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  • Ubiquitous Language and Custom types

    - by EdvRusj
    Note that my question is referring to those attributes that even on their own already represent a concept ( ie on their own provide a cohesive meaning ). Thus such attribute needs no additional functional support and as such is self-contained. I'm also well-aware that even with self-contained attributes the custom types may prove beneficial ( for example, they give the ability to add new behavior later, when business requirements change ). Thus, my question focuses only on whether custom types for self-contained attributes really enrich Ubiquitous Language UL a) I've read that in most cases, even simple, self-contained attributes should have custom, more descriptive types rather than basic value types ( double, string ... ), because among other things, descriptive types add to the UL, while the use of basic types instead weakens the language. I understand the importance of UL, but how does having a basic type for a self-contained attribute weaken the language, since with self-contained attributes the name of the attribute already adequately describes the concept and thus contributes to the UL vocabulary? For example, the term person_age already adequately explains the concept of quantifying the number of years a person has: class Person { string person_age; } so what could we possibly gain by also introducing the term ThingAge to the UL: class person { ThingAge person_age; } thanks

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  • Building a complete program?

    - by Bob
    Reading books, watching videos, and reviewing tutorials is all very easy. Taking notes and actually learning the material may be slightly harder, but even then, anyone with a decent brain and a fair amount of interest, it's easy enough (not to mention, fun). The thing is, it doesn't really prepare you to write a full program or website. Let's say you're those teens (only in highschool, no true (college level) computer science or programming courses, and no real world experience), and you come out with Groupon. Or even Mark Zuckerburg, sure he was a genius, and he was a very capable programmer... but how? How do you recommend that people who are not necessarily new to programming, but new to programming real applications and real programmers go about developing it? What is the "development process" - especially for single programmers (or maybe 2-3 teens)? Also, as far as web development goes, what is the process? Was something like Facebook or Groupon written with a framework (like CodeIgniter or Zend for PHP)? Or do they develop their own frameworks? I'm not asking how to come up with a great idea, but how to implement great ideas in an effective way? Does anyone have advice? I've read a couple of books on both C and C++ (primarily the C Programming Language and the C++ Programming Language) and taken AP Computer Science (as well as read a few additional books on Java and OOP). I also have read a few tutorials on PHP (and CodeIgniter) and Python. But I'm still in highschool, and I'm technically not even old enough to work at an internship for a few more months.

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  • The SQL Server Setup Portal

    - by BuckWoody
    One of the tasks that takes a long time for the data professional is setting up SQL Server. No, it isn’t that difficult to slide a DVD in a drive and click “Setup” but the overall process of planning the hardware and software environment, making decisions for high-availability, security and dozens of other choices can make the process more difficult. And then, of course, there are the inevitable issues that arise. Microsoft supports literally hundreds and even thousands of combinations of hardware and software drivers from vendors you’ve never even heard of. Making all of that work together is a small miracle, so things are bound to arise that you need to deal with. So, to help you out, we’ve designed a new “SQL Server Setup Portal”. It’s a one-stop-shop for everything you need to know about planning and setting up SQL Server. As time goes on you’ll see even more content added. There are already whitepapers, videos, and multiple places to search on everything from topic names to error codes. So go check it out – and if you have to do a lot of SQL Server Setups – and especially if you don’t – bookmark it as a favorite! Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Second Monitor Detected, but not receiving a signal after upgrading to 12.04

    - by user62458
    After I upgraded to 12.04, my second monitor is detected (in display settings), but will not power on. I have scoured the Internet and forums for a solution and I can't find anything. I have found a couple people with the same problem, but never a solution for it. I am no expert, but I'm certainly not a noob. My computer uses AMD Radeon 6250 graphics, but I do NOT want to use the proprietary graphics drivers. They refuse to work properly with my second monitor (they ATI drivers will only mirror screens, and I've done everything to try to fix it, and I DON't want mirrored screens) Not to mention that the default open-source video drivers seem to work much better than the proprietary anyway! Again, Ubuntu's default video drivers work fine, and they even DETECT the second monitor (Dell 19'). I can drag stuff off the screen and put it on the 'space' of the second monitor and even a screen-shot shows that there are two monitors active; but the monitor is OFF. It will not power on. It goes into 'power-save' mode because it is not receiving a signal. For some reason it is not getting the signal to power on, even though Ubuntu thinks the monitor is working properly. I had this working fine on my Sony VAIO yesterday (with Radeon graphics/default Ubuntu video drivers). I upgraded to a Samsung Series 3 and now I have this issue. I can't for the life of me figure out why the monitor is connected, detected and I have screen space for the monitor, but the screen won't turn on! XRANDR Output: Screen 0: minimum 320 x 200, current 1366 x 768, maximum 8192 x 8192 VGA-0 connected (normal left inverted right x axis y axis) 1440x900 59.9 + 75.0 1280x1024 75.0 60.0 1152x864 75.0 1024x768 75.1 70.1 60.0 832x624 74.6 800x600 72.2 75.0 60.3 56.2 640x480 72.8 75.0 66.7 60.0 720x400 70.1 LVDS connected 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 194mm 1366x768 60.1*+ 1280x720 59.9 1152x768 59.8 1024x768 59.9 800x600 59.9 848x480 59.7 720x480 59.7 640x480 59.4 HDMI-0 disconnected (normal left inverted right x axis y axis)

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  • Cry Engine 3 vs UDK

    - by Daniele Riccardelli
    I'm new here and I hope that other people may find this question interesting. Me and a bunch of guys from my University are thinking about getting started in game development, but, even though the game design is kind of ready, we are stucked at the point "which Engine should we choose". At first, we were thinking about Unity3D Free, in particular because we are pretty familiar with C# and, even better, it's completely free, but on the other hand there are some cons like no dynamic shadowing that make the realization of our game kinda hard. So, we are thinking about moving either to UDK or Cry Engine, since they are not as expensive as Unity3D Pro (at least before the game deployment) . The thing we are worried the most, though, is that we are kind of scared about the support for team work(i mean, that we might find it hard to coordinate our efforts without software support), since in Unity3D the team features are part of purchasable content, and we are not interested in paying that much for a project we are not even sure we can complete. So, finally, I hope one of you knows the mentioned engines enough to give us a tip telling which one offers better team features and is advisable for guys that have barely worked before on videogames but have good object oriented programming skills. Probably might be helpful for your suggestion, if i say that our game is an exploration game. Thanks to anybody who's going to answer.

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  • How exactly does app ranking work?

    - by qweasdzxc1
    So I've been in the app industry for around half a year and I still don't know how exactly ranking higher for your app will help increase downloads. That sounds like a question with an obvious answer but this is what's going through my mind so hear me out: Unless your app is ranked within the top 100, no one can see it in the featured categories. So even if my app jumped from 400th to 300th place, would there really even be a difference in downloads? And I'm saying 400th to 300th in ranking in my specific category. Indie developers like me don't even come close to ranking for the overall category. So far, the only usefulness of trying to get a higher rank is to get featured or something like that, but big companies have tons of money to throw on marketing...so the chances of any indie developer getting featured is rare. The only thing that I can see ranking being good for is to rank for your keywords so that when someone searches for that word, your app will hopefully appear in the top 10-25 results. Can anyone confirm my thoughts or add anything else that I might have missed out on? How exactly do users find your app if you're not in the top 100 app in your category?

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  • Why is a software development life-cycle so inefficient?

    - by user87166
    Currently the software development lifecycle followed in the IT company I work at is: The "Business" works with a solution manager to build a Business Requirement document The solution manager works with the Program manager to build a Functional Spec The PM works with the engineering lead to develop a release plan and with the engineering team to develop technical specifications If there are any clarifications required, developers contact the PM who contacts the solution manager who contacts the business and all the way back introducing a latency of nearly 24 hours and massive email chains for any clarifications By the time the tech spec is made, nearly 1 month has passed in back and forth Now, 2 weeks go to development while the test writes test cases Code is dropped formally to test, test starts raising bugs. Even if there is 1 root cause for 10 different issues, and its an easily fixed one, developers are not allowed to give fresh code to test for the next 1 week. After 2-3 such drops to test the code is given to the ops team as a "golden drop" ( 2 months passed from the beginning) Ops team will now deploy the code in a staging environment. If it runs stable for a week, it will be promoted to UAT and after 2 weeks of that it will be promoted to prod. If there are any bugs found here, well, applying for a visa requires less paperwork This entire process is followed even if a single SSRS report is to be released. How do other companies process such requirements? I'm wondering why, the business cannot just drop the requirements to developers, developers build and deploy to UAT themselves, expose it to the business who raise functional bugs and after fixing those promote to prod. (even for more complex stuff)

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  • How much a programmer should read in order to keep himself updated? [closed]

    - by anything
    There are lots of technical books available. Below are few links which lists some good books If you could only have one programming related book on your bookshelf what would it be and why? What non-programming books should a programmer read to help develop programming/thinking skills? Best books on the theory and practice of software architecture? http://stackoverflow.com/questions/1711/what-is-the-single-most-influential-book-every-programmer-should-read ... and the list can go on and on and on. It will be really difficult to read all of the above mentioned books. I am not sure if its even possible for anyone to do that. Even if you filter it based on one's area of interest or work, list is still very large. .. and the technology keeps on changing (even more books :-( ) So, my question is how much a programmer should read lets say per year? How much hours one should put in such activities to keep oneself up to date? How do we find out the time required? PS: Average programmer reads less than one book per year (Code complete). What about the good programmers?

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  • How to troubleshoot GPU freezes?

    - by dlsmith2
    So in advance I'll just say I am a total linux newbie, so be kind. I just downloaded Ubuntu 11.10 and this is my first experience with Linux. I enjoy it so far and actually enjoy it except for when my computer freezes. This has been quite often so far. I've done a little research and it seems my problem is with the GPU. When it does freeze I can move the cursor but cannot click on anything. I also cannot run Alt+F2 xkill. So my only previous experience has been with Windows and I would normally solve an issue like this with Ctrl+Alt+Delete and just shut down the offending program. I do not know how to do this in Ubuntu and not even sure this would even work. Please help me if you can, how do I deal with a freeze without having to resort to a hard shutdown, I cannot seem to run the computer over one hour without experiencing this issue. I tried accessing my GRUB menu on startup but I can't even seem to do that. Also the only real program I have been running whenever this happens seems to be Firefox. Thank you, appreciate any help. After running lspci | grep VGA command prompt: 00:12.0 VGA compatible controller: nVidia Corporation C67 [GeForce 7150M / nForce 630M] (rev a2)*****

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  • How to access Ubuntu Server from local PC?

    - by Roland
    Today I installed my first web server, which is Ubuntu 12.04 LTS. I got Apache, PHP and MySql working, there is even MyPHPAdmin! Everything is working fine on that PC, but the problem is that I have no idea how to connect to this server from my PC. Just to clarify- I got one PC that I work on and got another one, which has Ubuntu Server running. I even managed to connect them through the router, which I made to work as a switch. I can see the Ubuntu Server on my Windows PC in "Network", but it's empty, I can't see any files. I tried to share a folder etc/www on Server, but it shows an error saying something about right, that I'm not this folder's owner. I guess I'm not doing the right thing at all, am I? Even if I could see shared folder on my Windows PC- I would still be not able to type "somedomain.com" on Windows PC and access for example index.php or MySql database. So, the question is- how do I configure Ubuntu Server to be accessible from Windows PC?

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  • Isn't Java a quite good choice for desktop applications?

    - by tactoth
    At present most applications are still developed with C++, painfully. Lack of portability, in compatible libraries, memory leaks, slow compilation, and poor productivity. Even if you pick only a single from these shortages, it's still a big headache. However the surprising truth is that C++ remains the first choice for desktop applications. Compared to C++ Java has lots of advantages. The success in server side development shows that the language itself is good, Swing is also thought to be as programmer friendly as the highly recognized QT framework (No, never say even a single word about MFC!). All the disadvantages of C++ listed above has a solution in Java. "Performance!", Well that might still be the problem but to my experience it's a slight problem. I'd been using Java to decode some screen video and generate key frames. The video has a duration of more than 1 hour. The time spent on an average machine is just 1 minute. With C++ I don't expect even faster speed. In recent days there are many news on the JIT performance improvements, that make us feel Java is gradually becoming very suitable for desktop development, without people realizing it. Isn't it?

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  • High-level description of how experimental C++ features are developed?

    - by Praxeolitic
    Herb Sutter in a video answers a question about the concepts proposal considered for C++11 and from his remarks it sounds like multiple groups offered prototype implementations but all of them left concerns about slow compile times. The comment surprised me because it suggests that, at least in some cases, the prototypes being developed are not just proofs of concept -- they're even expected to perform. All the work that must take has me curious. For mature languages, especially C++, how are experimental language features developed? Is it much different from developing a compiler that implements a standard? Does a developer have a sense of if it will work and perform or even if it ever could? What are the most time consuming parts and are any parts surprisingly easier than one might expect? The question is not what does the C++ standards committee do, but rather the part that comes before. When an experimental implementation for a proposal is being put together and there aren't any completely solidified rules, how is the sausage made? I'm not a professional compiler developer nor do I expect answers with step by step accounts. I'd like a high-level idea of how this would be done or if there are any general patterns at all. I don't know what to expect from the answers but even if there are no rules to the process and the small number of people who do this just cowboy it and then, for stuff that worked out, write up the "official version" as a proposal, that answer would still be informative.

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  • Why does my system slow down or freeze when there is heavy disk activity?

    - by user72270
    Im a first-time user to Ubuntu-12.04 with WUBI installation. My NoteBook Information : Dell vostro 3450 : i5 2410m, 3 gb ram, intel hd3000, amd 6630m hybrid. Surfing and playing games works flawlessly, however, I'm having huge problems when installing applications and generally copying and moving files. When doing so, system is significantly slower and freezes quite often (Firefox gets bluish, sometimes even black n white). I would say that Ubuntu allocates too much resources on file transfers and installing, but even these tasks are very slow. Here is very specific example : today, i tried to move 6 GB file from win 7 installation. It was good at first, i jumped to firefox but after a while firefox started to randomly turn bluish and mouse was randomly stopping working. It was gradually worse and worse and it got to a point when firefox black n whited and mouse wasn't working at all. I raged and went for some meal, when i got back screen was black. It probably unlogged me due to inactivity, when i pushed random button to bring screen to life i had to wait few minutes to let it show me only my screen background. No log in screen, just background and working mouse. NoteBook fan was working at 100 % so I assumed that file transfer was going on and I left it to work. Nothing then changed for a full hour so I hard rebooted it. File transfer unsuccessful, It transfered hardly 2 gigs. Is this normal ? What to do in these situations ? It didn't let me load system manager and not even terminal. Thanks.

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  • Desktop Fun: Merry Christmas Fonts

    - by Asian Angel
    Christmas will soon be here and there are lots of cards, invitations, gift tags, photos, and more to prepare beforehand. To help you get ready we have gathered together a great collection of fun holiday fonts to help turn those ordinary looking holiday items into extraordinary looking ones. Note: To manage the fonts on your Windows 7, Vista, & XP systems see our article here. Oldchristmas Download Holly Download Christmas Flakes *includes two font types Download Frosty Download Kingthings Christmas Download Candy Time Download BodieMF Holly Download Snowfall Download Snowflake Letters Download Hultog Snowdrift Download AlphaShapes Xmas Trees Download Christmas Tree Download PF Wreath Download Snowy Caps Download PF Snowman *includes three font types Note: Shown in all capital letters here. Download BJF Holly Bells Download Christbaumkugeln Download Xmas Lights Download XmasDings *includes 62 individual characters Note: This group represents A – Z in all capital letters. Note: This group represents A – Z in all lower case letters. Note: This group represents the numbers 0 – 9. Download WWFlakes *includes 62 individual characters Note: This group represents A – Z in all capital letters. Note: This group represents A – Z in all lower case letters. Note: This group represents the numbers 0 – 9. Download For Christmas Card creating fun and a great way to use your new fonts see our MS Word Christmas Card project series here. Design and Print Your Own Christmas Cards in MS Word, Part 1 Design and Print Your Own Christmas Cards in MS Word, Part 2: How to Print Want more great ways to customize your computer? Then be certain to look through our Desktop Fun section. Latest Features How-To Geek ETC The How-To Geek Holiday Gift Guide (Geeky Stuff We Like) LCD? LED? Plasma? The How-To Geek Guide to HDTV Technology The How-To Geek Guide to Learning Photoshop, Part 8: Filters Improve Digital Photography by Calibrating Your Monitor Our Favorite Tech: What We’re Thankful For at How-To Geek The How-To Geek Guide to Learning Photoshop, Part 7: Design and Typography Happy Snow Bears Theme for Chrome and Iron [Holiday] Download Full Command and Conquer: Tiberian Sun Game for Free Scorched Cometary Planet Wallpaper Quick Fix: Add the RSS Button Back to the Firefox Awesome Bar Dropbox Desktop Client 1.0.0 RC for Windows, Linux, and Mac Released Hang in There Scrat! – Ice Age Wallpaper

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  • ASP.NET Controls – CommunityServer Captcha ControlAdapter, a practical case

    - by nmgomes
    The ControlAdapter is available since .NET framework version 2.0 and his main goal is to adapt and customize a control render in order to achieve a specific behavior or layout. This customization is done without changing the base control. A ControlAdapter is commonly used to custom render for specific platforms like Mobile. In this particular case the ControlAdapter was used to add a specific behavior to a Control. In this  post I will use one adapter to add a Captcha to all WeblogPostCommentForm controls within pontonetpt.com CommunityServer instance. The Challenge The ControlAdapter complexity is usually associated with the complexity/structure of is base control. This case is precisely one of those since base control dynamically load his content (controls) thru several ITemplate. Those of you who already played with ITemplate knows that while it is an excellent option for control composition it also brings to the table a big issue: “Controls defined within a template are not available for manipulation until they are instantiated inside another control.” While analyzing the WeblogPostCommentForm control I found that he uses the ITemplate technique to compose it’s layout and unfortunately I also found that the template content vary from theme to theme. This could have been a problem but luckily WeblogPostCommentForm control template content always contains a submit button with a well known ID (at least I can assume that there are a well known set of IDs). Using this submit button as anchor it’s possible to add the Captcha controls in the correct place. Another important finding was that WeblogPostCommentForm control inherits from the WrappedFormBase control which is the base control for all CommunityServer input forms. Knowing this inheritance link the main goal has changed to became the creation of a base ControlAdapter that  could be extended and customized to allow adding Captcha to: post comments form contact form user creation form. And, with this mind set, I decided to used the following ControlAdapter base class signature :public abstract class WrappedFormBaseCaptchaAdapter<T> : ControlAdapter where T : WrappedFormBase { }Great, but there are still many to do … Captcha The Captcha will be assembled with: A dynamically generated image with a set of random numbers A TextBox control where the image number will be inserted A Validator control to validate whether TextBox numbers match the image numbers This is a common Captcha implementation, is not rocket science and don’t bring any additional problem. The main problem, as told before, is to find the correct anchor control to ensure a correct Captcha control injection. The anchor control can vary by: target control  theme Implementation To support this dynamic scenario I choose to use the following implementation:private List<string> _validAnchorIds = null; protected virtual List<string> ValidAnchorIds { get { if (this._validAnchorIds == null) { this._validAnchorIds = new List<string>(); this._validAnchorIds.Add("btnSubmit"); } return this._validAnchorIds; } } private Control GetAnchorControl(T wrapper) { if (this.ValidAnchorIds == null || this.ValidAnchorIds.Count == 0) { throw new ArgumentException("Cannot be null or empty", "validAnchorNames"); } var q = from anchorId in this.ValidAnchorIds let anchorControl = CSControlUtility.Instance().FindControl(wrapper, anchorId) where anchorControl != null select anchorControl; return q.FirstOrDefault(); } I can now, using the ValidAnchorIds property, configure a set of valid anchor control  Ids. The GetAnchorControl method searches for a valid anchor control within the set of valid control Ids. Here, some of you may question why to use a LINQ To Objects expression, but the important here is to notice the usage of CSControlUtility.Instance().FindControl CommunityServer method. I want to build on top of CommunityServer not to reinvent the wheel. Assuming that an anchor control was found, it’s now possible to inject the Captcha at the correct place. This not something new, we do this all the time when creating server controls or adding dynamic controls:protected sealed override void CreateChildControls() { base.CreateChildControls(); if (this.IsCaptchaRequired) { T wrapper = base.Control as T; if (wrapper != null) { Control anchorControl = GetAnchorControl(wrapper); if (anchorControl != null) { Panel phCaptcha = new Panel {CssClass = "CommonFormField", ID = "Captcha"}; int index = anchorControl.Parent.Controls.IndexOf(anchorControl); anchorControl.Parent.Controls.AddAt(index, phCaptcha); CaptchaConfiguration.DefaultProvider.AddCaptchaControls( phCaptcha, GetValidationGroup(wrapper, anchorControl)); } } } } Here you can see a new entity in action: a provider. This is a CaptchaProvider class instance and is only goal is to create the Captcha itself and do everything else is needed to ensure is correct operation.public abstract class CaptchaProvider : ProviderBase { public abstract void AddCaptchaControls(Panel captchaPanel, string validationGroup); } You can create your own specific CaptchaProvider class to use different Captcha strategies including the use of existing Captcha services  like ReCaptcha. Once the generic ControlAdapter was created became extremely easy to created a specific one. Here is the specific ControlAdapter for the WeblogPostCommentForm control:public class WeblogPostCommentFormCaptchaAdapter : WrappedFormBaseCaptchaAdapter<WrappedFormBase> { #region Overriden Methods protected override List<string> ValidAnchorIds { get { List<string> validAnchorNames = base.ValidAnchorIds; validAnchorNames.Add("CommentSubmit"); return validAnchorNames; } } protected override string DefaultValidationGroup { get { return "CreateCommentForm"; } } #endregion Overriden Methods } Configuration This is the magic step. Without changing the original pages and keeping the application original assemblies untouched we are going to add a new behavior to the CommunityServer application. To glue everything together you must follow this steps: Add the following configuration to default.browser file:<?xml version='1.0' encoding='utf-8'?> <browsers> <browser refID="Default"> <controlAdapters> <!-- Adapter for the WeblogPostCommentForm control in order to add the Captcha and prevent SPAM comments --> <adapter controlType="CommunityServer.Blogs.Controls.WeblogPostCommentForm" adapterType="NunoGomes.CommunityServer.Components.WeblogPostCommentFormCaptchaAdapter, NunoGomes.CommunityServer" /> </controlAdapters> </browser> </browsers> Add the following configuration to web.config file:<configuration> <configSections> <!-- New section for Captcha providers configuration --> <section name="communityServer.Captcha" type="NunoGomes.CommunityServer.Captcha.Configuration.CaptchaSection" /> </configSections> <!-- Configuring a simple Captcha provider --> <communityServer.Captcha defaultProvider="simpleCaptcha"> <providers> <add name="simpleCaptcha" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProvider, NunoGomes.CommunityServer" imageUrl="~/captcha.ashx" enabled="true" passPhrase="_YourPassPhrase_" saltValue="_YourSaltValue_" hashAlgorithm="SHA1" passwordIterations="3" keySize="256" initVector="_YourInitVectorWithExactly_16_Bytes_" /> </providers> </communityServer.Captcha> <system.web> <httpHandlers> <!-- The Captcha Image handler used by the simple Captcha provider --> <add verb="GET" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </httpHandlers> </system.web> <system.webServer> <handlers accessPolicy="Read, Write, Script, Execute"> <!-- The Captcha Image handler used by the simple Captcha provider --> <add verb="GET" name="captcha" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </handlers> </system.webServer> </configuration> Conclusion Building a ControlAdapter can be complex but the reward is his ability to allows us, thru configuration changes, to modify an application render and/or behavior. You can see this ControlAdapter in action here and here (anonymous required). A complete solution is available in “CommunityServer Extensions” Codeplex project.

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  • How to find and fix performance problems in ORM powered applications

    - by FransBouma
    Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

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  • Upcoming Webcast on June 17: Gain Control Over Your Financial Close

    - by Theresa Hickman
    Accenture and Oracle EPM (Enterprise Perfromance Management) and GRC (Governance, Risk, and Compliance) will be hosting a live webcast called "Gain Control Over Your Financial Close - Confidence in the Process, Trust in the Numbers." When: Thursday, June 17, 2010 Time: 9:00am PST (Noon EST) Don't miss this chance to find out how you could optimize the financial close process and transform the speed, quality and integrity of your financial reporting. For more information and to register for this event, see this webpage.

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  • What’s New in Delphi XE6 Regular Expressions

    - by Jan Goyvaerts
    There’s not much new in the regular expression support in Delphi XE6. The big change that should be made, upgrading to PCRE 8.30 or later and switching to the pcre16 functions that use UTF-16, still hasn’t been made. XE6 still uses PCRE 7.9 and thus continues to require conversion from the UTF-16 strings that Delphi uses natively to the UTF-8 strings that older versions of PCRE require. Delphi XE6 does fix one important issue that has plagued TRegEx since it was introduced in Delphi XE. Previously, TRegEx could not find zero-length matches. So a regex like (?m)^ that should find a zero-length match at the start of each line would not find any matches at all with TRegEx. The reason for this is that TRegEx uses TPerlRegEx to do the heavy lifting. TPerlRegEx sets its State property to [preNotEmpty] in its constructor, which tells it to skip zero-length matches. This is not a problem with TPerlRegEx because users of this class can change the State property. But TRegEx does not provide a way to change this property. So in Delphi XE5 and prior, TRegEx cannot find zero-length matches. In Delphi XE6 TPerlRegEx’s constructor was changed to initialize State to the empty set. This means TRegEx is now able to find zero-length matches. TRegex.Replace() using the regex (?m)^ now inserts the replacement at the start of each line, as you would expect. If you use TPerlRegEx directly, you’ll need to set State to [preNotEmpty] in your own code if you relied on its behavior to skip zero-length matches. You will need to check existing applications that use TRegEx for regular expressions that incorrectly allow zero-length matches. In XE5 and prior, TRegEx using \d* would match all numbers in a string. In XE6, the same regex still matches all numbers, but also finds a zero-length match at each position in the string. RegexBuddy 4 warns about zero-length matches on the Create panel if you set it to Detailed mode. At the bottom of the regex tree there will be a node saying either “your regular expression may find zero-length matches” or “zero-length matches will be skipped” depending on whether your application allows zero-length matches (XE6 TRegEx) or not (XE–XE5 TRegEx).

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  • SQL SERVER – Guest Post – Architecting Data Warehouse – Niraj Bhatt

    - by pinaldave
    Niraj Bhatt works as an Enterprise Architect for a Fortune 500 company and has an innate passion for building / studying software systems. He is a top rated speaker at various technical forums including Tech·Ed, MCT Summit, Developer Summit, and Virtual Tech Days, among others. Having run a successful startup for four years Niraj enjoys working on – IT innovations that can impact an enterprise bottom line, streamlining IT budgets through IT consolidation, architecture and integration of systems, performance tuning, and review of enterprise applications. He has received Microsoft MVP award for ASP.NET, Connected Systems and most recently on Windows Azure. When he is away from his laptop, you will find him taking deep dives in automobiles, pottery, rafting, photography, cooking and financial statements though not necessarily in that order. He is also a manager/speaker at BDOTNET, Asia’s largest .NET user group. Here is the guest post by Niraj Bhatt. As data in your applications grows it’s the database that usually becomes a bottleneck. It’s hard to scale a relational DB and the preferred approach for large scale applications is to create separate databases for writes and reads. These databases are referred as transactional database and reporting database. Though there are tools / techniques which can allow you to create snapshot of your transactional database for reporting purpose, sometimes they don’t quite fit the reporting requirements of an enterprise. These requirements typically are data analytics, effective schema (for an Information worker to self-service herself), historical data, better performance (flat data, no joins) etc. This is where a need for data warehouse or an OLAP system arises. A Key point to remember is a data warehouse is mostly a relational database. It’s built on top of same concepts like Tables, Rows, Columns, Primary keys, Foreign Keys, etc. Before we talk about how data warehouses are typically structured let’s understand key components that can create a data flow between OLTP systems and OLAP systems. There are 3 major areas to it: a) OLTP system should be capable of tracking its changes as all these changes should go back to data warehouse for historical recording. For e.g. if an OLTP transaction moves a customer from silver to gold category, OLTP system needs to ensure that this change is tracked and send to data warehouse for reporting purpose. A report in context could be how many customers divided by geographies moved from sliver to gold category. In data warehouse terminology this process is called Change Data Capture. There are quite a few systems that leverage database triggers to move these changes to corresponding tracking tables. There are also out of box features provided by some databases e.g. SQL Server 2008 offers Change Data Capture and Change Tracking for addressing such requirements. b) After we make the OLTP system capable of tracking its changes we need to provision a batch process that can run periodically and takes these changes from OLTP system and dump them into data warehouse. There are many tools out there that can help you fill this gap – SQL Server Integration Services happens to be one of them. c) So we have an OLTP system that knows how to track its changes, we have jobs that run periodically to move these changes to warehouse. The question though remains is how warehouse will record these changes? This structural change in data warehouse arena is often covered under something called Slowly Changing Dimension (SCD). While we will talk about dimensions in a while, SCD can be applied to pure relational tables too. SCD enables a database structure to capture historical data. This would create multiple records for a given entity in relational database and data warehouses prefer having their own primary key, often known as surrogate key. As I mentioned a data warehouse is just a relational database but industry often attributes a specific schema style to data warehouses. These styles are Star Schema or Snowflake Schema. The motivation behind these styles is to create a flat database structure (as opposed to normalized one), which is easy to understand / use, easy to query and easy to slice / dice. Star schema is a database structure made up of dimensions and facts. Facts are generally the numbers (sales, quantity, etc.) that you want to slice and dice. Fact tables have these numbers and have references (foreign keys) to set of tables that provide context around those facts. E.g. if you have recorded 10,000 USD as sales that number would go in a sales fact table and could have foreign keys attached to it that refers to the sales agent responsible for sale and to time table which contains the dates between which that sale was made. These agent and time tables are called dimensions which provide context to the numbers stored in fact tables. This schema structure of fact being at center surrounded by dimensions is called Star schema. A similar structure with difference of dimension tables being normalized is called a Snowflake schema. This relational structure of facts and dimensions serves as an input for another analysis structure called Cube. Though physically Cube is a special structure supported by commercial databases like SQL Server Analysis Services, logically it’s a multidimensional structure where dimensions define the sides of cube and facts define the content. Facts are often called as Measures inside a cube. Dimensions often tend to form a hierarchy. E.g. Product may be broken into categories and categories in turn to individual items. Category and Items are often referred as Levels and their constituents as Members with their overall structure called as Hierarchy. Measures are rolled up as per dimensional hierarchy. These rolled up measures are called Aggregates. Now this may seem like an overwhelming vocabulary to deal with but don’t worry it will sink in as you start working with Cubes and others. Let’s see few other terms that we would run into while talking about data warehouses. ODS or an Operational Data Store is a frequently misused term. There would be few users in your organization that want to report on most current data and can’t afford to miss a single transaction for their report. Then there is another set of users that typically don’t care how current the data is. Mostly senior level executives who are interesting in trending, mining, forecasting, strategizing, etc. don’t care for that one specific transaction. This is where an ODS can come in handy. ODS can use the same star schema and the OLAP cubes we saw earlier. The only difference is that the data inside an ODS would be short lived, i.e. for few months and ODS would sync with OLTP system every few minutes. Data warehouse can periodically sync with ODS either daily or weekly depending on business drivers. Data marts are another frequently talked about topic in data warehousing. They are subject-specific data warehouse. Data warehouses that try to span over an enterprise are normally too big to scope, build, manage, track, etc. Hence they are often scaled down to something called Data mart that supports a specific segment of business like sales, marketing, or support. Data marts too, are often designed using star schema model discussed earlier. Industry is divided when it comes to use of data marts. Some experts prefer having data marts along with a central data warehouse. Data warehouse here acts as information staging and distribution hub with spokes being data marts connected via data feeds serving summarized data. Others eliminate the need for a centralized data warehouse citing that most users want to report on detailed data. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Best Practices, Business Intelligence, Data Warehousing, Database, Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

    - by ToStringTheory
    One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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    Hi, I'm using XNA to program a game, and have been experimenting with various ways to achieve a 'selected' effect on my sprites. The trouble I am having is that each clickable that is drawn in the spritebatch is drawn using more than a single sprite (each object can be made up of up to 6 sprites). I'd appreciate it if someone could advise me on how I could achieve adding an outline to my sprites of X pixels (so the outline width can be various numbers of whole pixels). Thanks in advance, Greg.

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    Our latest numbers... Registered Mix users (weekly growth) 61,374 (+0.6%) Active users (percent of total) Last 30 days: 4,317 (7.0%) Last 60 days: 8,638 (14.1%) Last 90 days: 12,481 (20.3%) Traffic (30-day) Visits: 11,893 Page views: 65,880 Twitter Followers: 3,169 List mentions: 146 User-generated content (30-day) New ideas: 36 New questions: 57 New comments: 394 Groups There are currently 1,402 Mix groups (requires login).

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