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  • Easy remote communication without WCF

    - by Ralf Westphal
    If you´ve read my previous posts about why I deem WCF more of a problem than a solution and how I think we should switch to asynchronous only communication in distributed application, you might be wondering, how this could be done in an easy way. Since a truely simple example to get started with WCF still is drawing quite some traffic to this blog, let me pick up on that and show you, how to accomplish the same but much easier with an async communication API. For simplicities sake let me put all...(read more)

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  • How to Create a Vacation Away Message for (Almost) Any Email Account

    - by Taylor Gibb
    If you are heading out of town, you might want to put a note on your email to let people know where to contact you. Or just to let them know to contact somebody else while you’re away. Here’s how to setup a vacation responder for (almost) any email account. How to See What Web Sites Your Computer is Secretly Connecting To HTG Explains: When Do You Need to Update Your Drivers? How to Make the Kindle Fire Silk Browser *Actually* Fast!

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  • Simple Mouse Move Event in F# with Winforms

    - by MarkPearl
    This evening I had the pleasure of reading one of ThomasP’s blog posts on first class events. It was an excellent read, and I thought I would make a brief derivative of his post to explore some of the basics. In Thomas’s post he has a form with an ellipse on it that when he clicks on the ellipse it pops up a message box with the button clicked… awesome. Something that got me on the post though was the code similar to the one below… // React to Mouse Move events on the form let evtMessages = frm.MouseMove |> Event.map (fun mi -> mi.Location.ToString()) |> Event.map (sprintf "Hey, you clicked on the ellipse.\nUsing: %s") |> Event.add (MessageBox.Show >> ignore) The MessageBox is a function with a string passed into it. What if I wanted to rather change a mutable value holder instead, how would the syntax go for that? Immediately the thought came to me of anonymous functions. I’ve used them before to do something like this… let HelloPerson personName = "Hello " + personName |> fun(x) -> Console.WriteLine(x) So using the same approach I adapted the event code to instead of showing a Message Box with a string passed in to it, to rather change the forms header. |> Event.map (sprintf "Your mouse position is %s") |> Event.add(fun(x) -> frm.Text <- x) Okay… it looks a bit weird with the –> x <- syntax, but makes sense and works… The next thing I wanted to do was change Thomas’s code sample from having an ellipse, and reacting to the position of the mouse and click, to rather trigger the event whenever the mouse moved. This simple involved removing some filtering code. Finally I wanted the code to work as a FSharp Project without having to run through the F# interactive. To achieve this I just needed to find out how to trigger the window event loop. This can be achieved with the code below… // Program eventloop while frm.Created do Application.DoEvents()   So lets look at the complete code sample… #light open System open System.Drawing open System.Windows.Forms // Create the main form let frm = new Form(ClientSize=Size(600,400)) // React to Mouse Move events on the form let evtMessages = frm.MouseMove |> Event.map (fun mi -> mi.Location.ToString()) |> Event.map (sprintf "Your mouse position is %s") |> Event.add(fun(x) -> frm.Text <- x) // Show the form frm.Show() // Program eventloop while frm.Created do Application.DoEvents()

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  • Neo4J and Azure and VS2012 and Windows 8

    - by Chris Skardon
    Now, I know that this has been written about, but both of the main places (http://www.richard-banks.org/2011/02/running-neo4j-on-azure.html and http://blog.neo4j.org/2011/02/announcing-neo4j-on-windows-azure.html) utilise VS2010, and well, I’m on VS2012 and Windows 8. Not that I think Win 8 had anything to do with it really, anyhews! I’m going to begin from the beginning, this is my first foray into running something on Azure, so it’s been a bit of a learning curve. But luckily the Neo4J guys have got us started, so let’s download the VS2010 solution: http://neo4j.org/get?file=Neo4j.Azure.Server.zip OK, the other thing we’ll need is the VS2012 Azure SDK, so let’s get that as well: http://www.windowsazure.com/en-us/develop/downloads/ (I just did the full install). Now, unzip the VS2010 solution and let’s open it in VS2012: <your location>\Neo4j.Azure.Server\Neo4j.Azure.Server.sln One-way-upgrade? Yer! Ignore the migration report – we don’t care! Let’s build that sucker… Ahhh 14 errors… WindowsAzure does not exist in the namespace ‘Microsoft’ Not a problem right? We’ve installed the SDK, just need to update the references: We can ignore the Test projects, they don’t use Azure, we’re interested in the other projects, so what we’ll do is remove the broken references, and add the correct ones, so expand the references bit of each project: hunt out those yellow exclamation marks, and delete them! You’ll need to add the right ones back in (listed below), when you go to the ‘Add Reference’ dialog make sure you have ‘Assemblies’ and ‘Framework’ selected before you seach (and search for ‘microsoft.win’ to narrow it down) So the references you need for each project are: CollectDiagnosticsData Microsoft.WindowsAzure.Diagnostics Microsoft.WindowsAzure.StorageClient Diversify.WindowsAzure.ServiceRuntime Microsoft.WindowsAzure.CloudDrive Microsoft.WindowsAzure.ServiceRuntime Microsoft.WindowsAzure.StorageClient Right, so let’s build again… Sweet! No errors.   Now we need to setup our Blobs, I’m assuming you are using the most up-to-date Java you happened to have downloaded :) in my case that’s JRE7, and that is located in: C:\Program Files (x86)\Java\jre7 So, zip up that folder into whatever you want to call it, I went with jre7.zip, and stuck it in a temp folder for now. In that same temp folder I also copied the neo4j zip I was using: neo4j-community-1.7.2-windows.zip OK, now, we need to get these into our Blob storage, this is where a lot of stuff becomes unstuck - I didn’t find any applications that helped me use the blob storage, one would crash (because my internet speed is so slow) and the other just didn’t work – sure it looked like it had worked, but when push came to shove it didn’t. So this is how I got my files into Blob (local first): 1. Run the ‘Storage Emulator’ (just search for that in the start menu) 2. That takes a little while to start up so fire up another instance of Visual Studio in the mean time, and create a new Console Application. 3. Manage Nuget Packages for that solution and add ‘Windows Azure Storage’ Now you’re set up to add the code: public static void Main() { CloudStorageAccount cloudStorageAccount = CloudStorageAccount.DevelopmentStorageAccount; CloudBlobClient client = cloudStorageAccount.CreateCloudBlobClient(); client.Timeout = TimeSpan.FromMinutes(30); CloudBlobContainer container = client.GetContainerReference("neo4j"); //This will create it as well   UploadBlob(container, "jre7.zip", "c:\\temp\\jre7.zip"); UploadBlob(container, "neo4j-community-1.7.2-windows.zip", "c:\\temp\\neo4j-community-1.7.2-windows.zip"); }   private static void UploadBlob(CloudBlobContainer container, string blobName, string filename) { CloudBlob blob = container.GetBlobReference(blobName);   using (FileStream fileStream = File.OpenRead(filename)) blob.UploadFromStream(fileStream); } This will upload the files to your local storage account (to switch to an Azure one, you’ll need to create a storage account, and use those credentials when you make your CloudStorageAccount above) To test you’ve got them uploaded correctly, go to: http://localhost:10000/devstoreaccount1/neo4j/jre7.zip and you will hopefully download the zip file you just uploaded. Now that those files are there, we are ready for some final configuration… Right click on the Neo4jServerHost role in the Neo4j.Azure.Server cloud project: Click on the ‘Settings’ tab and we’ll need to do some changes – by default, the 1.7.2 edition of neo4J unzips to: neo4j-community-1.7.2 So, we need to update all the ‘neo4j-1.3.M02’ directories to be ‘neo4j-community-1.7.2’, we also need to update the Java runtime location, so we start with this: and end with this: Now, I also changed the Endpoints settings, to be HTTP (from TCP) and to have a port of 7410 (mainly because that’s straight down on the numpad) The last ‘gotcha’ is some hard coded consts, which had me looking for ages, they are in the ‘ConfigSettings’ class of the ‘Neo4jServerHost’ project, and the ones we’re interested in are: Neo4jFileName JavaZipFileName Change those both to what that should be. OK Nearly there (I promise)! Run the ‘Compute Emulator’ (same deal with the Start menu), in your system tray you should have an Azure icon, when the compute emulator is up and running, right click on the icon and select ‘Show Compute Emulator UI’ The last steps! Make sure the ‘Neo4j.Azure.Server’ cloud project is set up as the start project and let’s hit F5 tension mounts, the build takes place (you need to accept the UAC warning) and VS does it’s stuff. If you look at the Compute Emulator UI you’ll see some log stuff (which you’ll need if this goes awry – but it won’t don’t worry!) In a bit, the console and a Java window will pop up: Then the console will bog off, leaving just the Java one, and if we switch back to the Compute Emulator UI and scroll up we should be able to see a line telling us the port number we’ve been assigned (in my case 7411): (If you can’t see it, don’t worry.. press CTRL+A on the emulator, then CTRL+C, copy all the text and paste it into something like Notepad, then just do a Find for ‘port’ you’ll soon see it) Go to your favourite browser, and head to: http://localhost:YOURPORT/ and you should see the WebAdmin! See you on the cloud side hopefully! Chris PS Other gotchas! OK, I’ve been caught out a couple of times: I had an instance of Neo4J running as a service on my machine, the Azure instance wanted to run the https version of the server on the same port as the Service was running on, and so Java would complain that the port was already in use.. The first time I converted the project, it didn’t update the version of the Azure library to load, in the App.Config of the Neo4jServerHost project, and VS would throw an exception saying it couldn’t find the Azure dll version 1.0.0.0.

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  • Mutable Records in F#

    - by MarkPearl
    I’m loving my expert F# book – today I thought I would give a post on using mutable records as covered in Chapter 4 of Expert F#. So as they explain the simplest mutable data structures in F# are mutable records. The whole concept of things by default being immutable is a new one for me from my C# background. Anyhow… lets look at some C# code first. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace MutableRecords { public class DiscreteEventCounter { public int Total { get; set; } public int Positive { get; set; } public string Name { get; private set; } public DiscreteEventCounter(string name) { Name = name; } } class Program { private static void recordEvent(DiscreteEventCounter s, bool isPositive) { s.Total += 1; if (isPositive) s.Positive += 1; } private static void reportStatus (DiscreteEventCounter s) { Console.WriteLine("We have {0} {1} out of {2}", s.Positive, s.Name, s.Total); } static void Main(string[] args) { var longCounter = new DiscreteEventCounter("My Discrete Counter"); recordEvent(longCounter, true); recordEvent(longCounter, true); reportStatus(longCounter); Console.ReadLine(); } } } Quite simple, we have a class that has a few values. We instantiate an instance of the class and perform increments etc on the instance. Now lets look at an equivalent F# sample. namespace EncapsulationNS module Module1 = open System type DiscreteEventCounter = { mutable Total : int mutable Positive : int Name : string } let recordEvent (s: DiscreteEventCounter) isPositive = s.Total <- s.Total+1 if isPositive then s.Positive <- s.Positive+1 let reportStatus (s: DiscreteEventCounter) = printfn "We have %d %s out of %d" s.Positive s.Name s.Total let newCounter nm = { Total = 0; Positive = 0; Name = nm } // // Using it... // let longCounter = newCounter "My Discrete Counter" recordEvent longCounter (true) recordEvent longCounter (true) reportStatus longCounter System.Console.ReadLine() Notice in the type declaration of the DiscreteEventCounter we had to explicitly declare that the total and positive value holders were mutable. And that’s it – a very simple example of mutable types.

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  • Optimizing Transaction Log Throughput

    As a DBA, it is vital to manage transaction log growth explicitly, rather than let SQL Server auto-growth events "manage" it for you. If you undersize the log, and then let SQL Server auto-grow it in small increments, you'll end up with a very fragmented log. Examples in the article, extracted from SQL Server Transaction Log Management by Tony Davis and Gail Shaw, demonstrate how this can have a significant impact on the performance of any SQL Server operations that need to read the log.

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  • Which is better for search engines, repeated phrases or different phrases with the same meaning?

    - by George Botros
    When I'm designing an ads website I have two options: Let the advertiser to choose from some predefined lists to create the new ad. For Example: product list ( T-Shirt, Shorts, Suit, .....) Color list ( Black, Red, .....) Let the advertiser to write his own descriptive content for the product For Example "Amazing suit with a good price" I like the first Scenario but which is better for search engine optimization [SEO], repeated phrases or different phrases with the same meaning? Note : assuming each page will contain one or more ads

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  • F# Project Euler Problem 1

    - by MarkPearl
    Every now and then I give project Euler a quick browse. Since I have been playing with F# I have found it a great way to learn the basics of the language. Today I thought I would give problem 1 an attempt… Problem 1 If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. My F# Solution I broke this problem into two functions… 1) be able to generate a collection of numbers that are multiples of a number but but are smaller than another number. let GenerateMultiplesOfXbelowY X Y = X |> Seq.unfold (fun i -> if (i<Y) then Some(i, i+X) else None) I then needed something that generated collections for multiples of 3 & 5 and then removed any duplicates. Once this was done I would need to sum these all together to get a result. I found the Seq object to be extremely useful to achieve this… let Multiples = Seq.append (GenerateMultiplesOfXbelowY 3 1000) (GenerateMultiplesOfXbelowY 5 1000) |> Seq.distinct |> Seq.fold(fun acc a -> acc + a) 0 |> Console.WriteLine |> Console.ReadLine My complete solution was … open System let GenerateMultiplesOfXbelowY X Y = X |> Seq.unfold (fun i -> if (i<Y) then Some(i, i+X) else None) let Multiples = Seq.append (GenerateMultiplesOfXbelowY 3 1000) (GenerateMultiplesOfXbelowY 5 1000) |> Seq.distinct |> Seq.fold(fun acc a -> acc + a) 0 |> Console.WriteLine |> Console.ReadLine   Which seemed to generate the correct result in a relatively short period of time although I am sure I will get some comments from the experts who know of some intrinsic method to achieve all of this in one method call.

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  • Advantages of Steam Greenlight

    - by ashes999
    Let's assume that I can pick a fairly decent game, build it, and finish it with sufficient chrome plating; let's also assume that I can market it myself to some extent, through my own website. What exactly are the advantages of going through Steam Greenlight? Assuming I can actually get through the process and reach sufficient critical mass to be "Greenlight." Can I really expect a lot more marketing (and sales) if I succeed?

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  • How far should an entity take care of its properties values by itself?

    - by Kharlos Dominguez
    Let's consider the following example of a class, which is an entity that I'm using through Entity Framework. - InvoiceHeader - BilledAmount (property, decimal) - PaidAmount (property, decimal) - Balance (property, decimal) I'm trying to find the best approach to keep Balance updated, based on the values of the two other properties (BilledAmount and PaidAmount). I'm torn between two practices here: Updating the balance amount every time BilledAmount and PaidAmount are updated (through their setters) Having a UpdateBalance() method that the callers would run on the object when appropriate. I am aware that I can just calculate the Balance in its getter. However, it isn't really possible because this is an entity field that needs to be saved back to the database, where it has an actual column, and where the calculated amount should be persisted to. My other worry about the automatically updating approach is that the calculated values might be a little bit different from what was originally saved to the database, due to rounding values (an older version of the software, was using floats, but now decimals). So, loading, let's say 2000 entities from the database could change their status and make the ORM believe that they have changed and be persisted back to the database the next time the SaveChanges() method is called on the context. It would trigger a mass of updates that I am not really interested in, or could cause problems, if the calculation methods changed (the entities fetched would lose their old values to be replaced by freshly recalculated ones, simply by being loaded). Then, let's take the example even further. Each invoice has some related invoice details, which also have BilledAmount, PaidAmount and Balance (I'm simplifying my actual business case for the sake of the example, so let's assume the customer can pay each item of the invoice separately rather than as a whole). If we consider the entity should take care of itself, any change of the child details should cause the Invoice totals to change as well. In a fully automated approach, a simple implementation would be looping through each detail of the invoice to recalculate the header totals, every time one the property changes. It probably would be fine for just a record, but if a lot of entities were fetched at once, it could create a significant overhead, as it would perform this process every time a new invoice detail record is fetched. Possibly worse, if the details are not already loaded, it could cause the ORM to lazy-load them, just to recalculate the balances. So far, I went with the Update() method-way, mainly for the reasons I explained above, but I wonder if it was right. I'm noticing I have to keep calling these methods quite often and at different places in my code and it is potential source of bugs. It also has a detrimental effect on data-binding because when the properties of the detail or header changes, the other properties are left out of date and the method has no way to be called. What is the recommended approach in this case?

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  • Not index page that doesn't have relevant content?

    - by Stuck
    I have a large software website and on each application we let users add comments, reviews and so on. Each of these pages are called for example "Comments About Firefox", "Firefox Reviews" and so on. If we don't have any reviews or we for some reason KNOW that the visitor from Google would be disappointed should we add "noindex" to that page? Or should we just let Google decide if they want to rank us or not?

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  • Optimizing Transaction Log Throughput

    As a DBA, it is vital to manage transaction log growth explicitly, rather than let SQL Server auto-growth events "manage" it for you. If you undersize the log, and then let SQL Server auto-grow it in small increments, you'll end up with a very fragmented log. This article demonstrates how this can have a significant impact on the performance of any SQL Server operations that need to read the log.

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  • How many java, c# companies in the US? [closed]

    - by bharal
    I was sitting around wondering - is there some way to get a reasonable estimate of the number of java-based companies in, say, the US? And then rolling with that, what about c#? (and so on) let's argue that a company can be both java and c# based - in fact, let's modify it to read "companies that could reasonably hire an xyz developer" Finally, would it be possible to organise this answer in terms of rough size of the companies? "startups" vs established?

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  • What keeps you from changing your public IP address and wreak havok?

    - by Whitemage
    An interesting question was asked to me and I did not know what to answer.. So I'll ask here. Let's say I subscribed to an ISP and I'm using cable internet access. ISP gives me a public IP address of 60.61.62.63. What keeps me from changing this IP address to, let's say, 60.61.62.75 and mess with another consumer's internet access? For the sake of this argument, let's say that this other IP address is also owned by the same ISP. Also, let's assume that it's possible for me to go into the cable modem settings and manually change the IP address. Under a business contract where you are allocated static addresses, you are also assigned a default gaetway, a network address and a broadcast address. So that's 3 addresses the ISP "loses" to you. That seems very wastefull for dynamically assigned IP addresses where the majority of customers are.. Could they simply be using static arps? ACLs? Other simple mechanisms? Anyone who worked at an ISP would be willing to explain this a bit?

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  • SQL SERVER – Spatial Database Queries – What About BLOB – T-SQL Tuesday #006

    - by pinaldave
    Michael Coles is one of the most interesting book authors I have ever met. He has a flair of writing complex stuff in a simple language. There are a very few people like that.  I really enjoyed reading his recent book, Expert SQL Server 2008 Encryption. I strongly suggest taking a look at it. This blog is written in response to T-SQL Tuesday #006: “What About BLOB? by Michael Coles. Spatial Database is my favorite subject. Since I did my TechEd India 2010 presentation, I have enjoyed this subject a lot. Before I continue this blog post, there are a few other blog posts, so I suggest you read them.  To help build the environment run the queries, I am going to present them in this single blog post. SQL SERVER – What is Spatial Database? – Developing with SQL Server Spatial and Deep Dive into Spatial Indexing This blog post explains the basics of Spatial Database and also provides a good introduction to Indexing concept. SQL SERVER – World Shapefile Download and Upload to Database – Spatial Database This blog post will enable you with how to load the shape file into database. SQL SERVER – Spatial Database Definition and Research Documents This blog post links to the white paper about Spatial Database written by Microsoft experts. SQL SERVER – Introduction to Spatial Coordinate Systems: Flat Maps for a Round Planet This blog post links to the white paper explaining coordinate system, as written by Microsoft experts. After reading the above listed blog posts, I am very confident that you are ready to run the following script. Once you create a database using the World Shapefile, as mentioned in the second link above,you can display the image of India just like the following. Please note that this is not an accurate political map. The boundary of this map has many errors and it is just a representation. You can run the following query to generate the map of India from the database spatial which you have created after following the instructions here. USE Spatial GO -- India Map SELECT [CountryName] ,[BorderAsGeometry] ,[Border] FROM [Spatial].[dbo].[Countries] WHERE Countryname = 'India' GO Now, let us find the longitude and latitude of the two major IT cities of India, Hyderabad and Bangalore. I find their values as the following: the values of longitude-latitude for Bangalore is 77.5833300000 13.0000000000; for Hyderabad, longitude-latitude is 78.4675900000 17.4531200000. Now, let us try to put these values on the India Map and see their location. -- Bangalore DECLARE @GeoLocation GEOGRAPHY SET @GeoLocation = GEOGRAPHY::STPointFromText('POINT(77.5833300000 13.0000000000)',4326).STBuffer(20000); -- Hyderabad DECLARE @GeoLocation1 GEOGRAPHY SET @GeoLocation1 = GEOGRAPHY::STPointFromText('POINT(78.4675900000 17.4531200000)',4326).STBuffer(20000); -- Bangalore and Hyderabad on Map of India SELECT name, [GeoLocation] FROM [IndiaGeoNames] I WHERE I.[GeoLocation].STDistance(@GeoLocation) <= 0 UNION ALL SELECT name, [GeoLocation] FROM [IndiaGeoNames] I WHERE I.[GeoLocation].STDistance(@GeoLocation1) <= 0 UNION ALL SELECT '',[Border] FROM [Spatial].[dbo].[Countries] WHERE Countryname = 'India' GO Now let us quickly draw a straight line between them. DECLARE @GeoLocation GEOGRAPHY SET @GeoLocation = GEOGRAPHY::STPointFromText('POINT(78.4675900000 17.4531200000)',4326).STBuffer(10000); DECLARE @GeoLocation1 GEOGRAPHY SET @GeoLocation1 = GEOGRAPHY::STPointFromText('POINT(77.5833300000 13.0000000000)',4326).STBuffer(10000); DECLARE @GeoLocation2 GEOGRAPHY SET @GeoLocation2 = GEOGRAPHY::STGeomFromText('LINESTRING(78.4675900000 17.4531200000, 77.5833300000 13.0000000000)',4326) SELECT name, [GeoLocation] FROM [IndiaGeoNames] I WHERE I.[GeoLocation].STDistance(@GeoLocation) <= 0 UNION ALL SELECT name, [GeoLocation] FROM [IndiaGeoNames] I1 WHERE I1.[GeoLocation].STDistance(@GeoLocation1) <= 0 UNION ALL SELECT '' name, @GeoLocation2 UNION ALL SELECT '',[Border] FROM [Spatial].[dbo].[Countries] WHERE Countryname = 'India' GO Let us use the distance function of the spatial database and find the straight line distance between this two cities. -- Distance Between Hyderabad and Bangalore DECLARE @GeoLocation GEOGRAPHY SET @GeoLocation = GEOGRAPHY::STPointFromText('POINT(78.4675900000 17.4531200000)',4326) DECLARE @GeoLocation1 GEOGRAPHY SET @GeoLocation1 = GEOGRAPHY::STPointFromText('POINT(77.5833300000 13.0000000000)',4326) SELECT @GeoLocation.STDistance(@GeoLocation1)/1000 'KM'; GO The result of above query is as displayed in following image. As per SQL Server, the distance between these two cities is 501 KM, but according to what I know, the distance between those two cities is around 562 KM by road. However, please note that roads are not straight and they have lots of turns, whereas this is a straight-line distance. What would be more accurate is the distance between these two cities by air travel. When we look at the air travel distance between Bangalore and Hyderabad, the total distance covered is 495 KM, which is very close to what SQL Server has estimated, which is 501 KM. Bravo! SQL Server has accurately provided the distance between two of the cities. SQL Server Spatial Database can be very useful simply because it is very easy to use, as demonstrated above. I appreciate your comments, so let me know what your thoughts and opinions about this are. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database

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  • SQL SERVER – Service Broker and CAP_CPU_PERCENT – Limiting SQL Server Instances to CPU Usage

    - by pinaldave
    I have mentioned several times on this blog that the best part of blogging is the questions I receive from readers. They are often very interesting. The questions from readers give me a good idea what other readers might be thinking as well. After reading my earlier article Simple Example to Configure Resource Governor – Introduction to Resource Governor – I received an email from a reader and we exchanged a few emails. After exchanging emails we both figured out what is going on. It was indeed interesting and reader suggested to that I should blog about it.  I asked for permission to publish his name but he does not like the attention so we will just call him Jeff. I have converted our emails into chat for easy consumption. Jeff: Your script does not work at all. I think either there is a bug in SQL Server. Pinal: Would you please explain in detail? Jeff: Your code does not limit the CPU usage? Pinal: How did you measure it? Jeff: Well, we have third party tools for it but let us say I have limited the resources for Reporting Services and used your script described in your blog. After that I ran only reporting service workload the CPU is still used more than 100% and it is not limited to 30% as described in your script. Clearly something is wrong somewhere. Pinal: Did you say you ONLY ran reporting server load? Jeff: Yeah, to validate I ran ONLY reporting server load and CPU did not throttle at 30% as per your script. Pinal: Oh! I get it here is the answer - CAP_CPU_PERCENT = 30. Use it. Jeff: What is that, I think your earlier script says it will throttle the Reporting Service workload and Application/OLTP workload and balance it. Pinal: Exactly, that is correct. Jeff: You need to write more in email buddy! Just like your blogs, your answers do not make sense! No Offense! Pinal: Hmm…feedback well taken. Let me try again. In SQL Server 2012 there are a few enhancements with regards to SQL Server Resource Governor. One of the enhancement is how the resources are allocated. Let me explain you with examples. Configuration: [Read Earlier Post] Reporting Workload: MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30 Application/OLTP Workload: MIN_CPU_PERCENT=50, MAX_CPU_PERCENT=100 Example 1: If there is only Reporting Workload on the server: SQL Server will not limit usage of CPU to only 30% workload but SQL Server instance will use all available CPU (if needed). In another word in this scenario it will use more than 30% CPU. Example 2: If there is Reproting Workload and heavy Application/OLTP workload: SQL Server will allocate a maximum of 30% CPU resources to Reporting Workload and allocate remaining resources to heavy application/OLTP workload. The reason for this enhancement is for better utilization of the resources. Let us think, if there is only single workload, which we have limited to max CPU usage to 30%. The other unused available CPU resources is now wasted. In this situation SQL Server allows the workload to use more than 30% resources leading to overall improved/optimized performance. However, in the case of multiple workload where lots of resources are needed the limits specified in MAX_CPU_PERCENT are acknowledged. Example 3: If there is a situation where the max CPU workload has to be enforced: This is a very interesting scenario, in the case when the max CPU workload has to be enforced irrespective of the workload and enhanced algorithm, the keyword CAP_CPU_PERCENT is essential. It specifies a hard cap on the CPU bandwidth that all requests in the resource pool will receive. It will never let CPU usage for reporting workload to go over 30% in our case. You can use the key word as follows: -- Creating Resource Pool for Report Server CREATE RESOURCE POOL ReportServerPool WITH ( MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30, CAP_CPU_PERCENT=40, MIN_MEMORY_PERCENT=0, MAX_MEMORY_PERCENT=30) GO Notice that there is MAX_CPU_PERCENT=30 and CAP_CPU_PERCENT=40, what it means is that when SQL Server Instance is under heavy load under different workload it will use the maximum CPU at 30%. However, when the SQL Server instance is not under workload it will go over the 30% limit. However, as CAP_CPU_PERCENT is set to 40, it will not go over 40% in any case by limiting the usage of CPU. CAP_CPU_PERCENT puts a hard limit on the resources usage by workload. Jeff: Nice Pinal, you should blog about it. [A day passes by] Pinal: Jeff, it is done! Click here to read it. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Service Broker

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  • SQL SERVER – Guest Post by Sandip Pani – SQL Server Statistics Name and Index Creation

    - by pinaldave
    Sometimes something very small or a common error which we observe in daily life teaches us new things. SQL Server Expert Sandip Pani (winner of Joes 2 Pros Contests) has come across similar experience. Sandip has written a guest post on an error he faced in his daily work. Sandip is working for QSI Healthcare as an Associate Technical Specialist and have more than 5 years of total experience. He blogs at SQLcommitted.com and contribute in various forums. His social media hands are LinkedIn, Facebook and Twitter. Once I faced following error when I was working on performance tuning project and attempt to create an Index. Mug 1913, Level 16, State 1, Line 1 The operation failed because an index or statistics with name ‘Ix_Table1_1′ already exists on table ‘Table1′. The immediate reaction to the error was that I might have created that index earlier and when I researched it further I found the same as the index was indeed created two times. This totally makes sense. This can happen due to many reasons for example if the user is careless and executes the same code two times as well, when he attempts to create index without checking if there was index already on the object. However when I paid attention to the details of the error, I realize that error message also talks about statistics along with the index. I got curious if the same would happen if I attempt to create indexes with the same name as statistics already created. There are a few other questions also prompted in my mind. I decided to do a small demonstration of the subject and build following demonstration script. The goal of my experiment is to find out the relation between statistics and the index. Statistics is one of the important input parameter for the optimizer during query optimization process. If the query is nontrivial then only optimizer uses statistics to perform a cost based optimization to select a plan. For accuracy and further learning I suggest to read MSDN. Now let’s find out the relationship between index and statistics. We will do the experiment in two parts. i) Creating Index ii) Creating Statistics We will be using the following T-SQL script for our example. IF (OBJECT_ID('Table1') IS NOT NULL) DROP TABLE Table1 GO CREATE TABLE Table1 (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO We will be using following two queries to check if there are any index or statistics on our sample table Table1. -- Details of Index SELECT OBJECT_NAME(OBJECT_ID) AS TableName, Name AS IndexName, type_desc FROM sys.indexes WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO -- Details of Statistics SELECT OBJECT_NAME(OBJECT_ID) TableName, Name AS StatisticsName FROM sys.stats WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO When I ran above two scripts on the table right after it was created it did not give us any result which was expected. Now let us begin our test. 1) Create an index on the table Create following index on the table. CREATE NONCLUSTERED INDEX Ix_Table1_1 ON Table1(Col1) GO Now let us use above two scripts and see their results. We can see that when we created index at the same time it created statistics also with the same name. Before continuing to next set of demo – drop the table using following script and re-create the table using a script provided at the beginning of the table. DROP TABLE table1 GO 2) Create a statistic on the table Create following statistics on the table. CREATE STATISTICS Ix_table1_1 ON Table1 (Col1) GO Now let us use above two scripts and see their results. We can see that when we created statistics Index is not created. The behavior of this experiment is different from the earlier experiment. Clean up the table setup using the following script: DROP TABLE table1 GO Above two experiments teach us very valuable lesson that when we create indexes, SQL Server generates the index and statistics (with the same name as the index name) together. Now due to the reason if we have already had statistics with the same name but not the index, it is quite possible that we will face the error to create the index even though there is no index with the same name. A Quick Check To validate that if we create statistics first and then index after that with the same name, it will throw an error let us run following script in SSMS. Make sure to drop the table and clean up our sample table at the end of the experiment. -- Create sample table CREATE TABLE TestTable (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO -- Create Statistics CREATE STATISTICS IX_TestTable_1 ON TestTable (Col1) GO -- Create Index CREATE NONCLUSTERED INDEX IX_TestTable_1 ON TestTable(Col1) GO -- Check error /*Msg 1913, Level 16, State 1, Line 2 The operation failed because an index or statistics with name 'IX_TestTable_1' already exists on table 'TestTable'. */ -- Clean up DROP TABLE TestTable GO While creating index it will throw the following error as statistics with the same name is already created. In simple words – when we create index the name of the index should be different from any of the existing indexes and statistics. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Statistics

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  • Using the Data Form Web Part (SharePoint 2010) Site Agnostically!

    - by David Jacobus
    Originally posted on: http://geekswithblogs.net/djacobus/archive/2013/10/24/154465.aspxAs a Developer whom has worked closely with web designers (Power users) in a SharePoint environment, I have come across the issue of making the Data Form Web Part reusable across the site collection! In SharePoint 2007 it was very easy and this blog pointed the way to make it happen: Josh Gaffey's Blog. In SharePoint 2010 something changed! This method failed except for using a Data Form Web Part that pointed to a list in the Site Collection Root! I am making this discussion relative to a developer whom creates a solution (WSP) with all the artifacts embedded and the user shouldn’t have any involvement in the process except to activate features. The Scenario: 1. A Power User creates a Data Form Web Part using SharePoint Designer 2010! It is a great web part the uses all the power of SharePoint Designer and XSLT (Conditional formatting, etc.). 2. Other Users in the site collection want to use that specific web part in sub sites in the site collection. Pointing to a list with the same name, not at the site collection root! The Issues: 1. The Data Form Web Part Data Source uses a List ID (GUID) to point to the specific list. Which means a list in a sub site will have a list with a new GUID different than the one which was created with SharePoint Designer! Obviously, the List needs to be the same List (Fields, Content Types, etc.) with different data. 2. How can we make this web part site agnostic, and dependent only on the lists Name? I had this problem come up over and over and decided to put my solution forward! The Solution: 1. Use the XSL of the Data Form Web Part Created By the Power User in SharePoint Designer! 2. Extend the OOTB Data Form Web Part to use this XSL and Point to a List by name. The solution points to a hybrid solution that requires some coding (Developer) and the XSL (Power User) artifacts put together in a Visual Studio SharePoint Solution. Here are the solution steps in summary: 1. Create an empty SharePoint project in Visual Studio 2. Create a Module and Feature and put the XSL file created by the Power User into it a. Scope the feature to web 3. Create a Feature Receiver to Create the List. The same list from which the Data Form Web Part was created with by the Power User. a. Scope the feature to web 4. Create a Web Part extending the Data Form Web a. Point the Data Form Web Part to point to the List by Name b. Point the Data Form Web Part XSL link to the XSL added using the Module feature c. Scope The feature to Site i. This is because all web parts are in the site collection web part gallery. So in a Narrative Summary: We are creating a list in code which has the same name and (site Columns) as the list from which the Power User created the Data Form Web Part Using SharePoint Designer. We are creating a Web Part in code which extends the OOTB Data Form Web Part to point to a list by name and use the XSL created by the Power User. Okay! Here are the steps with images and code! At the end of this post I will provide a link to the code for a solution which works in any site! I want to TOOT the HORN for the power of this solution! It is the mantra a use with all my clients! What is a basic skill a SharePoint Developer: Create an application that uses the data from a SharePoint list and make that data visible to the user in a manner which meets requirements! Create an Empty SharePoint 2010 Project Here I am naming my Project DJ.DataFormWebPart Create a Code Folder Copy and paste the Extension and Utilities classes (Found in the solution provided at the end of this post) Change the Namespace to match this project The List to which the Data Form Web Part which was used to make the XSL by the Power User in SharePoint Designer is now going to be created in code! If already in code, then all the better! Here I am going to create a list in the site collection root and add some data to it! For the purpose of this discussion I will actually create this list in code before using SharePoint Designer for simplicity! So here I create the List and deploy it within this solution before I do anything else. I will use a List I created before for demo purposes. Footer List is used within the footer of my master page. Add a new Feature: Here I name the Feature FooterList and add a Feature Event Receiver: Here is the code for the Event Receiver: I have a previous blog post about adding lists in code so I will not take time to narrate this code: using System; using System.Runtime.InteropServices; using System.Security.Permissions; using Microsoft.SharePoint; using DJ.DataFormWebPart.Code; namespace DJ.DataFormWebPart.Features.FooterList { /// <summary> /// This class handles events raised during feature activation, deactivation, installation, uninstallation, and upgrade. /// </summary> /// <remarks> /// The GUID attached to this class may be used during packaging and should not be modified. /// </remarks> [Guid("a58644fd-9209-41f4-aa16-67a53af7a9bf")] public class FooterListEventReceiver : SPFeatureReceiver { SPWeb currentWeb = null; SPSite currentSite = null; const string columnGroup = "DJ"; const string ctName = "FooterContentType"; // Uncomment the method below to handle the event raised after a feature has been activated. public override void FeatureActivated(SPFeatureReceiverProperties properties) { using (SPWeb spWeb = properties.GetWeb() as SPWeb) { using (SPSite site = new SPSite(spWeb.Site.ID)) { using (SPWeb rootWeb = site.OpenWeb(site.RootWeb.ID)) { //add the fields addFields(rootWeb); //add content type SPContentType testCT = rootWeb.ContentTypes[ctName]; // we will not create the content type if it exists if (testCT == null) { //the content type does not exist add it addContentType(rootWeb, ctName); } if ((spWeb.Lists.TryGetList("FooterList") == null)) { //create the list if it dosen't to exist CreateFooterList(spWeb, site); } } } } } #region ContentType public void addFields(SPWeb spWeb) { Utilities.addField(spWeb, "Link", SPFieldType.URL, false, columnGroup); Utilities.addField(spWeb, "Information", SPFieldType.Text, false, columnGroup); } private static void addContentType(SPWeb spWeb, string name) { SPContentType myContentType = new SPContentType(spWeb.ContentTypes["Item"], spWeb.ContentTypes, name) { Group = columnGroup }; spWeb.ContentTypes.Add(myContentType); addContentTypeLinkages(spWeb, myContentType); myContentType.Update(); } public static void addContentTypeLinkages(SPWeb spWeb, SPContentType ct) { Utilities.addContentTypeLink(spWeb, "Link", ct); Utilities.addContentTypeLink(spWeb, "Information", ct); } private void CreateFooterList(SPWeb web, SPSite site) { Guid newListGuid = web.Lists.Add("FooterList", "Footer List", SPListTemplateType.GenericList); SPList newList = web.Lists[newListGuid]; newList.ContentTypesEnabled = true; var footer = site.RootWeb.ContentTypes[ctName]; newList.ContentTypes.Add(footer); newList.ContentTypes.Delete(newList.ContentTypes["Item"].Id); newList.Update(); var view = newList.DefaultView; //add all view fields here //view.ViewFields.Add("NewsTitle"); view.ViewFields.Add("Link"); view.ViewFields.Add("Information"); view.Update(); } } } Basically created a content type with two site columns Link and Information. I had to change some code as we are working at the SPWeb level and need Content Types at the SPSite level! I’ll use a new Site Collection for this demo (Best Practice) keep old artifacts from impinging on development: Next we will add this list to the root of the site collection by deploying this solution, add some data and then use SharePoint Designer to create a Data Form Web Part. The list has been added, now let’s add some data: Okay let’s add a Data Form Web Part in SharePoint Designer. Create a new web part page in the site pages library: I will name it TestWP.aspx and edit it in advanced mode: Let’s add an empty Data Form Web Part to the web part zone: Click on the web part to add a data source: Choose FooterList in the Data Source menu: Choose appropriate fields and select insert as multiple item view: Here is what it look like after insertion: Let’s add some conditional formatting if the information filed is not blank: Choose Create (right side) apply formatting: Choose the Information Field and set the condition not null: Click Set Style: Here is the result: Okay! Not flashy but simple enough for this demo. Remember this is the job of the Power user! All we want from this web part is the XLS-Style Sheet out of SharePoint Designer. We are going to use it as the XSL for our web part which we will be creating next. Let’s add a web part to our project extending the OOTB Data Form Web Part. Add new item from the Visual Studio add menu: Choose Web Part: Change WebPart to DataFormWebPart (Oh well my namespace needs some improvement, but it will sure make it readily identifiable as an extended web part!) Below is the code for this web part: using System; using System.ComponentModel; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using Microsoft.SharePoint; using Microsoft.SharePoint.WebControls; using System.Text; namespace DJ.DataFormWebPart.DataFormWebPart { [ToolboxItemAttribute(false)] public class DataFormWebPart : Microsoft.SharePoint.WebPartPages.DataFormWebPart { protected override void OnInit(EventArgs e) { base.OnInit(e); this.ChromeType = PartChromeType.None; this.Title = "FooterListDF"; try { //SPSite site = SPContext.Current.Site; SPWeb web = SPContext.Current.Web; SPList list = web.Lists.TryGetList("FooterList"); if (list != null) { string queryList1 = "<Query><Where><IsNotNull><FieldRef Name='Title' /></IsNotNull></Where><OrderBy><FieldRef Name='Title' Ascending='True' /></OrderBy></Query>"; uint maximumRowList1 = 10; SPDataSource dataSourceList1 = GetDataSource(list.Title, web.Url, list, queryList1, maximumRowList1); this.DataSources.Add(dataSourceList1); this.XslLink = web.Url + "/Assests/Footer.xsl"; this.ParameterBindings = BuildDataFormParameters(); this.DataBind(); } } catch (Exception ex) { this.Controls.Add(new LiteralControl("ERROR: " + ex.Message)); } } private SPDataSource GetDataSource(string dataSourceId, string webUrl, SPList list, string query, uint maximumRow) { SPDataSource dataSource = new SPDataSource(); dataSource.UseInternalName = true; dataSource.ID = dataSourceId; dataSource.DataSourceMode = SPDataSourceMode.List; dataSource.List = list; dataSource.SelectCommand = "" + query + ""; Parameter listIdParam = new Parameter("ListID"); listIdParam.DefaultValue = list.ID.ToString( "B").ToUpper(); Parameter maximumRowsParam = new Parameter("MaximumRows"); maximumRowsParam.DefaultValue = maximumRow.ToString(); QueryStringParameter rootFolderParam = new QueryStringParameter("RootFolder", "RootFolder"); dataSource.SelectParameters.Add(listIdParam); dataSource.SelectParameters.Add(maximumRowsParam); dataSource.SelectParameters.Add(rootFolderParam); dataSource.UpdateParameters.Add(listIdParam); dataSource.DeleteParameters.Add(listIdParam); dataSource.InsertParameters.Add(listIdParam); return dataSource; } private string BuildDataFormParameters() { StringBuilder parameters = new StringBuilder("<ParameterBindings><ParameterBinding Name=\"dvt_apos\" Location=\"Postback;Connection\"/><ParameterBinding Name=\"UserID\" Location=\"CAMLVariable\" DefaultValue=\"CurrentUserName\"/><ParameterBinding Name=\"Today\" Location=\"CAMLVariable\" DefaultValue=\"CurrentDate\"/>"); parameters.Append("<ParameterBinding Name=\"dvt_firstrow\" Location=\"Postback;Connection\"/>"); parameters.Append("<ParameterBinding Name=\"dvt_nextpagedata\" Location=\"Postback;Connection\"/>"); parameters.Append("<ParameterBinding Name=\"dvt_adhocmode\" Location=\"Postback;Connection\"/>"); parameters.Append("<ParameterBinding Name=\"dvt_adhocfiltermode\" Location=\"Postback;Connection\"/>"); parameters.Append("</ParameterBindings>"); return parameters.ToString(); } } } The OnInit method we use to set the list name and the XSL Link property of the Data Form Web Part. We do not have the link to XSL in our Solution so we will add the XSL now: Add a Module in the Visual Studio add menu: Rename Sample.txt in the module to footer.xsl and then copy the XSL from SharePoint Designer Look at elements.xml to where the footer.xsl is being provisioned to which is Assets/footer.xsl, make sure the Web parts xsl link is pointing to this url: Okay we are good to go! Let’s check our features and package: DataFormWebPart should be scoped to site and have the web part: The Footer List feature should be scoped to web and have the Assets module (Okay, I see, a spelling issue but it won’t affect this demo) If everything is correct we should be able to click a couple of sub site feature activations and have our list and web part in a sub site. (In fact this solution can be activated anywhere) Here is the list created at SubSite1 with new data It. Next let’s add the web part on a test page and see if it works as expected: It does! So we now have a repeatable way to use a WSP to move a Data Form Web Part around our sites! Here is a link to the code: DataFormWebPart Solution

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  • Integrate Microsoft Translator into your ASP.Net application

    - by sreejukg
    In this article I am going to explain how easily you can integrate the Microsoft translator API to your ASP.Net application. Why we need a translation API? Once you published a website, you are opening a channel to the global audience. So making the web content available only in one language doesn’t cover all your audience. Especially when you are offering products/services it is important to provide contents in multiple languages. Users will be more comfortable when they see the content in their native language. How to achieve this, hiring translators and translate the content to all your user’s languages will cost you lot of money, and it is not a one time job, you need to translate the contents on the go. What is the alternative, we need to look for machine translation. Thankfully there are some translator engines available that gives you API level access, so that automatically you can translate the content and display to the user. Microsoft Translator API is an excellent set of web service APIs that allows developers to use the machine translation technology in their own applications. The Microsoft Translator API is offered through Windows Azure market place. In order to access the data services published in Windows Azure market place, you need to have an account. The registration process is simple, and it is common for all the services offered through the market place. Last year I had written an article about Bing Search API, where I covered the registration process. You can refer the article here. http://weblogs.asp.net/sreejukg/archive/2012/07/04/integrate-bing-search-api-to-asp-net-application.aspx Once you registered with Windows market place, you will get your APP ID. Now you can visit the Microsoft Translator page and click on the sign up button. http://datamarket.azure.com/dataset/bing/microsofttranslator As you can see, there are several options available for you to subscribe. There is a free version available, great. Click on the sign up button under the package that suits you. Clicking on the sign up button will bring the sign up form, where you need to agree on the terms and conditions and go ahead. You need to have a windows live account in order to sign up for any service available in Windows Azure market place. Once you signed up successfully, you will receive the thank you page. You can download the C# class library from here so that the integration can be made without writing much code. The C# file name is TranslatorContainer.cs. At any point of time, you can visit https://datamarket.azure.com/account/datasets to see the applications you are subscribed to. Click on the Use link next to each service will give you the details of the application. You need to not the primary account key and URL of the service to use in your application. Now let us start our ASP.Net project. I have created an empty ASP.Net web application using Visual Studio 2010 and named it Translator Sample, any name could work. By default, the web application in solution explorer looks as follows. Now right click the project and select Add -> Existing Item and then browse to the TranslatorContainer.cs. Now let us create a page where user enter some data and perform the translation. I have added a new web form to the project with name Translate.aspx. I have placed one textbox control for user to type the text to translate, the dropdown list to select the target language, a label to display the translated text and a button to perform the translation. For the dropdown list I have selected some languages supported by Microsoft translator. You can get all the supported languages with their codes from the below link. http://msdn.microsoft.com/en-us/library/hh456380.aspx The form looks as below in the design surface of Visual Studio. All the class libraries in the windows market place requires reference to System.Data.Services.Client, let us add the reference. You can find the documentation of how to use the downloaded class library from the below link. http://msdn.microsoft.com/en-us/library/gg312154.aspx Let us evaluate the translatorContainer.cs file. You can refer the code and it is self-explanatory. Note the namespace name used (Microsoft), you need to add the namespace reference to your page. I have added the following event for the translate button. The code is self-explanatory. You are creating an object of TranslatorContainer class by passing the translation service URL. Now you need to set credentials for your Translator container object, which will be your account key. The TranslatorContainer support a method that accept a text input, source language and destination language and returns DataServiceQuery<Translation>. Let us see this working, I just ran the application and entered Good Morning in the Textbox. Selected target language and see the output as follows. It is easy to build great translator applications using Microsoft translator API, and there is a reasonable amount of translation you can perform in your application for free. For enterprises, you can subscribe to the appropriate package and make your application multi-lingual.

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  • SQL SERVER – Fundamentals of Columnstore Index

    - by pinaldave
    There are two kind of storage in database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data is relevant or not, column store queries need only to search much lesser number of the columns. This means major increases in search speed and hard drive use. Additionally, the column store indexes are heavily compressed, which translates to even greater memory and faster searches. I am sure this looks very exciting and it does not mean that you convert every single index from row store to column store index. One has to understand the proper places where to use row store or column store indexes. Let us understand in this article what is the difference in Columnstore type of index. Column store indexes are run by Microsoft’s VertiPaq technology. However, all you really need to know is that this method of storing data is columns on a single page is much faster and more efficient. Creating a column store index is very easy, and you don’t have to learn new syntax to create them. You just need to specify the keyword “COLUMNSTORE” and enter the data as you normally would. Keep in mind that once you add a column store to a table, though, you cannot delete, insert or update the data – it is READ ONLY. However, since column store will be mainly used for data warehousing, this should not be a big problem. You can always use partitioning to avoid rebuilding the index. A columnstore index stores each column in a separate set of disk pages, rather than storing multiple rows per page as data traditionally has been stored. The difference between column store and row store approaches is illustrated below: In case of the row store indexes multiple pages will contain multiple rows of the columns spanning across multiple pages. In case of column store indexes multiple pages will contain multiple single columns. This will lead only the columns needed to solve a query will be fetched from disk. Additionally there is good chance that there will be redundant data in a single column which will further help to compress the data, this will have positive effect on buffer hit rate as most of the data will be in memory and due to same it will not need to be retrieved. Let us see small example of how columnstore index improves the performance of the query on a large table. As a first step let us create databaseset which is large enough to show performance impact of columnstore index. The time taken to create sample database may vary on different computer based on the resources. USE AdventureWorks GO -- Create New Table CREATE TABLE [dbo].[MySalesOrderDetail]( [SalesOrderID] [int] NOT NULL, [SalesOrderDetailID] [int] NOT NULL, [CarrierTrackingNumber] [nvarchar](25) NULL, [OrderQty] [smallint] NOT NULL, [ProductID] [int] NOT NULL, [SpecialOfferID] [int] NOT NULL, [UnitPrice] [money] NOT NULL, [UnitPriceDiscount] [money] NOT NULL, [LineTotal] [numeric](38, 6) NOT NULL, [rowguid] [uniqueidentifier] NOT NULL, [ModifiedDate] [datetime] NOT NULL ) ON [PRIMARY] GO -- Create clustered index CREATE CLUSTERED INDEX [CL_MySalesOrderDetail] ON [dbo].[MySalesOrderDetail] ( [SalesOrderDetailID]) GO -- Create Sample Data Table -- WARNING: This Query may run upto 2-10 minutes based on your systems resources INSERT INTO [dbo].[MySalesOrderDetail] SELECT S1.* FROM Sales.SalesOrderDetail S1 GO 100 Now let us do quick performance test. I have kept STATISTICS IO ON for measuring how much IO following queries take. In my test first I will run query which will use regular index. We will note the IO usage of the query. After that we will create columnstore index and will measure the IO of the same. -- Performance Test -- Comparing Regular Index with ColumnStore Index USE AdventureWorks GO SET STATISTICS IO ON GO -- Select Table with regular Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO -- Table 'MySalesOrderDetail'. Scan count 1, logical reads 342261, physical reads 0, read-ahead reads 0. -- Create ColumnStore Index CREATE NONCLUSTERED COLUMNSTORE INDEX [IX_MySalesOrderDetail_ColumnStore] ON [MySalesOrderDetail] (UnitPrice, OrderQty, ProductID) GO -- Select Table with Columnstore Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO It is very clear from the results that query is performance extremely fast after creating ColumnStore Index. The amount of the pages it has to read to run query is drastically reduced as the column which are needed in the query are stored in the same page and query does not have to go through every single page to read those columns. If we enable execution plan and compare we can see that column store index performance way better than regular index in this case. Let us clean up the database. -- Cleanup DROP INDEX [IX_MySalesOrderDetail_ColumnStore] ON [dbo].[MySalesOrderDetail] GO TRUNCATE TABLE dbo.MySalesOrderDetail GO DROP TABLE dbo.MySalesOrderDetail GO In future posts we will see cases where Columnstore index is not appropriate solution as well few other tricks and tips of the columnstore index. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Liskov Substitution Principle and the Oft Forgot Third Wheel

    - by Stacy Vicknair
    Liskov Substitution Principle (LSP) is a principle of object oriented programming that many might be familiar with from the SOLID principles mnemonic from Uncle Bob Martin. The principle highlights the relationship between a type and its subtypes, and, according to Wikipedia, is defined by Barbara Liskov and Jeanette Wing as the following principle:   Let be a property provable about objects of type . Then should be provable for objects of type where is a subtype of .   Rectangles gonna rectangulate The iconic example of this principle is illustrated with the relationship between a rectangle and a square. Let’s say we have a class named Rectangle that had a property to set width and a property to set its height. 1: Public Class Rectangle 2: Overridable Property Width As Integer 3: Overridable Property Height As Integer 4: End Class   We all at some point here that inheritance mocks an “IS A” relationship, and by gosh we all know square IS A rectangle. So let’s make a square class that inherits from rectangle. However, squares do maintain the same length on every side, so let’s override and add that behavior. 1: Public Class Square 2: Inherits Rectangle 3:  4: Private _sideLength As Integer 5:  6: Public Overrides Property Width As Integer 7: Get 8: Return _sideLength 9: End Get 10: Set(value As Integer) 11: _sideLength = value 12: End Set 13: End Property 14:  15: Public Overrides Property Height As Integer 16: Get 17: Return _sideLength 18: End Get 19: Set(value As Integer) 20: _sideLength = value 21: End Set 22: End Property 23: End Class   Now, say we had the following test: 1: Public Sub SetHeight_DoesNotAffectWidth(rectangle As Rectangle) 2: 'arrange 3: Dim expectedWidth = 4 4: rectangle.Width = 4 5:  6: 'act 7: rectangle.Height = 7 8:  9: 'assert 10: Assert.AreEqual(expectedWidth, rectangle.Width) 11: End Sub   If we pass in a rectangle, this test passes just fine. What if we pass in a square?   This is where we see the violation of Liskov’s Principle! A square might "IS A” to a rectangle, but we have differing expectations on how a rectangle should function than how a square should! Great expectations Here’s where we pat ourselves on the back and take a victory lap around the office and tell everyone about how we understand LSP like a boss. And all is good… until we start trying to apply it to our work. If I can’t even change functionality on a simple setter without breaking the expectations on a parent class, what can I do with subtyping? Did Liskov just tell me to never touch subtyping again? The short answer: NO, SHE DIDN’T. When I first learned LSP, and from those I’ve talked with as well, I overlooked a very important but not appropriately stressed quality of the principle: our expectations. Our inclination is to want a logical catch-all, where we can easily apply this principle and wipe our hands, drop the mic and exit stage left. That’s not the case because in every different programming scenario, our expectations of the parent class or type will be different. We have to set reasonable expectations on the behaviors that we expect out of the parent, then make sure that those expectations are met by the child. Any expectations not explicitly expected of the parent aren’t expected of the child either, and don’t register as a violation of LSP that prevents implementation. You can see the flexibility mentioned in the Wikipedia article itself: A typical example that violates LSP is a Square class that derives from a Rectangle class, assuming getter and setter methods exist for both width and height. The Square class always assumes that the width is equal with the height. If a Square object is used in a context where a Rectangle is expected, unexpected behavior may occur because the dimensions of a Square cannot (or rather should not) be modified independently. This problem cannot be easily fixed: if we can modify the setter methods in the Square class so that they preserve the Square invariant (i.e., keep the dimensions equal), then these methods will weaken (violate) the postconditions for the Rectangle setters, which state that dimensions can be modified independently. Violations of LSP, like this one, may or may not be a problem in practice, depending on the postconditions or invariants that are actually expected by the code that uses classes violating LSP. Mutability is a key issue here. If Square and Rectangle had only getter methods (i.e., they were immutable objects), then no violation of LSP could occur. What this means is that the above situation with a rectangle and a square can be acceptable if we do not have the expectation for width to leave height unaffected, or vice-versa, in our application. Conclusion – the oft forgot third wheel Liskov Substitution Principle is meant to act as a guidance and warn us against unexpected behaviors. Objects can be stateful and as a result we can end up with unexpected situations if we don’t code carefully. Specifically when subclassing, make sure that the subclass meets the expectations held to its parent. Don’t let LSP think you cannot deviate from the behaviors of the parent, but understand that LSP is meant to highlight the importance of not only the parent and the child class, but also of the expectations WE set for the parent class and the necessity of meeting those expectations in order to help prevent sticky situations.   Code examples, in both VB and C# Technorati Tags: LSV,Liskov Substitution Principle,Uncle Bob,Robert Martin,Barbara Liskov,Liskov

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  • Towards an F# .NET Reflector add-in

    - by CliveT
    When I had the opportunity to spent some time during Red Gate's recent "down tools" week on a project of my choice, the obvious project was an F# add-in for Reflector . To be honest, this was a bit of a misnomer as the amount of time in the designated week for coding was really less than three days, so it was always unlikely that very much progress would be made in such a small amount of time (and that certainly proved to be the case), but I did learn some things from the experiment. Like lots of problems, one useful technique is to take examples, get them to work, and then generalise to get something that works across the board. Unfortunately, I didn't have enough time to do the last stage. The obvious first step is to take a few function definitions, starting with the obvious hello world, moving on to a non-recursive function and finishing with the ubiquitous recursive Fibonacci function. let rec printMessage message  =     printfn  message let foo x  =    (x + 1) let rec fib x  =     if (x >= 2) then (fib (x - 1) + fib (x - 2)) else 1 The major problem in decompiling these simple functions is that Reflector has an in-memory object model that is designed to support object-oriented languages. In particular it has a return statement that allows function bodies to finish early. I used some of the in-built functionality to take the IL and produce an in-memory object model for the language, but then needed to write a transformer to push the return statements to the top of the tree to make it easy to render the code into a functional language. This tree transform works in some scenarios, but not in others where we simply regenerate code that looks more like CPS style. The next thing to get working was library level bindings of values where these values are calculated at runtime. let x = [1 ; 2 ; 3 ; 4] let y = List.map  (fun x -> foo x) x The way that this is translated into a set of classes for the underlying platform means that the code needs to follow references around, from the property exposing the calculated value to the class in which the code for generating the value is embedded. One of the strongest selling points of functional languages is the algebraic datatypes, which allow definitions via standard mathematical-style inductive definitions across the union cases. type Foo =     | Something of int     | Nothing type 'a Foo2 =     | Something2 of 'a     | Nothing2 Such a definition is compiled into a number of classes for the cases of the union, which all inherit from a class representing the type itself. It wasn't too hard to get such a de-compilation happening in the cases I tried. What did I learn from this? Firstly, that there are various bits of functionality inside Reflector that it would be useful for us to allow add-in writers to access. In particular, there are various implementations of the Visitor pattern which implement algorithms such as calculating the number of references for particular variables, and which perform various substitutions which could be more generally useful to add-in writers. I hope to do something about this at some point in the future. Secondly, when you transform a functional language into something that runs on top of an object-based platform, you lose some fidelity in the representation. The F# compiler leaves attributes in place so that tools can tell which classes represent classes from the source program and which are there for purposes of the implementation, allowing the decompiler to regenerate these constructs again. However, decompilation technology is a long way from being able to take unannotated IL and transform it into a program in a different language. For a simple function definition, like Fibonacci, I could write a simple static function and have it come out in F# as the same function, but it would be practically impossible to take a mass of class definitions and have a decompiler translate it automatically into an F# algebraic data type. What have we got out of this? Some data on the feasibility of implementing an F# decompiler inside Reflector, though it's hard at the moment to say how long this would take to do. The work we did is included the 6.5 EAP for Reflector that you can get from the EAP forum. All things considered though, it was a useful way to gain more familiarity with the process of writing an add-in and understand difficulties other add-in authors might experience. If you'd like to check out a video of Down Tools Week, click here.

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  • ResponseStatusLine protocol violation

    - by Tom Hines
    I parse/scrape a few web page every now and then and recently ran across an error that stated: "The server committed a protocol violation. Section=ResponseStatusLine".   After a few web searches, I found a couple of suggestions – one of which said the problem could be fixed by changing the HttpWebRequest ProtocolVersion to 1.0 with the command: 1: HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(strURI); 2: req.ProtocolVersion = HttpVersion.Version10;   …but that did not work in my particular case.   What DID work was the next suggestion I found that suggested the use of the setting: “useUnsafeHeaderParsing” either in the app.config file or programmatically. If added to the app.config, it would be: 1: <!-- after the applicationSettings --> 2: <system.net> 3: <settings> 4: <httpWebRequest useUnsafeHeaderParsing ="true"/> 5: </settings> 6: </system.net>   If done programmatically, it would look like this: C++: 1: // UUHP_CPP.h 2: #pragma once 3: using namespace System; 4: using namespace System::Reflection; 5:   6: namespace UUHP_CPP 7: { 8: public ref class CUUHP_CPP 9: { 10: public: 11: static bool UseUnsafeHeaderParsing(String^% strError) 12: { 13: Assembly^ assembly = Assembly::GetAssembly(System::Net::Configuration::SettingsSection::typeid); //__typeof 14: if (nullptr==assembly) 15: { 16: strError = "Could not access Assembly"; 17: return false; 18: } 19:   20: Type^ type = assembly->GetType("System.Net.Configuration.SettingsSectionInternal"); 21: if (nullptr==type) 22: { 23: strError = "Could not access internal settings"; 24: return false; 25: } 26:   27: Object^ obj = type->InvokeMember("Section", 28: BindingFlags::Static | BindingFlags::GetProperty | BindingFlags::NonPublic, 29: nullptr, nullptr, gcnew array<Object^,1>(0)); 30:   31: if(nullptr == obj) 32: { 33: strError = "Could not invoke Section member"; 34: return false; 35: } 36:   37: FieldInfo^ fi = type->GetField("useUnsafeHeaderParsing", BindingFlags::NonPublic | BindingFlags::Instance); 38: if(nullptr == fi) 39: { 40: strError = "Could not access useUnsafeHeaderParsing field"; 41: return false; 42: } 43:   44: if (!(bool)fi->GetValue(obj)) 45: { 46: fi->SetValue(obj, true); 47: } 48:   49: return true; 50: } 51: }; 52: } C# (CSharp): 1: using System; 2: using System.Reflection; 3:   4: namespace UUHP_CS 5: { 6: public class CUUHP_CS 7: { 8: public static bool UseUnsafeHeaderParsing(ref string strError) 9: { 10: Assembly assembly = Assembly.GetAssembly(typeof(System.Net.Configuration.SettingsSection)); 11: if (null == assembly) 12: { 13: strError = "Could not access Assembly"; 14: return false; 15: } 16:   17: Type type = assembly.GetType("System.Net.Configuration.SettingsSectionInternal"); 18: if (null == type) 19: { 20: strError = "Could not access internal settings"; 21: return false; 22: } 23:   24: object obj = type.InvokeMember("Section", 25: BindingFlags.Static | BindingFlags.GetProperty | BindingFlags.NonPublic, 26: null, null, new object[] { }); 27:   28: if (null == obj) 29: { 30: strError = "Could not invoke Section member"; 31: return false; 32: } 33:   34: // If it's not already set, set it. 35: FieldInfo fi = type.GetField("useUnsafeHeaderParsing", BindingFlags.NonPublic | BindingFlags.Instance); 36: if (null == fi) 37: { 38: strError = "Could not access useUnsafeHeaderParsing field"; 39: return false; 40: } 41:   42: if (!Convert.ToBoolean(fi.GetValue(obj))) 43: { 44: fi.SetValue(obj, true); 45: } 46:   47: return true; 48: } 49: } 50: }   F# (FSharp): 1: namespace UUHP_FS 2: open System 3: open System.Reflection 4: module CUUHP_FS = 5: let UseUnsafeHeaderParsing(strError : byref<string>) : bool = 6: // 7: let assembly : Assembly = Assembly.GetAssembly(typeof<System.Net.Configuration.SettingsSection>) 8: if (null = assembly) then 9: strError <- "Could not access Assembly" 10: false 11: else 12: 13: let myType : Type = assembly.GetType("System.Net.Configuration.SettingsSectionInternal") 14: if (null = myType) then 15: strError <- "Could not access internal settings" 16: false 17: else 18: 19: let obj : Object = myType.InvokeMember("Section", BindingFlags.Static ||| BindingFlags.GetProperty ||| BindingFlags.NonPublic, null, null, Array.zeroCreate 0) 20: if (null = obj) then 21: strError <- "Could not invoke Section member" 22: false 23: else 24: 25: // If it's not already set, set it. 26: let fi : FieldInfo = myType.GetField("useUnsafeHeaderParsing", BindingFlags.NonPublic ||| BindingFlags.Instance) 27: if(null = fi) then 28: strError <- "Could not access useUnsafeHeaderParsing field" 29: false 30: else 31: 32: if (not(Convert.ToBoolean(fi.GetValue(obj)))) then 33: fi.SetValue(obj, true) 34: 35: // Now return true 36: true VB (Visual Basic): 1: Option Explicit On 2: Option Strict On 3: Imports System 4: Imports System.Reflection 5:   6: Public Class CUUHP_VB 7: Public Shared Function UseUnsafeHeaderParsing(ByRef strError As String) As Boolean 8:   9: Dim assembly As [Assembly] 10: assembly = [assembly].GetAssembly(GetType(System.Net.Configuration.SettingsSection)) 11:   12: If (assembly Is Nothing) Then 13: strError = "Could not access Assembly" 14: Return False 15: End If 16:   17: Dim type As Type 18: type = [assembly].GetType("System.Net.Configuration.SettingsSectionInternal") 19: If (type Is Nothing) Then 20: strError = "Could not access internal settings" 21: Return False 22: End If 23:   24: Dim obj As Object 25: obj = [type].InvokeMember("Section", _ 26: BindingFlags.Static Or BindingFlags.GetProperty Or BindingFlags.NonPublic, _ 27: Nothing, Nothing, New [Object]() {}) 28:   29: If (obj Is Nothing) Then 30: strError = "Could not invoke Section member" 31: Return False 32: End If 33:   34: ' If it's not already set, set it. 35: Dim fi As FieldInfo 36: fi = [type].GetField("useUnsafeHeaderParsing", BindingFlags.NonPublic Or BindingFlags.Instance) 37: If (fi Is Nothing) Then 38: strError = "Could not access useUnsafeHeaderParsing field" 39: Return False 40: End If 41:   42: If (Not Convert.ToBoolean(fi.GetValue(obj))) Then 43: fi.SetValue(obj, True) 44: End If 45:   46: Return True 47: End Function 48: End Class   Technorati Tags: C++,CPP,VB,Visual Basic,F#,FSharp,C#,CSharp,ResponseStatusLine,protocol violation

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  • Productivity vs Security [closed]

    - by nerijus
    Really do not know is this right place to ask such a questions. But it is about programming in a different light. So, currently contracting with company witch pretends to be big corporation. Everyone is so important that all small issues like developers are ignored. Give you a sample: company VPN is configured so that if you have VPN then HTTP traffic is banned. Bearing this in mind can you imagine my workflow: Morning. Ok time to get latest source. Ups, no VPN. Let’s connect. Click-click. 3 sec. wait time. Ok getting source. Do I have emails? Ups. VPN is on, can’t check my emails. Need to wait for source to come up. Finally here it is! Ok Click-click VPN is gone. What is in my email. Someone reported a bug. Good, let’s track it down. It is in TFS already. Oh, dam, I need VPN. Click-click. Ok, there is description. Yea, I have seen this issue in stachoverflow.com. Let’s go there. Ups, no internet. Click-click. No internet. What? IPconfig… DHCP server kicked me out. Dam. Renew ip. 1..2..3. Ok internet is back. Google: site: stachoverflow.com 3 min. I have solution. Great I love stackoverflow.com. Don’t want to remember days where there was no stackoveflow.com. Ok. Copy paste this like to studio. Dam, studio is stalled, can’t reach files on TFS. Click-click. VPN is back. Get source out, paste my code. Grand. Let’s see what other comments about an issue in stackoverflow.com tells. Hmm.. There is a link. Click. Dammit! No internet. Click-click. No internet. DHCP kicked me out. Dammit. Now it is even worse: this happens 3-4 times a day. After certain amount of VPN connections open\closed my internet goes down solid. Only way to get internet back is reboot. All my browser tabs/SQL windows/studio will be gone. This happened just now when I am typing this. Back to issue I am solving right now: I am getting frustrated - I do not care about better solution for this issue. Let’s do it somehow and forget. This Click-click barrier between internet and TFS kills me… Sounds familiar? You could say there are VPN settings to change. No! This is company laptop, not allowed to do changes. I am very very lucky to have admin privileges on my machine. Most of developers don’t. So just learned to live with this frustration. It takes away 40-60 minutes daily. Tried to email company support, admins. They are too important ant too busy with something that just ignored my little man’s problem. Politely ignored. Question is: Is this normal in corporate world? (Have been in States, Canada, Germany. Never seen this.)

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