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  • Logging on to two sites simultaneously

    - by James Wakefield
    I want to log on to two sites simultaneously to enable a single sign on solution. We have a smallish wiki that is created with Apple wiki and we have an intranet site on a aspx cms system by Elcom. Both use Active Directory for credentials. Currently they are on different domains, but we could enable a rewrite using our load-balancer (Citrix Netscaler) or IIS. These sites are on different servers, one a mysterious Mac system and the other an IIS v6.0 on windows 2003. Now I am almost certain that a reverse proxy set up will solve this but I really just need someone to agree that this solves this issue, and if there are things I should look out for what they might be. I just want to have an invisible log on screen in an iframe and enter clone the user name and password using javascript.

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  • PHP, since upgrading to 5.2.17 getting some warning ?

    - by Jules
    I can't reproduce this on my test server no idea why this is happening, other queries / functions work.. I'm getting this warning PHP Warning: mysql_connect() [<a href='function.mysql-connect'> function.mysql-connect</a>]: Can't connect to MySQL server on '--my isps server--' (10060) in D:\domains\mydomain.com\wwwroot\p hp\_stdfuncs.php on line 191 This function and others like it are having problems (but some are ok), this is my include file... function AddPageError($PageHandle, $Requested) { global $server; global $db; global $user; global $pass; global $sDebug; $con = mysql_connect($server,$user,$pass); I have an include file which sets those variables, as I say they work on other pages and functions.. No idea why ??

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  • initialize jquery slider with hidden input value from database.

    - by ludwigs3rd
    I'm using a slider as user input for a screen. Basically it's a bulk update screen where there is a table with multiple rows, thus multiple sliders. I created it so that the hidden value is what gets posted in the form. <td> <input class="percentageProvidedHidden" type="hidden" name='<%= "Values[" + i + "].Percentage" %>' value='<%=item.Percentage %>' /> <div class="percentageProvidedSlider"></div> </td> I have the update working just fine (move slider changes hidden input value, submit, values are updated in db), however, I can't get the damn thing to initialize with the value of the hidden input (note the "value: " parameter below). In this case I think $(this) isn't actually $('percentageProvidedSlider') but the page itself. Can someone help me get the slider value to initialize with the hidden input field? I'm using ASP .Net MVC 2 so if there are any methods I should try with that I welcome them as well. $('.percentageProvidedSlider').slider( { min: 0, max: 100, step: 25, value: $(this).parents('tr').find('input.percentageProvidedHidden').val(), slide: function(e, ui) { var mypos = ui.value; $(this).find('.ui-slider-handle').text(ui.value); }, change: function(event, ui) { var myVal = $(this).slider("option", "value"); $(this).parents('tr').find('input.percentageProvidedHidden').val(myVal); var myDropDown = $(this).parents('tr').find('select.verified'); } });

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  • Error "initializer element is not constant" when trying to initialize variable with const

    - by tomlogic
    I get an error on line 6 (initialize my_foo to foo_init) of the following program and I'm not sure I understand why. typedef struct foo_t { int a, b, c; } foo_t; const foo_t foo_init = { 1, 2, 3 }; foo_t my_foo = foo_init; int main() { return 0; } Keep in mind this is a simplified version of a larger, multi-file project I'm working on. The goal was to have a single constant in the object file, that multiple files could use to initialize a state structure. Since it's an embedded target with limited resources and the struct isn't that small, I don't want multiple copies of the source. I'd prefer not to use: #define foo_init { 1, 2, 3 } I'm also trying to write portable code, so I need a solution that's valid C89 or C99. Does this have to do with the ORGs in an object file? That initialized variables go into one ORG and are initialized by copying the contents of a second ORG? Maybe I'll just need to change my tactic, and have an initializing function do all of the copies at startup. Unless there are other ideas out there?

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  • Simple Sinatra Ajax Not Working

    - by proteantech
    I was trying make an AJAX call from a static file on my computer to a simple sinatra service. The ajax call was returning with an error and no details. The server logged no errors either. Another strange symptom was that the Origin in the request header was null. I turns out that you can't make cross domain ajax calls without a little extra effort. You can set the Access-Control-Allow-Origin header on your sinatra response to expose your service to external domains using a snippet like this: get '/hi' do response['Access-Control-Allow-Origin'] = '*' content_type 'text/plain' "Hello World" end There's also another header you can set to allow other HTTP Methods besides gets, Access-Control-Request-Method. You can find more information by searching around for CORS: Cross Origin Resource Sharing and the previously mentioned headers. Oh, and in case you want to do this in Rails as well you can do something like this in your controller: after_filter :set_access_control_headers def set_access_control_headers headers['Access-Control-Allow-Origin'] = '*' headers['Access-Control-Request-Method'] = '*' end

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  • How to get values from SQL query made by php?

    - by Ole Jak
    So I made a query like this global $connection; $query = "SELECT * FROM streams "; $streams_set = mysql_query($query, $connection); confirm_query($streams_set); in my DB there are filds ID, UID, SID, TIME (all INT type exept time) So I am triing to print query relult into form <form> <select class="multiselect" multiple="multiple" name="SIDs"> <?php global $connection; $query = "SELECT * FROM streams "; $streams_set = mysql_query($query, $connection); confirm_query($streams_set); $streams_count = mysql_num_rows($streams_set); for ($count=1; $count <= $streams_count; $count++) { echo "<option value=\"{$count}\""; echo ">{$count}</option>"; } ?> </select> <br/> <input type="submit" value="Submit Form"/> </form> How to print out as "option" "values" SID's from my sql query?

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  • How to initialize list with parent child relation

    - by user2917702
    Let's say I have the following classes. public class Parent { public string name; IList<Children> children; } public class Child { public string parentName; public int age; } As it is understandable, each parent can have multiple children, and we can have multiple parents. What is the best way to initialize these classes? Is it better to get all of the parents, and all of the children from database then use LINQ? IList<Parent> parents = GetParents()//assume this gets parents from db IList<Child> children = GetChildren() //assume this gets children from db foreach(Parent parent in parents) { parent.children = children.Where(x=>x.parentName==parent.name).ToList(); } or get all of the parents and iterate through each parent to query database by parentName to get children information? Due to requirement that I have, I cannot use datatable or dataset; I can only use datareader. IList<Parent> parents = GetParents()//assume this gets parents from db foreach(Parent parent in parents) { parent.children = GetChildrenByParentName();//assume this gets parents from db by parentName } Thank you

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  • Displaying Query Results Horizontally

    - by AndyD273
    I am wondering if it is possible to take the results of a query and return them as a CSV string instead of as a column of cells. Basically, we have a table called Customers, and we have a table called CustomerTypeLines, and each Customer can have multiple CustomerTypeLines. When I run a query against it, I run into problems when I want to check multiple types, for instance: Select * from Customers a Inner Join CustomerTypeLines b on a.CustomerID = b.CustomerID where b.CustomerTypeID = 14 and b.CustomerTypeID = 66 ...returns nothing because a customer can't have both on the same line, obviously. In order to make it work, I had to add a field to Customers called CustomerTypes that looks like ,14,66,67, so I can do a Where a.CustomerTypes like '%,14,%' and a.CustomerTypes like '%,66,%' which returns 85 rows. Of course this is a pain because I have to make my program rebuild this field for that Customer each time the CustomerTypeLines table is changed. It would be nice if I could do a sub query in my where that would do the work for me, so instead of returning the results like: 14 66 67 it would return them like ,14,66,67, Is this possible?

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  • What db fits me?

    - by afvasd
    Dear Everyone I am currently using mysql. I am finding that my schema is getting incredibly complicated. I seek to find a new db that will suit my needs: Let's assume I am building a news aggregrator (which collects news from multiple website). I then run algorithms to determine if two news from different sites are actually referring to the same topic. I run this algorithm to cluster news together. The relationship is depicted below: cluster \--news1 \--word1 \--word2 \--news2 \--word3 \--news3 \--word1 \--word3 And then I will apply some magic and determine the importance of each word. Summing all the importance of each word gives me the importance of a news article. Summing the importance of each news article gives me the importance of a cluster. Note that above cluster there are also subgroups( like split by region etc), and categories (like sports, etc) which I have to determine the importance of that in a particular day per se. I have used views in the past to do so, but I realized that views are very slow. So i will normally do an insert into an actual table and index them for better performance. As you can see this leads to multiple tables derived like (cluster, importance), (news, importance), (words, importance) etc which can get pretty messy. Also the "importance" metric will change. It has become increasingly difficult to alter tables, update data (which I am using TRUNCATE TABLE) and then inserting from null. I am currently looking into something schemaless like Mongodb. I do not need distributedness. I would very much want something that is reasonably fast (which can be indexed) and something that is a lot more flexible that traditional RDMBS. Also, I need something that has some kind of ORM because I personally like ORM a lot. I am currently using sqlalchemy Please help!

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  • What 20 Lines (or less) of code did you find really useful?

    - by Ygam
    You can share your code or other's code. Here's a snippet from an array function in Kohana: public static function rotate($source_array, $keep_keys = TRUE) { $new_array = array(); foreach ($source_array as $key => $value) { $value = ($keep_keys === TRUE) ? $value : array_values($value); foreach ($value as $k => $v) { $new_array[$k][$key] = $v; } } return $new_array; } It was helpful when I was uploading multiple images using multiple file upload forms. It turned this array array('images' => array( 'name' => array( 0 => 'img1', 1 => 'img0', 2 =>'img2' ), 'error' => array( 0 => '', 1 => '', 2 => '' into : array('images' => array( 0 => array( 'name' => 'img1' 'error' => '' ),//rest goes here How about you? What 20 or less lines of code did you find useful?

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  • Perl - Choose interface to connect through

    - by Dieterve
    I have 2 interfaces on my server, eth0 and eth0:0. Those are 2 different external ips and obviously 2 different reverse domains. When i open a IO::Socket::INET Perl uses the eth0 interface by default. I would like to use the second interface (eth0:0) because this has a different ip and i dont want to use my main ip/domain. I have absolutely no idea how to select which interface to connect through. Code i use to open a socket: my $sock = new IO::Socket::INET(PeerAddr => $server, PeerPort => $serverPort, Proto => 'tcp') or die "Can't connect to server: $!";

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  • How to approach socket programming between C# -> Java (Android)

    - by Alex
    I've recently knocked up a server/client app for Windows & Android that allows one to send a file from Windows to an android phone over a socket connection. It works great for a single file but trying to send multiple files over in a single stream is causing me problems. I've also realised that aside from the binary data, I will need to send messages over the socket to indicate error states and other application messages. I have little experience with network programming and and wondering what is the best way forward. Basically the C# server side of the app just goes into a listening state and uses Socket.SendFile to transmit the file. On Android I use the standard Java Socket.getInputStream() to receive the file. That works great for a single file transfer, but how should I handle multiple files and error/messaging information? Do I need to use a different socket for each file? Should I be using a higher level framework to handle this or can I send everything over the single socket? Any other suggestions for frameworks or learning materials?

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  • Page specific CSS or a single css file when developing a mobile (webkit) based site?

    - by Mike
    I am working on a mobile site for webkit browsers. I have been trying to find information on using multiple style sheets versus a single css file. There is a lot of information on this topic, but it not a lot of information pertaining to mobile browsers. My site will have a bunch of pages that while have page specific css. For a non-mobile site, it seems like generally people say that a single file will be faster, but that multiple files are easier to develop. However, on a mobile site is that still the case? If you put everything in one file, that will get cached after load, but that will make the first load slower. If you had page specific files, the first page would get loaded quicker, but every other page would then take a hit while making the page specific css http request. Does anyone have any thoughts on this? It sounds like they are saying one file is better as long as its under 1 MB (which my files def will)? http://www.yuiblog.com/blog/2010/07/12/mobile-browser-cache-limits-revisited/

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  • How to use strtok in C properly so there is no memory leak?

    - by user246392
    I am somewhat confused by what happens when you call strtok on a char pointer in C. I know that it modifies the contents of the string, so if I call strtok on a variable named 'line', its content will change. Assume I follow the bellow approach: void function myFunc(char* line) { // get a pointer to the original memory block char* garbageLine = line; // Do some work // Call strtok on 'line' multiple times until it returns NULL // Do more work free(garbageLine); } Further assume that 'line' is malloced before it is passed to myFunc. Am I supposed to free the original string after using strtok or does it do the job for us? Also, what happens if 'line' is not malloced and I attempt to use the function above? Is it safer to do the following instead? (Assume the programmer won't call free if he knows the line is not malloced) Invocation char* garbageLine = line; myFunc(line); free(garbageLine); Function definition void function myFunc(char* line) { // Do some work // Call strtok on 'line' multiple times until it returns NULL // Do more work }

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  • Initializing ExportFactory using MEF

    - by Riz
    Scenario Application has multiple parts. Each part is in separate dll and implements interface IFoo All such dlls are present in same directory (plugins) The application can instantiate multiple instances of each part Below is the code snippet for the interfaces, part(export) and the import. The problem I am running into is, the "factories" object is initialized with empty list. However, if I try container.Resolve(typeof(IEnumerable< IFoo )) I do get object with the part. But that doesn't serve my purpose (point 4). Can anyone point what I am doing wrong here? public interface IFoo { string Name { get; } } public interface IFooMeta { string CompType { get; } } Implementation of IFoo in separate Dll [ExportMetadata("CompType", "Foo1")] [Export(typeof(IFoo), RequiredCreationPolicy = CreationPolicy.NonShared))] public class Foo1 : IFoo { public string Name { get { return this.GetType().ToString(); } } } Main application that loads all the parts and instantiate them as needed class PartsManager { [ImportMany] private IEnumerable<ExportFactory<IFoo, IFooMeta>> factories; public PartsManager() { IContainer container = ConstructContainer(); factories = (IEnumerable<ExportFactory<IFoo, IFooMeta>>) container.Resolve(typeof(IEnumerable<ExportFactory<IFoo, IFooMeta>>)); } private static IContainer ConstructContainer() { var catalog = new DirectoryCatalog(@"C:\plugins\"); var builder = new ContainerBuilder(); builder.RegisterComposablePartCatalog(catalog); return builder.Build(); } public IFoo GetPart(string compType) { var matchingFactory = factories.FirstOrDefault( x => x.Metadata.CompType == compType); if (factories == null) { return null; } else { IFoo foo = matchingFactory.CreateExport().Value; return foo; } } }

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  • Online image resizer

    - by Happy
    Searching for some script or service for online image resizing. I should have the ability to throw my imagelink, like http://site.com/bigimage.jpg, and it must give me this image after resizing like http://site-were-image-resized.com/sdf4234f21f.png. It would be amazing, if I can give some values, like height and width. If I upload script on my own site, it should have the ability to resize external images from some domains. Tryed to use http://www.darrenhoyt.com/demo/timthumb/, but it doesn't work with external images.

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  • How can I get the file extensions from relative links in HTML text using Perl?

    - by Structure
    For example, scanning the contents of an HTML page with a Perl regular expression, I want to match all file extensions but not TLD's in domain names. To do this I am making the assumption that all file extensions must be within double quotes. I came up with the following, and it is working, however, I am failing to figure out a way to exclude the TLDs in the domains. This will return "com", "net", etc. m/"[^<>]+\.([0-9A-Za-z]*)"/g Is it possible to negate the match if there is more than one period between the quotes that are separated by text? (ie: match foo.bar.com but not ./ or ../) Edit I am using $1 to return the value within parentheses.

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  • Mercurial on shared network drive?

    - by user1164199
    Right now I have my repo on my local drive. In order to back it up, I have to copy .hg to a window's network drive. At Is it a good idea to put Mercurial Repository in shared Network drive?, Lasse Karlsen said the repo shouldn't be on a shared folder on a network server because "mercurial cannot reliably hold locks in all situations". Would this still be an issue when the repository is only updated by a single user? If so, can someone explain to me why the corruption happens? A while back our IT had problem setting up a mercurial server. I am very fond of mercurial (it has a great interface and is very easy to work with), but if it's going to be such a pain in the neck to set up for multiple users, I am willing to look for something else. Does anyone have any suggestions (with reasons)? I am looking for a revision control program that has the following attributes: 2. Good interface (allow you to easily see revision and changes to the code over multiple revisions). 3. Work as a local repo or a network repo. 4. IT will feel comfortable installing on their network. Thanks, Stephen

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  • Add Your Gmail Account to Outlook 2010 Using IMAP

    - by Mysticgeek
    If you’re upgrading from Outlook 2003 to 2010, you might want to use IMAP with your Gmail account to synchronize mail across multiple machines. Using our guide, you will be able to start using it in no time. Enable IMAP in Gmail First log into your Gmail account and open the Settings panel. Click on the Forwarding and POP/IMAP tab and verify IMAP is enabled and save changes. Next open Outlook 2010, click on the File tab to access the Backstage view. Click on Account Settings and Add and remove accounts or change existing connection settings. In the Account Settings window click on the New button. Enter in your name, email address, and password twice then click Next. Outlook will configure the email server settings, the amount of time it takes will vary. Provided everything goes correctly, the configuration will be successful and you can begin using your account. Manually Configure IMAP Settings If the above instructions don’t work, then we’ll need to manually configure the settings. Again, go into Auto Account Setup and select Manually configure server settings or additional server types and click Next.   Select Internet E-mail – Connect to POP or IMAP server to send and receive e-mail messages. Now we need to manually enter in our settings similar to the following. Under the Server Information section verify the following. Account Type: IMAP Incoming mail server: imap.gmail.com Outgoing mail server (SMTP): smtp.gmail.com Note: If you have a Google Apps account make sure to put the full email address ([email protected]) in the Your Name and User Name fields. Note: If you live outside of the US you might need to use imap.googlemail.com and smtp.googlemail.com Next, we need to click on the More Settings button… In the Internet E-mail Settings screen that pops up, click on the Outgoing Server tab, and check the box next to My outgoing server (SMTP) requires authentication. Also select the radio button next to Use same settings as my incoming mail server. In the same window click on the Advanced tab and verify the following. Incoming server: 993 Incoming server encrypted connection: SSL Outgoing server encrypted connection TLS Outgoing server: 587 Note: You will need to change the Outgoing server encrypted connection first, otherwise it will default back to port 25. Also, if TLS doesn’t work, we were able to successfully use Auto. Click OK when finished. Now we want to test the settings, before continuing on…it’s just easier that way incase something was entered incorrectly. To make sure the settings are tested, check the box Test Account Settings by clicking the Next button. If you’ve entered everything in correctly, both tasks will be completed successfully and you can close out of the window. and begin using your account via Outlook 2010. You’ll get a final congratulations message you can close out of… And begin using your account via Outlook 2010. Conclusion Using IMAP allows you to synchronize email across multiple machines and devices. The IMAP feature in Gmail is free to use, and this should get you started using it with Outlook 2010. If you’re still using 2007 or just upgraded to it, check out our guide on how to use Gmail IMAP in Outlook 2007. Similar Articles Productive Geek Tips Add Your Gmail To Windows Live MailForce Outlook 2007 to Download Complete IMAP ItemsUse Gmail IMAP in Microsoft Outlook 2007Prevent Outlook with Gmail IMAP from Showing Duplicate Tasks in the To-Do BarSetting up Gmail IMAP Support for Windows Vista Mail TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Cool Looking Skins for Windows Media Player 12 Move the Mouse Pointer With Your Face Movement Using eViacam Boot Windows Faster With Boot Performance Diagnostics Create Ringtones For Your Android Phone With RingDroid Enhance Your Laptop’s Battery Life With These Tips Easily Search Food Recipes With Recipe Chimp

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  • What is the Oracle Utilities Application Framework?

    - by Anthony Shorten
    The Oracle Utilities Application Framework is a reusable, scalable and flexible java based framework which allows other products to be built, configured and implemented in a standard way. Note: Even though the Framework is built in java it can be integrated with COBOL based extensions for backward compatibility. When Oracle Utilities Customer Care & Billing was migrated from V1 to V2, it was decided that the technical aspects of that product be separated to allow for reuse and independence from technical issues. The idea was that all the technical aspects would be concentrated in this separate product (i.e. a framework) and allow all products using the framework to concentrate on delivering superior functionality. The product was named the Oracle Utilities Application Framework (oufw is the product code). The technical components are contained in the Oracle Utilities Application Framework which can be summarized as follows: Metadata - The Oracle Utilities Application Framework is responsible for defining and using the metadata to define the runtime behavior of the product. All the metadata definition and management is contained within the Oracle Utilities Application Framework. UI Management - The Oracle Utilities Application Framework is responsible for defining and rendering the pages and responsible for ensuring the pages are in the appropriate format for the locale. Integration - The Oracle Utilities Application Framework is responsible for providing the integration points to the architecture. Refer to the Oracle Utilities Application Framework Integration Overview for more details Tools - The Oracle Utilities Application Framework provides a common set of facilities and tools that can be used across all products. Technology - The Oracle Utilities Application Framework is responsible for all technology standards compliance, platform support and integration. There are a number of products from the Tax and Utilities Global Business Unit as well as from the Financial Services Global Business Unit that are built upon the Oracle Utilities Application Framework. These products require the Oracle Utilities Application Framework to be installed first and then the product itself installed onto the framework to complete the installation process. There are a number of key benefits that the Oracle Utilities Application Framework provides to these products: Common facilities - The Oracle Utilities Application Framework provides a standard set of technical facilities that mean that products can concentrate in the unique aspects of their markets rather than making technical decisions. Common methods of configuration - The Oracle Utilities Application Framework standardizes the technical configuration process for a product. Customers can effectively reuse the configuration process across products. Multi-lingual and Multi-platform - The Oracle Utilities Application Framework allows the products to be offered in more markets and across multiple platforms for maximized flexibility. Common methods of implementation - The Oracle Utilities Application Framework standardizes the technical aspects of a product implementation. Customers can effectively reuse the technical implementation process across products. Quicker adoption of new technologies - As new technologies and standards are identified as being important for the product line, they can be integrated centrally benefiting multiple products. Cross product reuse - As enhancements to the Oracle Utilities Application Framework are identified by a particular product, all products can potentially benefit from the enhancement. Note: Use of the Oracle Utilities Application Framework does not preclude the introduction of product specific technologies or facilities to satisfy market needs. The framework minimizes the need and assists in the quick integration of a new product specific piece of technology (if necessary). The Framework is not available as a product itself and is bundled with Tax and Utilities Global Business Unit prodicts. At the present time the following products are on the Framework: Oracle Utilities Customer Care And Billing (V2 and above) Oracle Enterprise Taxation Management (V2 and above) Oracle Utilities Business Intelligence (V2 and above) Oracle Utilities Mobile Workforice Management (V2 and above)

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  • Performance and Optimization Isn’t Evil

    - by Reed
    Donald Knuth is a fairly amazing guy.  I consider him one of the most influential contributors to computer science of all time.  Unfortunately, most of the time I hear his name, I cringe.  This is because it’s typically somebody quoting a small portion of one of his famous statements on optimization: “premature optimization is the root of all evil.” I mention that this is only a portion of the entire quote, and, as such, I feel that Knuth is being quoted out of context.  Optimization is important.  It is a critical part of every software development effort, and should never be ignored.  A developer who ignores optimization is not a professional.  Every developer should understand optimization – know what to optimize, when to optimize it, and how to think about code in a way that is intelligent and productive from day one. I want to start by discussing my own, personal motivation here.  I recently wrote about a performance issue I ran across, and was slammed by multiple comments and emails that effectively boiled down to: “You’re an idiot.  Premature optimization is the root of all evil.  This doesn’t matter.”  It didn’t matter that I discovered this while measuring in a profiler, and that it was a portion of my code base that can take “many hours to complete.”  Even so, multiple people instantly jump to “it’s premature – it doesn’t matter.” This is a common thread I see.  For example, StackOverflow has many pages of posts with answers that boil down to (mis)quoting Knuth.  In fact, just about any question relating to a performance related issue gets this quote thrown at it immediately – whether it deserves it or not.  That being said, I did receive some positive comments and emails as well.  Many people want to understand how to optimize their code, approaches to take, tools and techniques they can use, and any other advice they can discover. First, lets get back to Knuth – I mentioned before that Knuth is being quoted out of context.  Lets start by looking at the entire quote from his 1974 paper Structured Programming with go to Statements: “We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%. A good programmer will not be lulled into complacency by such reasoning, he will be wise to look carefully at the critical code; but only after that code has been identified.” Ironically, if you read Knuth’s original paper, this statement was made in the middle of a discussion of how Knuth himself had changed how he approaches optimization.  It was never a statement saying “don’t optimize”, but rather, “optimizing intelligently provides huge advantages.”  His approach had three benefits: “a) it doesn’t take long” … “b) the payoff is real”, c) you can “be less efficient in the other parts of my programs, which therefore are more readable and more easily written and debugged.” Looking at Knuth’s premise here, and reading that section of his paper, really leads to a few observations: Optimization is important  “he will be wise to look carefully at the critical code” Normally, 3% of your code – three lines out of every 100 you write, are “critical code” and will require some optimization: “we should not pass up our opportunities in that critical 3%” Optimization, if done well, should not be time consuming: “it doesn’t take long” Optimization, if done correctly, provides real benefits: “the payoff is real” None of this is new information.  People who care about optimization have been discussing this for years – for example, Rico Mariani’s Designing For Performance (a fantastic article) discusses many of the same issues very intelligently. That being said, many developers seem unable or unwilling to consider optimization.  Many others don’t seem to know where to start.  As such, I’m going to spend some time writing about optimization – what is it, how should we think about it, and what can we do to improve our own code.

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  • Something for the weekend - Whats the most complex query?

    - by simonsabin
    Whenever I teach about SQL Server performance tuning I try can get across the message that there is no such thing as a table. Does that sound odd, well it isn't, trust me. Rather than tables you need to consider structures. You have 1. Heaps 2. Indexes (b-trees) Some people split indexes in two, clustered and non-clustered, this I feel confuses the situation as people associate clustered indexes with sorting, but don't associate non clustered indexes with sorting, this is wrong. Clustered and non-clustered indexes are the same b-tree structure(and even more so with SQL 2005) with the leaf pages sorted in a linked list according to the keys of the index.. The difference is that non clustered indexes include in their structure either, the clustered key(s), or the row identifier for the row in the table (see http://sqlblog.com/blogs/kalen_delaney/archive/2008/03/16/nonclustered-index-keys.aspx for more details). Beyond that they are the same, they have key columns which are stored on the root and intermediary pages, and included columns which are on the leaf level. The reason this is important is that this is how the optimiser sees the world, this means it can use any of these structures to resolve your query. Even if your query only accesses one table, the optimiser can access multiple structures to get your results. One commonly sees this with a non-clustered index scan and then a key lookup (clustered index seek), but importantly it's not restricted to just using one non-clustered index and the clustered index or heap, and that's the challenge for the weekend. So the challenge for the weekend is to produce the most complex single table query. For those clever bods amongst you that are thinking, great I will just use lots of xquery functions, sorry these are the rules. 1. You have to use a table from AdventureWorks (2005 or 2008) 2. You can add whatever indexes you like, but you must document these 3. You cannot use XQuery, Spatial, HierarchyId, Full Text or any open rowset function. 4. You can only reference your table once, i..e a FROM clause with ONE table and no JOINs 5. No Sub queries. The aim of this is to show how the optimiser can use multiple structures to build the results of a query and to also highlight why the optimiser is doing that. How many structures can you get the optimiser to use? As an example create these two indexes on AdventureWorks2008 create index IX_Person_Person on Person.Person (lastName, FirstName,NameStyle,PersonType) create index IX_Person_Person on Person.Person(BusinessentityId,ModifiedDate)with drop_existing    select lastName, ModifiedDate   from Person.Person  where LastName = 'Smith' You will see that the optimiser has decided to not access the underlying clustered index of the table but to use two indexes above to resolve the query. This highlights how the optimiser considers all storage structures, clustered indexes, non clustered indexes and heaps when trying to resolve a query. So are you up to the challenge for the weekend to produce the most complex single table query? The prize is a pdf version of a popular SQL Server book, or a physical book if you live in the UK.  

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  • T-SQL Improvements And Data Types in ms sql 2008

    - by Aamir Hasan
     Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

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  • Silverlight Cream for March 24, 2010 -- #819

    - by Dave Campbell
    In this Issue: Nokola, Tim Heuer, Christian Schormann, Brad Abrams, David Kelley, Phil Middlemiss, Michael Klucher, Brandon Watson, Kunal Chowdhury, Jacek Ciereszko, and Unni. Shoutouts: Michael Klucher has a short post up For Love of the Game (Development)…, where he's looking for some input from the developer community. Shawn Hargreaves has a link post up of all the Windows Phone MIX10 presentations Chris Cavanagh has a Soft-Body Physics for Windows Phone 7 post up that goes along with one he did 1-1/2 years ago! Jeff Weber posted An Open Letter To Microsoft Regarding The Silverlight Game Development Community Pete Brown posted his MIX10 Recap ... lots of information, and discussion of what he was up to ... I liked the Trivia app Pete... glad to hear that was yours :) I've changed my mind and added a WP7 tag to SilverlightCream. I'll straighten out all the Mobile plus Silverlight links to point at the WP7 tab hopefully tonight. From SilverlightCream.com: EasyPainter Source Pack 3: Adorners, Mouse Cursors and Frames Nokola has been busy with EasyPainter adding in Custom, Extensible Mouse Cursors and Customizable Adorners with extensible adorner frames, and best of all... all with source code! Simulate Geo Location in Silverlight Windows Phone 7 emulator Among the things we don't have in our WP7 emulators is Geo Location... Tim Heuer comes to the rescue with a simulator for it... too cool, Tim! Blend 4: About Path Layout, Part II Christian Schormann is back with Part 2 of his tutorial sequence on the new Path Layout. Really good info and definitely cool presentations of the control. Silverlight 4 + RIA Services - Ready for Business: Exposing OData Services Brad Abrams continues his series with a post on exposing OData services. This looks like a great tutorial on the topic... will probably resolve some questions I've been having :) No Silverlight and Preloader Experience(ish) - in 10 seconds... David Kelley exposes the code he uses on his site, designed to be friendly to Silverlight and non-Silverlight users alike. Merged Dictionaries of Style Resources and Blend Phil Middlemiss has a nice article up on Merged Dictionaries and using multiple resource dictionaries that the app chooses, but also be compatible with Prism and Blend while not eating your system resources out of house and home. XNA Game Studio and Windows Phone Emulator Compatibility Michael Klucher has a definitive post up about getting your XNA and system up-to-speed for WP7... a must-read if you've been running any of the other XNA drops. Windows Phone 7 301 Redirect Bug Brandon Watson reports a 301 Redirect bug on WP7 ... see the code and how he got it, then follow along as he explains all the debug paths he took and what the resolution (?) really is :) Silverlight 4: How to use the new Printing API? Kunal Chowdhury has a tutorial up on printing with Silverlight 4 RC... from the project layout to printing and then printing a smaller section... all good Printing problem in Silverlight 4.0 RC - loading images in code behind Jacek Ciereszko also is writing about printing, and in his case he had problems with loading an image dynamically and printing it... plus he provides a solution to the 'blank page' problem. ToolboxExampleAttribute - a new extension point in Blend 4 (and a few other extensibility related changes) Unni has an article up about Expression Blend 4's new ToolboxExampleAttribute which allow you to have multiple examples of the same type resulting in different XAML produced. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone    MIX10

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  • SQL SERVER – Merge Operations – Insert, Update, Delete in Single Execution

    - by pinaldave
    This blog post is written in response to T-SQL Tuesday hosted by Jorge Segarra (aka SQLChicken). I have been very active using these Merge operations in my development. However, I have found out from my consultancy work and friends that these amazing operations are not utilized by them most of the time. Here is my attempt to bring the necessity of using the Merge Operation to surface one more time. MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. One of the most important advantages of MERGE statement is that the entire data are read and processed only once. In earlier versions, three different statements had to be written to process three different activities (INSERT, UPDATE or DELETE); however, by using MERGE statement, all the update activities can be done in one pass of database table. I have written about these Merge Operations earlier in my blog post over here SQL SERVER – 2008 – Introduction to Merge Statement – One Statement for INSERT, UPDATE, DELETE. I was asked by one of the readers that how do we know that this operator was doing everything in single pass and was not calling this Merge Operator multiple times. Let us run the same example which I have used earlier; I am listing the same here again for convenience. --Let’s create Student Details and StudentTotalMarks and inserted some records. USE tempdb GO CREATE TABLE StudentDetails ( StudentID INTEGER PRIMARY KEY, StudentName VARCHAR(15) ) GO INSERT INTO StudentDetails VALUES(1,'SMITH') INSERT INTO StudentDetails VALUES(2,'ALLEN') INSERT INTO StudentDetails VALUES(3,'JONES') INSERT INTO StudentDetails VALUES(4,'MARTIN') INSERT INTO StudentDetails VALUES(5,'JAMES') GO CREATE TABLE StudentTotalMarks ( StudentID INTEGER REFERENCES StudentDetails, StudentMarks INTEGER ) GO INSERT INTO StudentTotalMarks VALUES(1,230) INSERT INTO StudentTotalMarks VALUES(2,255) INSERT INTO StudentTotalMarks VALUES(3,200) GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Merge Statement MERGE StudentTotalMarks AS stm USING (SELECT StudentID,StudentName FROM StudentDetails) AS sd ON stm.StudentID = sd.StudentID WHEN MATCHED AND stm.StudentMarks > 250 THEN DELETE WHEN MATCHED THEN UPDATE SET stm.StudentMarks = stm.StudentMarks + 25 WHEN NOT MATCHED THEN INSERT(StudentID,StudentMarks) VALUES(sd.StudentID,25); GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Clean up DROP TABLE StudentDetails GO DROP TABLE StudentTotalMarks GO The Merge Join performs very well and the following result is obtained. Let us check the execution plan for the merge operator. You can click on following image to enlarge it. Let us evaluate the execution plan for the Table Merge Operator only. We can clearly see that the Number of Executions property suggests value 1. Which is quite clear that in a single PASS, the Merge Operation completes the operations of Insert, Update and Delete. I strongly suggest you all to use this operation, if possible, in your development. I have seen this operation implemented in many data warehousing applications. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Joins, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Merge

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