     <script type="text/javascript" src="jquery-1.8.2.min.js">        </script><script type="text/javascript"> (function ($) { $(document).bind('contextmenu', function () { return false;}); })(jQuery); </script>       </head>  <body>      <div id="header">      <h1>Learn cutting edge technologies</h1>      <h2>HTML 5, JQuery, CSS3</h2>    </div>      <figure>  <img src="html5.png" alt="HTML 5"></figure>        <div id="main">          <h2>HTML 5</h2>                        <article>          <p>            HTML5 is the latest version of HTML and XHTML. The HTML standard defines a single language that can be written in HTML and XML. It attempts to solve issues found in previous iterations of HTML and addresses the needs of Web Applications, an area previously not adequately covered by HTML.          </p>          </article>      </div>             </body>  </html> This is the JQuery code, I use (function ($) { $(document).bind('contextmenu', function () { return false;}); })(jQuery); I simply disable/cancel the contextmenu event.When I load the simple page on the browser and I right-click the context menu does not appear.Hope it helps!!!

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  • CSS sliding door background image problem.

    - by ethyreal
    I noticed I am not the first to ask about CSS sliding doors. However this seems (at least to me) to be a rather odd problem which I have not seen an answer for. Trying to create a simple rounded corner link button: html: <a href="#" class="link_button"><span>Add A New Somthing</span></a> css: .link_button { background: transparent url('img/backgrounds/bg-buttonRight.png') no-repeat scroll top right; color: #444; display: block; float: left; font: normal 12px arial; height: 41px; margin-right: 6px; padding-right: 14px; text-decoration: none; } .link_button span { background: transparent url('img/backgrounds/bg-buttonLeft.png') no-repeat top left; display: block; line-height: 31px; padding: 5px 0 5px 14px; } .link_button:active { background-position: bottom right; color: #000; outline: none; } .link_button:active span { background-position: bottom left; padding: 6px 0 4px 18px; } results: The two images are overlapping, which is what I want, but why the discoloration? Why would one be darker? I tried using png jpg, gif, with and without transparency. I posted the code here, along with another attempt using only one jpg instead of two, but still the same results. Did I miss something? Thanks in advance.

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  • jquery select elements between two elements that are not siblings

    - by naugtur
    eg. [I've removed attributes, but it's a bit of auto-generated html] <img class="p"/> <div> hello world <p> <font><font size="2">text.<img class="p"/> some text</font></font> </p> <img class="p"/> <p> <font><font size="2">more text<img class="p"/> another piece of text </font></font> </p><img class="p"/> some text on the end </div> I need to apply some highlighting with backgrounds to all text that is between two closest [in the html code] img.p elements when hovering first of them. I have no idea how to do that. Lets say I hover the first img.p - it should highlight hello world and text. and nothing else. And now the worst part - I need the backgrounds to disappear on mouseleave. I need it to work with any HTML mess possible. The above is just an example and structure of the documents will differ. [tip. Processing the whole html before binding hover and putting some spans etc. is ok as long as it doesn't change the looks of the output document]

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  • What are the best practices for writing maintainable CSS?

    - by Art
    I am just starting to explore this area and wonder what are the best practices when it comes to production of clean, well-structured and maintainable CSSes. There seems to be few different approaches to structuring CSS rules. One of the most commonly encountered ones I saw was throwing everything together in one rule, i.e. margins, borders, typefaces, backgrounds, something like this: .my-class { border-top:1px solid #c9d7f1; font-size:1px; font-weight:normal; height:0; position:absolute; top:24px; width:100%; } Another approach I noticed employed grouping of properties, say text-related properties like font-size, typeface, emphasis etc goes into one rule, backgrounds go into other, borders/margins go into yet another one: .my-class { border-top:1px solid #c9d7f1; } .my-class { font-size:1px; font-weight:normal; } .my-class { height:0; top:24px; width:100%; position:absolute; } I guess I am looking for a silver bullet here which I know I am not going to get, bet nevertheless - what are the best practices in this space?

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  • How Are These Styles Cascading?

    - by user1569275
    Problem is viewable at this link. http://dansdemos.info/prototypes/htmlSamples/responsive/step08_megaGridForward.html The three boxes need to have green backgrounds, but another style is taking precedence. I thought styles were supposed to take precedence based on where they appear in the style sheets, with styles lower in the style sheet cascading (taking precedence) over styles higher in the style sheet. I guess that is wrong, because the style sheet for the background colors of those boxes is here: #maincontent .col { background: #ccc; background: rgba(204, 204, 204, 0.85); } #callout1 { background-color: #00B300; text-align:center; } #callout2 { background-color: #00CC00; text-align:center; } #callout3 { background-color: #00E600; text-align:center; } When the style for "#maincontent .col" is removed, the green shows up (link)http://dansdemos.info/prototypes/htmlSamples/responsive/step08_megaGridForwardGreen.html, but I thought the green should show up because it is after the gray color specified higher up. I am finding a way to get what I need, but it would really make it a lot easier if I understood why the backgrounds are gray, instead of green. Any assistance would be extremely much appreciated. Thank you.

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  • When should I use Areas in TFS instead of Team Projects

    - by Martin Hinshelwood
    Well, it depends…. If you are a small company that creates a finite number of internal projects then you will find it easier to create a single project for each of your products and have TFS do the heavy lifting with reporting, SharePoint sites and Version Control. But what if you are not… Update 9th March 2010 Michael Fourie gave me some feedback which I have integrated. Ed Blankenship via @edblankenship offered encouragement and a nice quote. Ewald Hofman gave me a couple of Cons, and maybe a few more soon. Ewald’s company, Avanade, currently uses Areas, but it looks like the manual management is getting too much and the project is getting cluttered. What if you are likely to have hundreds of projects, possibly with a multitude of internal and external projects? You might have 1 project for a customer or 10. This is the situation that most consultancies find themselves in and thus they need a more sustainable and maintainable option. What I am advocating is that we should have 1 “Team Project” per customer, and use areas to create “sub projects” within that single “Team Project”. "What you describe is what we generally do internally and what we recommend. We make very heavy use of area path to categorize the work within a larger project." - Brian Harry, Microsoft Technical Fellow & Product Unit Manager for Team Foundation Server   "We tend to use areas to segregate multiple projects in the same team project and it works well." - Tiago Pascoal, Visual Studio ALM MVP   "In general, I believe this approach provides consistency [to multi-product engagements] and lowers the administration and maintenance costs. All good." - Michael Fourie, Visual Studio ALM MVP   “@MrHinsh BTW, I'm very much a fan of very large, if not huge, team projects in TFS. Just FYI :) Use Areas & Iterations.” Ed Blankenship, Visual Studio ALM MVP   This would mean that SSW would have a single Team Project called “SSW” that contains all of our internal projects and consequently all of the Areas and Iteration move down one hierarchy to accommodate this. Where we would have had “\SSW\Sprint 1” we now have “\SSW\SqlDeploy\Sprint1” with “SqlDeploy” being our internal project. At the moment SSW has over 70 internal projects and more than 170 total projects in TFS. This method has long term benefits that help to simplify the support model for companies that often have limited internal support time and many projects. But, there are implications as TFS does not provide this model “out-of-the-box”. These implications stretch across Areas, Iterations, Queries, Project Portal and Version Control. Michael made a good comment, he said: I agree with your approach, assuming that in a multi-product engagement with a client, they are happy to adopt the same process template across all products. If they are not, then it’ll either be easy to convince them or there is a valid reason for having a different template - Michael Fourie, Visual Studio ALM MVP   At SSW we have a standard template that we use and this is applied across the board, to all of our projects. We even apply any changes to the core process template to all of our existing projects as well. If you have multiple projects for the same clients on multiple templates and you want to keep it that way, then this approach will not work for you. However, if you want to standardise as we have at SSW then this approach may benefit you as well. Implications around Areas Areas should be used for topological classification/isolation of work items. You can think of this as architecture areas, organisational areas or even the main features of your application. In our scenario there is an additional top level item that represents the Project / Product that we want to chop our Team Project into. Figure: Creating a sub area to represent a product/project is easy. <teamproject> <teamproject>\<Functional Area/module whatever> Becomes: <teamproject> <teamproject>\<ProjectName>\ <teamproject>\<ProjectName>\<Functional Area/module whatever> Implications around Iterations Iterations should be used for chronological classification/isolation of work items. This could include isolated time boxes, milestones or release timelines and really depends on the logical flow of your project or projects. Due to the new level in Area we need to add the same level to Iteration. This is primarily because it is unlikely that the sprints in each of your projects/products will start and end at the same time. This is just a reality of managing multiple projects. Figure: Adding the same Area value to Iteration as the top level item adds flexibility to Iteration. <teamproject>\Sprint 1 Or <teamproject>\Release 1\Sprint 1 Becomes: <teamproject>\<ProjectName>\Sprint 1 Or <teamproject>\<ProjectName>\Release 1\Sprint 1 Implications around Queries Queries are used to filter your work items based on a specified level of granularity. There are a number of queries that are built into a project created using the MSF Agile 5.0 template, but we now have multiple projects and it would be a pain to have to edit all of the work items every time we changed project, and that would only allow one team to work on one project at a time.   Figure: The Queries that are created in a normal MSF Agile 5.0 project do not quite suit our new needs. In order for project contributors to be able to query based on their project we need a couple of things. The first thing I did was to create an “_Area Template” folder that has a copy of the project layout with all the queries setup to filter based on the “_Area Template” Area and the “_Sprint template” you can see in the Area and Iteration views. Figure: The template is currently easily drag and drop, but you then need to edit the queries to point at the right Area and Iteration. This needs a tool. I then created an “Areas” folder to hold all of the area specific queries. So, when you go to create a new TFS Sub-Project you just drag “_Area Template” while holding “Ctrl” and drop it onto “Areas”. There is a little setup here. That said I managed it in around 10 minutes which is not so bad, and I can imagine it being quite easy to build a tool to create these queries Figure: These new queries can be configured in around 10 minutes, which includes setting up the Area and Iteration as well. Version Control What about your source code? Well, that is the easiest of the lot. Just create a sub folder for each of your projects/products.   Figure: Creating sub folders in source control is easy as “Right click | Create new folder”. <teamproject>\DEV\Main\ Becomes: <teamproject>\<ProjectName>\DEV\Main\ Conclusion I think it is up to each company to make a call on how you want to configure your Team Projects and it depends completely on how many projects/products you are going to have for each customer including yourself. If we decide to utilise this route it will require some configuration to get our 170+ projects into this format, and I will probably be writing some tools to help. Pros You only have one project to upgrade when a process template changes – After going through an upgrade of over 170 project prior to the changes in the RC I can tell you that that many projects is no fun. Standardises your Process Template – You will always have the same Process implementation across projects/products without exception You get tighter control over the permissions – Yes, you can do this on a standard Team Project, but it gets a lot easier with practice. You can “move” work items from one “product” to another – Have we not always wanted to do that. You can rename your projects – Wahoo: everyone wants to do this, now you can. One set of Reporting Services reports to manage – You set an area and iteration to run reports anyway, so you may as well set both. Simplified Check-In Policies– There is only one set of check-in policies per client. This simplifies administration of policies. Simplified Alerts – As alerts are applied across multiple projects this simplifies your alert rules as per client. Cons All of these cons could be mitigated by a custom tool that helps automate creation of “Sub-projects” within Team Projects. This custom tool could create areas, Iteration, permissions, SharePoint and queries. It just does not exist yet :) You need to configure the Areas and Iterations You need to configure the permissions You may need to configure sub sites for SharePoint (depends on your requirement) – If you have two projects/products in the same Team Project then you will not see the burn down for each one out-of-the-box, but rather a cumulative for the Team Project. This is not really that much of a problem as you would have to configure your burndown graphs for your current iteration anyway. note: When you create a sub site to a TFS linked portal it will inherit the settings of its parent site :) This is fantastic as it means that you can easily create sub sites and then set the Area and Iteration path in each of the reports to be the correct one. Every team wants their own customization (via Ewald Hofman) - small teams of 2 persons against teams of 30 – or even outsourcing – need their own process, you cannot allow that because everybody gets the same work item types. note: Luckily at SSW this is not a problem as our template is standardised across all projects and customers. Large list of builds (via Ewald Hofman) – As the build list in Team Explorer is just a flat list it can get very cluttered. note: I would mitigate this by removing any build that has not been run in over 30 days. The build template and workflow will still be available in version control, but it will clean the list. Feedback Now that I have explained this method, what do you think? What other pros and cons can you see? What do you think of this approach? Will you be using it? What tools would you like to support you?   Technorati Tags: Visual Studio ALM,TFS Administration,TFS,Team Foundation Server,Project Planning,TFS Customisation

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  • Transactional Messaging in the Windows Azure Service Bus

    - by Alan Smith
    Introduction I’m currently working on broadening the content in the Windows Azure Service Bus Developer Guide. One of the features I have been looking at over the past week is the support for transactional messaging. When using the direct programming model and the WCF interface some, but not all, messaging operations can participate in transactions. This allows developers to improve the reliability of messaging systems. There are some limitations in the transactional model, transactions can only include one top level messaging entity (such as a queue or topic, subscriptions are no top level entities), and transactions cannot include other systems, such as databases. As the transaction model is currently not well documented I have had to figure out how things work through experimentation, with some help from the development team to confirm any questions I had. Hopefully I’ve got the content mostly correct, I will update the content in the e-book if I find any errors or improvements that can be made (any feedback would be very welcome). I’ve not had a chance to look into the code for transactions and asynchronous operations, maybe that would make a nice challenge lab for my Windows Azure Service Bus course. Transactional Messaging Messaging entities in the Windows Azure Service Bus provide support for participation in transactions. This allows developers to perform several messaging operations within a transactional scope, and ensure that all the actions are committed or, if there is a failure, none of the actions are committed. There are a number of scenarios where the use of transactions can increase the reliability of messaging systems. Using TransactionScope In .NET the TransactionScope class can be used to perform a series of actions in a transaction. The using declaration is typically used de define the scope of the transaction. Any transactional operations that are contained within the scope can be committed by calling the Complete method. If the Complete method is not called, any transactional methods in the scope will not commit.   // Create a transactional scope. using (TransactionScope scope = new TransactionScope()) {     // Do something.       // Do something else.       // Commit the transaction.     scope.Complete(); }     In order for methods to participate in the transaction, they must provide support for transactional operations. Database and message queue operations typically provide support for transactions. Transactions in Brokered Messaging Transaction support in Service Bus Brokered Messaging allows message operations to be performed within a transactional scope; however there are some limitations around what operations can be performed within the transaction. In the current release, only one top level messaging entity, such as a queue or topic can participate in a transaction, and the transaction cannot include any other transaction resource managers, making transactions spanning a messaging entity and a database not possible. When sending messages, the send operations can participate in a transaction allowing multiple messages to be sent within a transactional scope. This allows for “all or nothing” delivery of a series of messages to a single queue or topic. When receiving messages, messages that are received in the peek-lock receive mode can be completed, deadlettered or deferred within a transactional scope. In the current release the Abandon method will not participate in a transaction. The same restrictions of only one top level messaging entity applies here, so the Complete method can be called transitionally on messages received from the same queue, or messages received from one or more subscriptions in the same topic. Sending Multiple Messages in a Transaction A transactional scope can be used to send multiple messages to a queue or topic. This will ensure that all the messages will be enqueued or, if the transaction fails to commit, no messages will be enqueued.     An example of the code used to send 10 messages to a queue as a single transaction from a console application is shown below.   QueueClient queueClient = messagingFactory.CreateQueueClient(Queue1);   Console.Write("Sending");   // Create a transaction scope. using (TransactionScope scope = new TransactionScope()) {     for (int i = 0; i < 10; i++)     {         // Send a message         BrokeredMessage msg = new BrokeredMessage("Message: " + i);         queueClient.Send(msg);         Console.Write(".");     }     Console.WriteLine("Done!");     Console.WriteLine();       // Should we commit the transaction?     Console.WriteLine("Commit send 10 messages? (yes or no)");     string reply = Console.ReadLine();     if (reply.ToLower().Equals("yes"))     {         // Commit the transaction.         scope.Complete();     } } Console.WriteLine(); messagingFactory.Close();     The transaction scope is used to wrap the sending of 10 messages. Once the messages have been sent the user has the option to either commit the transaction or abandon the transaction. If the user enters “yes”, the Complete method is called on the scope, which will commit the transaction and result in the messages being enqueued. If the user enters anything other than “yes”, the transaction will not commit, and the messages will not be enqueued. Receiving Multiple Messages in a Transaction The receiving of multiple messages is another scenario where the use of transactions can improve reliability. When receiving a group of messages that are related together, maybe in the same message session, it is possible to receive the messages in the peek-lock receive mode, and then complete, defer, or deadletter the messages in one transaction. (In the current version of Service Bus, abandon is not transactional.)   The following code shows how this can be achieved. using (TransactionScope scope = new TransactionScope()) {       while (true)     {         // Receive a message.         BrokeredMessage msg = q1Client.Receive(TimeSpan.FromSeconds(1));         if (msg != null)         {             // Wrote message body and complete message.             string text = msg.GetBody<string>();             Console.WriteLine("Received: " + text);             msg.Complete();         }         else         {             break;         }     }     Console.WriteLine();       // Should we commit?     Console.WriteLine("Commit receive? (yes or no)");     string reply = Console.ReadLine();     if (reply.ToLower().Equals("yes"))     {         // Commit the transaction.         scope.Complete();     }     Console.WriteLine(); }     Note that if there are a large number of messages to be received, there will be a chance that the transaction may time out before it can be committed. It is possible to specify a longer timeout when the transaction is created, but It may be better to receive and commit smaller amounts of messages within the transaction. It is also possible to complete, defer, or deadletter messages received from more than one subscription, as long as all the subscriptions are contained in the same topic. As subscriptions are not top level messaging entities this scenarios will work. The following code shows how this can be achieved. try {     using (TransactionScope scope = new TransactionScope())     {         // Receive one message from each subscription.         BrokeredMessage msg1 = subscriptionClient1.Receive();         BrokeredMessage msg2 = subscriptionClient2.Receive();           // Complete the message receives.         msg1.Complete();         msg2.Complete();           Console.WriteLine("Msg1: " + msg1.GetBody<string>());         Console.WriteLine("Msg2: " + msg2.GetBody<string>());           // Commit the transaction.         scope.Complete();     } } catch (Exception ex) {     Console.WriteLine(ex.Message); }     Unsupported Scenarios The restriction of only one top level messaging entity being able to participate in a transaction makes some useful scenarios unsupported. As the Windows Azure Service Bus is under continuous development and new releases are expected to be frequent it is possible that this restriction may not be present in future releases. The first is the scenario where messages are to be routed to two different systems. The following code attempts to do this.   try {     // Create a transaction scope.     using (TransactionScope scope = new TransactionScope())     {         BrokeredMessage msg1 = new BrokeredMessage("Message1");         BrokeredMessage msg2 = new BrokeredMessage("Message2");           // Send a message to Queue1         Console.WriteLine("Sending Message1");         queue1Client.Send(msg1);           // Send a message to Queue2         Console.WriteLine("Sending Message2");         queue2Client.Send(msg2);           // Commit the transaction.         Console.WriteLine("Committing transaction...");         scope.Complete();     } } catch (Exception ex) {     Console.WriteLine(ex.Message); }     The results of running the code are shown below. When attempting to send a message to the second queue the following exception is thrown: No active Transaction was found for ID '35ad2495-ee8a-4956-bbad-eb4fedf4a96e:1'. The Transaction may have timed out or attempted to span multiple top-level entities such as Queue or Topic. The server Transaction timeout is: 00:01:00..TrackingId:947b8c4b-7754-4044-b91b-4a959c3f9192_3_3,TimeStamp:3/29/2012 7:47:32 AM.   Another scenario where transactional support could be useful is when forwarding messages from one queue to another queue. This would also involve more than one top level messaging entity, and is therefore not supported.   Another scenario that developers may wish to implement is performing transactions across messaging entities and other transactional systems, such as an on-premise database. In the current release this is not supported.   Workarounds for Unsupported Scenarios There are some techniques that developers can use to work around the one top level entity limitation of transactions. When sending two messages to two systems, topics and subscriptions can be used. If the same message is to be sent to two destinations then the subscriptions would have the default subscriptions, and the client would only send one message. If two different messages are to be sent, then filters on the subscriptions can route the messages to the appropriate destination. The client can then send the two messages to the topic in the same transaction.   In scenarios where a message needs to be received and then forwarded to another system within the same transaction topics and subscriptions can also be used. A message can be received from a subscription, and then sent to a topic within the same transaction. As a topic is a top level messaging entity, and a subscription is not, this scenario will work.

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