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  • Customize your icons in Windows 7 and Vista

    - by Matthew Guay
    Want to change out the icons on your desktop and more?  Personalizing your icons is a great way to make your PC uniquely yours,, and today we show you how to grab unique icons, and default Winnows. to be your own. Change the icon for Computer, Recycle Bin, Network, and your User folder Right-click on the desktop, and select Personalize. Now, click the “Change desktop icons” link on the left sidebar in the Personalization window. The window looks slightly different in Windows Vista, but the link is the same. Select the icon you wish to change, and click the Change Icon button.  In Windows 7, you will also notice a box to choose whether or not to allow themes to change icons, and you can uncheck it if you don’t want themes to change your icon settings. You can select one of the other included icons, or click browse to find the icon you want.  Click Ok when you are finished. Change Folder icons You can easily change the icon on most folders in Windows Vista and 7.  Simply right-click on the folder and select properties. Click the Customize tab, and then click the Change Icon button.  This will open the standard dialog to change your icon, so proceed as normal. This basically just creates a hidden desktop.ini file in the folder containing the following or similar data: [.ShellClassInfo]IconFile=%SystemRoot%\system32\SHELL32.dllIconIndex=20 You could manually create or edit the file if you choose, instead of using the dialogs. Simply create a new text file named desktop.ini with this same information, or edit the existing one.  Change the IconFile line to the location of your icon. If you are pointing to a .ico file you should change the IconIndex line to 0 instead. Note that this isn’t available for all folders, for instance you can’t use this to change the icon for the Windows folder.   In Windows 7, please note that you cannot change the icon of folder inside a library.  So if you are browsing your Documents library and would like to change an icon in that folder, right-click on it and select Open folder location.  Now you can change the icon as above. And if you would like to change a Library’s icon itself, then check out this tutorial: Change Your Windows 7 Library Icons the Easy Way Change the icon of any file type Want to make you files easier to tell apart?  Check out our tutorial on how to simply do this: Change a File Type’s Icon in Windows 7 Change the icon of any Application Shortcut To change the icon of a shortcut on your desktop, start menu, or in Explorer, simply right-click on the icon and select Properties. In the Shortcut tab, click the Change Icon button. Now choose one of the other available icons or click browse to find the icon you want. Change Icons of Running Programs in the Windows 7 taskbar If your computer is running Windows 7, you can customize the icon of any program running in the taskbar!  This only works on applications that are running but not pinned to the taskbar, so if you want to customize a pinned icon you may want to unpin it before customizing it.  But the interesting thing about this trick is that it can customize any icon anything running in the taskbar, including things like Control Panel! Right-click or click and push up to open the jumplist on the icon, and then right-click on the program’s name and select Properties.  Here we are customizing Control Panel, but you can do this on any application icon. Now, click Change Icon as usual. Select an icon you want (We switched the Control Panel icon to the Security Shield), or click Browse to find another icon.  Click Ok when finished, and then close the application window. The next time you open the program (or Control Panel in our example), you will notice your new icon on its taskbar icon. Please note that this only works on applications that are currently running and are not pinned to the taskbar.  Strangely, if the application is pinned to the taskbar, you can still click Properties and change the icon, but the change will not show up. Change the icon on any Drive on your Computer You can easily change the icon on your internal hard drives and portable drives with the free Drive Icon Changer application.  Simply download and unzip the file (link below), and then run the application as administrator by right-clicking on the icon and selecting “Run as administrator”. Now, select the drive that you want to change the icon of, and select your desired icon file. Click Save, and Drive Icon Changer will let you know that the icon has been changed successfully. You will then need to reboot your computer to complete the changes.  Simply click Yes to reboot. Now, our Drive icon is changed from this default image: to a Laptop icon we chose! You can do this to any drive in your computer, or to removable drives such as USB flash drives.  When you change these drives icons, the new icon will appear on any computer you insert the drive into.  Also, if you wish to remove the icon change, simply run the Drive Icon Changer again and remove the icon path. Download Drive Icon Changer This application actually simply creates or edits a hidden Autorun.inf file on the top of your drive.  You can edit or create the file yourself by hand if you’d like; simply include the following information in the file, and save it in the top directory of your drive: [autorun]ICON=[path of your icon] Remove Arrow from shortcut icons Many people don’t like the arrow on the shortcut icon, and there are two easy ways to do this. If you’re running the 32 bit version of Windows Vista or 7, simply use the Vista Shortcut Overlay Remover. If your computer is running the 64 bit version of Windows Vista or 7, use the Ultimate Windows Tweaker instead.  Simply select the Additional Tweaks section, and check the “Remove arrows from Shortcut Icons.” For more info and download links check out this article: Disable Shortcut Icon Arrow Overlay in Windows 7 or Vista Closing: This gives you a lot of ways to customize almost any icon on your computer, so you can make it look just like you want it to.  Stay tuned for more great desktop customization articles from How-to Geek! Similar Articles Productive Geek Tips Change Start Menu to Use Small Icons in Windows 7 or VistaResize Icons Quickly in Windows 7 or Vista ExplorerRoundup: 16 Tweaks to Windows Vista Look & FeelRestore Missing Desktop Icons in Windows 7 or VistaClean Up Past Notification Icons in Windows Vista 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 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Change DNS servers on the fly with DNS Jumper Live PDF Searches PDF Files and Ebooks Converting Mp4 to Mp3 Easily Use Quick Translator to Translate Text in 50 Languages (Firefox) Get Better Windows Search With UltraSearch Scan News With NY Times Article Skimmer

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  • Quick guide to Oracle IRM 11g: Creating your first sealed document

    - by Simon Thorpe
    Quick guide to Oracle IRM 11g indexThe previous articles in this guide have detailed how to install, configure and secure your Oracle IRM 11g service. This article walks you through the process of now creating your first context and securing a document against it. I should mention that it would be worth reviewing the following to ensure your installation is ready for that all important first document. Ensure you have correctly configured the keystore for the IRM wrapper keys. If this is not correctly configured, creating the context below will fail. Make sure the IRM server URL correctly resolves and uses the right protocol (HTTP or HTTPS) ContentsCreate the first contextInstall the Oracle IRM Desktop Seal your first document Create the first contextIn Oracle 11g there is a built in classification and rights system called the "standard rights model" which is based on 10 years of customer use cases and innovation. It is a system which enables IRM to scale massively whilst retaining the ability to balance security and usability and also separate duties by allowing contacts in the business to own classifications. The final article in this guide goes into detail on this inbuilt classification model, but for the purposes of this current article all we need to do is create at least one context to test our system out.With a new IRM server there are a set of predefined context templates and roles which again are setup in a way which reflects the most common use we've learned from our customers. We will use these out of the box configurations as they are to create the first context against which we will seal some content.First login to your Oracle IRM Management Website located at https://irm.company.com/irm_rights/. Currently the system is only configured to use the built in LDAP for users, so use the only account we have at the moment, which by default is weblogic. Once logged in switch to the Contexts tab. Click on the New Context icon () in the menu bar on the left. In the resulting dialog select the Standard context template and enter in a name for the context. Then just hit finish, the weblogic account will automatically be made the manager. You'll now see your brand new context ready for users to be assigned. Now click on the Assign Role icon () in the menu bar and in the resulting dialog search for your only user account, weblogic, and add to the list on the right. Now select a role for this user. Because we need to create a document with this user we must select contributor, as this is the only role which allows for the ability to seal. Finally hit next and then finish. We now have a context with a user that has the rights to create a document. The next step is to configure the IRM Desktop to get these rights from the server. Install the Oracle IRM Desktop Before we can seal a document we need the client software installed. Oracle IRM has a very small, lightweight client called the Oracle IRM Desktop which can be freely downloaded in 27 languages from here. Double click on the installer and click on next... Next again... And finally on install... Very easy. You may get a warning about closing Outlook, Word or another application and most of the time no reboots are required. Once it is installed you will see the IRM Desktop icon running in your tool tray, bottom right of the desktop. Seal your first document Finally the prize is within reach, creating your first sealed document. The server is running, we've got a context ready, a user assigned a role in the context but there is the simple and obvious hoop left to jump through. To seal a document we need to have the users rights cached to the local machine. For this to take place, the IRM Desktop needs to know where the Oracle IRM server is on the network so we can synchronize these rights and then be able to seal a document. The usual way for the IRM Desktop to know about the IRM server is it learns automatically when you open an existing piece of content that someone has sent you... ack. Bit of a chicken or the egg dilemma. The solution is to manually tell the IRM Desktop the location of the IRM Server and then force a synchronization of rights. Right click on the Oracle IRM Desktop icon in the system tray and select Options.... Then switch to the Servers tab in the resulting dialog. There are no servers in the list because you've never opened any content. This list is usually populated automatically but we are going to add a server manually, so click on New.... Into the dialog enter in the full URL to the IRM server. Note that this time you use the path /irm_desktop/ and not /irm_rights/. You can see an example from the image below. Click on the validate button and you'll be asked to authenticate. Enter in your weblogic username and password and also check the Remember my password check box. Click OK and the IRM Desktop will confirm a successful connection to the server. OK all the dialogs and we are ready to Synchronize this users rights to the desktop. Right click once more on the Oracle IRM Desktop icon in the system tray. Now the Synchronize menu option is available. Select this and the IRM Desktop will now talk to the IRM server, authenticate using your weblogic account and get your rights to the context we created. Because this is the first time this users has communicated with the IRM server the IRM Desktop presents a privacy policy dialog. This is a chance for the business to ask users to agree to any policy about the use of IRM before opening secured documents. In our guide we've not bothered to setup this URL so just click on the check box and hit Accept. The IRM Desktop will then talk to the server, get your rights and display a success dialog. Lets protect a documentNow we are ready to seal a piece of content. In my guide i'm going to protect a Microsoft Word document. This mean's I have to have copy of Office installed, in this guide i'm using Microsoft Office 2007. You could also seal a PDF document, you'll need to download and install Adobe Acrobat Reader. A very simple test could be to seal a GIF/JPG/PNG or piece of HTML because this is rendered using Internet Explorer. But as I say, i'm going to protect a Word document. The following example demonstrates choosing a file in Windows Explorer, there are many ways to seal a file and you can watch a few in this video.Open a copy of Windows Explorer and locate the file you wish to seal. Right click on the document and select Seal To -> Context You are now presented with the Select Context dialog. You'll now have a sealed copy of the document sat in the same location. Double click on this document and it will open, again using the credentials you've already provided. That is it, now you just need to add more users, more documents, more classifications and start exploring the different roles and experiment with different offline periods etc. You may wish to setup the server against an existing LDAP or Active Directory environment instead of using the built in WebLogic LDAP store. You can read how to use your corporate directory here. But before we finish this guide, there is one more article and arguably the most important article of all. Next I discuss the all important decision making surrounding the actually implementation of Oracle IRM inside your business. Who has rights to what? How do you map contexts to your existing business practices? It is the next article which actually ensures you deploy a successful IRM solution by looking at the business and understanding how they use your sensitive information and then configuring Oracle IRM to reflect their use.

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  • CodePlex Daily Summary for Sunday, September 30, 2012

    CodePlex Daily Summary for Sunday, September 30, 2012Popular ReleasesCAPTCHA Solver: Initial Release: This is the initial Release :) Still very much a WIP.MCEBuddy 2.x: MCEBuddy 2.2.17: Reccomended update to 2.2.16 Changelog for 2.2.17 (32bit and 64bit) 1. Fixed bugs around thread synchronization with new remote model (fixes cause the app to crash or hang) 2. Updated UPnP code base, faster and more reliable now 3. Now you can get audio/video properties for multiple files on main page. Selected multiple files and right click, all selected files properties will be shown. 4. Fix a bug, not able to enter a conversion task name in the GUIAggravation: Version 1.0: This version 1.0 release is pretty stable. You need the Silverlight 4 runtime, developer tools, and Experssion Blend 4 installed.Readable Passphrase Generator: KeePass Plugin 0.7.1: See the KeePass Plugin Step By Step Guide for instructions on how to install the plugin. Changes Built against KeePass 2.20Windows 8 Toolkit - Charts and More: Beta 1.0: The First Compiled Version of my LibraryPDF.NET: PDF.NET.Ver4.5-OpenSourceCode: PDF.NET Ver4.5 ????,????Web??????。 PDF.NET Ver4.5 Open Source Code,include a sample Web application project.D3 Loot Tracker: 1.4: Session name is displayed in the UI. Changes data directory for clickonce deployment so that sessions files are persisted between versions. Added a delete button in the sessions list window. Allow opening of the sessions local folder from the session list widow. Display the session name in the main window Ability to select which diablo process to hook up to when pressing new () function BUT only if multi-process support is selected in the generals settings tab menu. Session picker...CRM 2011 Visual Ribbon Editor: Visual Ribbon Editor 1.1 Beta: Visual Ribbon Editor 1.1 Beta What's New: Fixed scrolling issue in UnHide dialog Added support for connecting via ADFS / IFD Added support for more than one action for a button Added support for empty StringParameter for Javascript functions Fixed bug in rule CrmClientTypeRule when selecting Outlook option Extended Prefix field in New Button dialogVisual Studio Icon Patcher: Version 1.5.2: This version contains no new images from v1.5.1 Contains the following improvements: Better support for detecting the installed languages The extract & inject commands won’t run if Visual Studio is running You may now run in extract or inject mode The p/invoke code was cleaned up based on Code Analysis recommendations When a p/invoke method fails the Win32 error message is now displayed Error messages use red text Status messages use green textZXing.Net: ZXing.Net 0.9.0.0: On the way to a release 1.0 the API should be stable now with this version. sync with rev. 2393 of the java version improved api better Unity support Windows RT binaries Windows CE binaries new Windows Service demo new WPF demo WindowsCE Hotfix: Fixes an error with ISO8859-1 encoding and scannning of QR-Codes. The hotfix is only needed for the WindowsCE platform.C.B.R. : Comic Book Reader: CBR 0.7: Synthesis since 0.6 : ePUB : Complete refactoring Add a new dedicated feed viewer for opds stream PDF conversion : improved with image merge Make all backstage panel scrollable Integrate the new AvalonDock 2 library. Support multi-document. Library explorer and Table of content are now toolboxes Designer for dynamic books is now mvvm and much better New BrowserForControl Customized xps viewer to suppress toolbars and bind it to cbr commands Add quick start manual and button ...menu4web: menu4web 1.0 - free javascript menu for web sites: menu4web 1.0 has been tested with all major browsers: Firefox, Chrome, IE, Opera and Safari. Minified m4w.js library is less than 9K. Includes 21 menu examples of different styles. Can be freely distributed under The MIT License (MIT).Rawr: Rawr 5.0.0: This is the Downloadable WPF version of Rawr!For web-based version see http://elitistjerks.com/rawr.php You can find the version notes at: http://rawr.codeplex.com/wikipage?title=VersionNotes Rawr Addon (NOT UPDATED YET FOR MOP)We now have a Rawr Official Addon for in-game exporting and importing of character data hosted on Curse. The Addon does not perform calculations like Rawr, it simply shows your exported Rawr data in wow tooltips and lets you export your character to Rawr (including ba...Coevery - Free CRM: Coevery 1.0.0.26: The zh-CN issue has been solved. We also add a project management module.VidCoder: 1.4.1 Beta: Updated to HandBrake 4971. This should fix some issues with stuck PGS subtitles. Fixed build break which prevented pre-compiled XML serializers from showing up. Fixed problem where a preset would get errantly marked as modified when re-opening the encode settings window or importing a new preset.Snake!: Snake 1.0: Version 1 StablePaging SharePoint ListItems using listitems position: Paginglistitems V1.0: This is a console application which has two methods both on CSOM and SOM to display the listitems in a paged manner.SharePoint Move Discussion Threads: SharePoint Move Discussion Threads ver 0.1: ver 0.1NTCPMSG: V1.1.1.0: increase the performance. Support .net framework 4.0.BlackJumboDog: Ver5.7.2: 2012.09.23 Ver5.7.2 (1)InetTest?? (2)HTTP?????????????????100???????????New Projects2D Sprite Editor: This is a 2d sprite editor. Import your sprite sheet, trace your animations frame and export the coordinates points in a simple txt file, ready to import.caifenweb1: test project.CatchThatException: This is a small logging library We created at developerpath.com to help us log exceptions. It write it to a text file and you can easilay open that txt.FsxWs - WebServices for Microsoft FSX: WebServices for MS Flight Simulator. Get flights data as JSON, KML. !! Still in SetUp phase - be patient !!GetTPB: Some training in downloading and parsing web pages, with multithreading too.JSON-RPC Client Generator (for XBMC): The goal of this project is to provide a .Net client for the XBMC JSONRPC API. The main part is not XBMC dependent and may be used for any JSON-RPC client.matlab-silhouette-pose-wtf: Whatevermfp: this is random codeMVC Grid: MVC Grid ExampleMyWebSocketTry: sssssssssssssssssssssssssssssssssssssssNetduino Console: Netduino Console is an interface with built in messaging layers that allows you as a developer to dynamically create plugins following a provided interface to iSharePoint ASP.NET Verifier: Project will allow to verify SharePoint 2010 components using ASP.NET web applicationSharepoint Custom Upload: This is a SharePoint solution that allows an administrator to customize the upload page individually for each document library in a site.. It allows you to makeWinWeb Browser Deluxe: WinWeb Browser Deluxe es un navegador web de código abierto basado en Internet Explorer hecho en Visual Basic .NET. Descargalo ya!writethatoutput: This is the official release page for WriteThatOutPut from developerpath.com

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  • A Guided Tour of Complexity

    - by JoshReuben
    I just re-read Complexity – A Guided Tour by Melanie Mitchell , protégé of Douglas Hofstadter ( author of “Gödel, Escher, Bach”) http://www.amazon.com/Complexity-Guided-Tour-Melanie-Mitchell/dp/0199798109/ref=sr_1_1?ie=UTF8&qid=1339744329&sr=8-1 here are some notes and links:   Evolved from Cybernetics, General Systems Theory, Synergetics some interesting transdisciplinary fields to investigate: Chaos Theory - http://en.wikipedia.org/wiki/Chaos_theory – small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for chaotic systems, rendering long-term prediction impossible. System Dynamics / Cybernetics - http://en.wikipedia.org/wiki/System_Dynamics – study of how feedback changes system behavior Network Theory - http://en.wikipedia.org/wiki/Network_theory – leverage Graph Theory to analyze symmetric  / asymmetric relations between discrete objects Algebraic Topology - http://en.wikipedia.org/wiki/Algebraic_topology – leverage abstract algebra to analyze topological spaces There are limits to deterministic systems & to computation. Chaos Theory definitely applies to training an ANN (artificial neural network) – different weights will emerge depending upon the random selection of the training set. In recursive Non-Linear systems http://en.wikipedia.org/wiki/Nonlinear_system – output is not directly inferable from input. E.g. a Logistic map: Xt+1 = R Xt(1-Xt) Different types of bifurcations, attractor states and oscillations may occur – e.g. a Lorenz Attractor http://en.wikipedia.org/wiki/Lorenz_system Feigenbaum Constants http://en.wikipedia.org/wiki/Feigenbaum_constants express ratios in a bifurcation diagram for a non-linear map – the convergent limit of R (the rate of period-doubling bifurcations) is 4.6692016 Maxwell’s Demon - http://en.wikipedia.org/wiki/Maxwell%27s_demon - the Second Law of Thermodynamics has only a statistical certainty – the universe (and thus information) tends towards entropy. While any computation can theoretically be done without expending energy, with finite memory, the act of erasing memory is permanent and increases entropy. Life & thought is a counter-example to the universe’s tendency towards entropy. Leo Szilard and later Claude Shannon came up with the Information Theory of Entropy - http://en.wikipedia.org/wiki/Entropy_(information_theory) whereby Shannon entropy quantifies the expected value of a message’s information in bits in order to determine channel capacity and leverage Coding Theory (compression analysis). Ludwig Boltzmann came up with Statistical Mechanics - http://en.wikipedia.org/wiki/Statistical_mechanics – whereby our Newtonian perception of continuous reality is a probabilistic and statistical aggregate of many discrete quantum microstates. This is relevant for Quantum Information Theory http://en.wikipedia.org/wiki/Quantum_information and the Physics of Information - http://en.wikipedia.org/wiki/Physical_information. Hilbert’s Problems http://en.wikipedia.org/wiki/Hilbert's_problems pondered whether mathematics is complete, consistent, and decidable (the Decision Problem – http://en.wikipedia.org/wiki/Entscheidungsproblem – is there always an algorithm that can determine whether a statement is true).  Godel’s Incompleteness Theorems http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_theorems  proved that mathematics cannot be both complete and consistent (e.g. “This statement is not provable”). Turing through the use of Turing Machines (http://en.wikipedia.org/wiki/Turing_machine symbol processors that can prove mathematical statements) and Universal Turing Machines (http://en.wikipedia.org/wiki/Universal_Turing_machine Turing Machines that can emulate other any Turing Machine via accepting programs as well as data as input symbols) that computation is limited by demonstrating the Halting Problem http://en.wikipedia.org/wiki/Halting_problem (is is not possible to know when a program will complete – you cannot build an infinite loop detector). You may be used to thinking of 1 / 2 / 3 dimensional systems, but Fractal http://en.wikipedia.org/wiki/Fractal systems are defined by self-similarity & have non-integer Hausdorff Dimensions !!!  http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension – the fractal dimension quantifies the number of copies of a self similar object at each level of detail – eg Koch Snowflake - http://en.wikipedia.org/wiki/Koch_snowflake Definitions of complexity: size, Shannon entropy, Algorithmic Information Content (http://en.wikipedia.org/wiki/Algorithmic_information_theory - size of shortest program that can generate a description of an object) Logical depth (amount of info processed), thermodynamic depth (resources required). Complexity is statistical and fractal. John Von Neumann’s other machine was the Self-Reproducing Automaton http://en.wikipedia.org/wiki/Self-replicating_machine  . Cellular Automata http://en.wikipedia.org/wiki/Cellular_automaton are alternative form of Universal Turing machine to traditional Von Neumann machines where grid cells are locally synchronized with their neighbors according to a rule. Conway’s Game of Life http://en.wikipedia.org/wiki/Conway's_Game_of_Life demonstrates various emergent constructs such as “Glider Guns” and “Spaceships”. Cellular Automatons are not practical because logical ops require a large number of cells – wasteful & inefficient. There are no compilers or general program languages available for Cellular Automatons (as far as I am aware). Random Boolean Networks http://en.wikipedia.org/wiki/Boolean_network are extensions of cellular automata where nodes are connected at random (not to spatial neighbors) and each node has its own rule –> they demonstrate the emergence of complex  & self organized behavior. Stephen Wolfram’s (creator of Mathematica, so give him the benefit of the doubt) New Kind of Science http://en.wikipedia.org/wiki/A_New_Kind_of_Science proposes the universe may be a discrete Finite State Automata http://en.wikipedia.org/wiki/Finite-state_machine whereby reality emerges from simple rules. I am 2/3 through this book. It is feasible that the universe is quantum discrete at the plank scale and that it computes itself – Digital Physics: http://en.wikipedia.org/wiki/Digital_physics – a simulated reality? Anyway, all behavior is supposedly derived from simple algorithmic rules & falls into 4 patterns: uniform , nested / cyclical, random (Rule 30 http://en.wikipedia.org/wiki/Rule_30) & mixed (Rule 110 - http://en.wikipedia.org/wiki/Rule_110 localized structures – it is this that is interesting). interaction between colliding propagating signal inputs is then information processing. Wolfram proposes the Principle of Computational Equivalence - http://mathworld.wolfram.com/PrincipleofComputationalEquivalence.html - all processes that are not obviously simple can be viewed as computations of equivalent sophistication. Meaning in information may emerge from analogy & conceptual slippages – see the CopyCat program: http://cognitrn.psych.indiana.edu/rgoldsto/courses/concepts/copycat.pdf Scale Free Networks http://en.wikipedia.org/wiki/Scale-free_network have a distribution governed by a Power Law (http://en.wikipedia.org/wiki/Power_law - much more common than Normal Distribution). They are characterized by hubs (resilience to random deletion of nodes), heterogeneity of degree values, self similarity, & small world structure. They grow via preferential attachment http://en.wikipedia.org/wiki/Preferential_attachment – tipping points triggered by positive feedback loops. 2 theories of cascading system failures in complex systems are Self-Organized Criticality http://en.wikipedia.org/wiki/Self-organized_criticality and Highly Optimized Tolerance http://en.wikipedia.org/wiki/Highly_optimized_tolerance. Computational Mechanics http://en.wikipedia.org/wiki/Computational_mechanics – use of computational methods to study phenomena governed by the principles of mechanics. This book is a great intuition pump, but does not cover the more mathematical subject of Computational Complexity Theory – http://en.wikipedia.org/wiki/Computational_complexity_theory I am currently reading this book on this subject: http://www.amazon.com/Computational-Complexity-Christos-H-Papadimitriou/dp/0201530821/ref=pd_sim_b_1   stay tuned for that review!

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  • Keeping track of File System Utilization in Ops Center 12c

    - by S Stelting
    Enterprise Manager Ops Center 12c provides significant monitoring capabilities, combined with very flexible incident management. These capabilities even extend to monitoring the file systems associated with Solaris or Linux assets. Depending on your needs you can monitor and manage incidents, or you can fine tune alert monitoring rules to specific file systems. This article will show you how to use Ops Center 12c to Track file system utilization Adjust file system monitoring rules Disable file system rules Create custom monitoring rules If you're interested in this topic, please join us for a WebEx presentation! Date: Thursday, November 8, 2012 Time: 11:00 am, Eastern Standard Time (New York, GMT-05:00) Meeting Number: 598 796 842 Meeting Password: oracle123 To join the online meeting ------------------------------------------------------- 1. Go to https://oracleconferencing.webex.com/oracleconferencing/j.php?ED=209833597&UID=1512095432&PW=NOWQ3YjJlMmYy&RT=MiMxMQ%3D%3D 2. If requested, enter your name and email address. 3. If a password is required, enter the meeting password: oracle123 4. Click "Join". To view in other time zones or languages, please click the link: https://oracleconferencing.webex.com/oracleconferencing/j.php?ED=209833597&UID=1512095432&PW=NOWQ3YjJlMmYy&ORT=MiMxMQ%3D%3D   Monitoring File Systems for OS Assets The Libraries tab provides basic, device-level information about the storage associated with an OS instance. This tab shows you the local file system associated with the instance and any shared storage libraries mounted by Ops Center. More detailed information about file system storage is available under the Analytics tab under the sub-tab named Charts. Here, you can select and display the individual mount points of an OS, and export the utilization data if desired: In this example, the OS instance has a basic root file partition and several NFS directories. Each file system mount point can be independently chosen for display in the Ops Center chart. File Systems and Incident  Reporting Every asset managed by Ops Center has a "monitoring policy", which determines what represents a reportable issue with the asset. The policy is made up of a bunch of monitoring rules, where each rule describes An attribute to monitor The conditions which represent an issue The level or levels of severity for the issue When the conditions are met, Ops Center sends a notification and creates an incident. By default, OS instances have three monitoring rules associated with file systems: File System Reachability: Triggers an incident if a file system is not reachable NAS Library Status: Triggers an incident for a value of "WARNING" or "DEGRADED" for a NAS-based file system File System Used Space Percentage: Triggers an incident when file system utilization grows beyond defined thresholds You can view these rules in the Monitoring tab for an OS: Of course, the default monitoring rules is that they apply to every file system associated with an OS instance. As a result, any issue with NAS accessibility or disk utilization will trigger an incident. This can cause incidents for file systems to be reported multiple times if the same shared storage is used by many assets, as shown in this screen shot: Depending on the level of control you'd like, there are a number of ways to fine tune incident reporting. Note that any changes to an asset's monitoring policy will detach it from the default, creating a new monitoring policy for the asset. If you'd like, you can extract a monitoring policy from an asset, which allows you to save it and apply the customized monitoring profile to other OS assets. Solution #1: Modify the Reporting Thresholds In some cases, you may want to modify the basic conditions for incident reporting in your file system. The changes you make to a default monitoring rule will apply to all of the file systems associated with your operating system. Selecting the File Systems Used Space Percentage entry and clicking the "Edit Alert Monitoring Rule Parameters" button opens a pop-up dialog which allows you to modify the rule. The first screen lets you decide when you will check for file system usage, and how long you will wait before opening an incident in Ops Center. By default, Ops Center monitors continuously and reports disk utilization issues which exist for more than 15 minutes. The second screen lets you define actual threshold values. By default, Ops Center opens a Warning level incident is utilization rises above 80%, and a Critical level incident for utilization above 95% Solution #2: Disable Incident Reporting for File System If you'd rather not report file system incidents, you can disable the monitoring rules altogether. In this case, you can select the monitoring rules and click the "Disable Alert Monitoring Rule(s)" button to open the pop-up confirmation dialog. Like the first solution, this option affects all file system monitoring. It allows you to completely disable incident reporting for NAS library status or file system space consumption. Solution #3: Create New Monitoring Rules for Specific File Systems If you'd like to have the greatest flexibility when monitoring file systems, you can create entirely new rules. Clicking the "Add Alert Monitoring Rule" (the icon with the green plus sign) opens a wizard which allows you to define a new rule.  This rule will be based on a threshold, and will be used to monitor operating system assets. We'd like to add a rule to track disk utilization for a specific file system - the /nfs-guest directory. To do this, we specify the following attribute FileSystemUsages.name=/nfs-guest.usedSpacePercentage The value of name in the attribute allows us to define a specific NFS shared directory or file system... in the case of this OS, we could have chosen any of the values shown in the File Systems Utilization chart at the beginning of this article. usedSpacePercentage lets us define a threshold based on the percentage of total disk space used. There are a number of other values that we could use for threshold-based monitoring of FileSystemUsages, including freeSpace freeSpacePercentage totalSpace usedSpace usedSpacePercentage The final sections of the screen allow us to determine when to monitor for disk usage, and how long to wait after utilization reaches a threshold before creating an incident. The next screen lets us define the threshold values and severity levels for the monitoring rule: If historical data is available, Ops Center will display it in the screen. Clicking the Apply button will create the new monitoring rule and active it in your monitoring policy. If you combine this with one of the previous solutions, you can precisely define which file systems will generate incidents and notifications. For example, this monitoring policy has the default "File System Used Space Percentage" rule disabled, but the new rule reports ONLY on utilization for the /nfs-guest directory. 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  • Is Berkeley DB a NoSQL solution?

    - by Gregory Burd
    Berkeley DB is a library. To use it to store data you must link the library into your application. You can use most programming languages to access the API, the calls across these APIs generally mimic the Berkeley DB C-API which makes perfect sense because Berkeley DB is written in C. The inspiration for Berkeley DB was the DBM library, a part of the earliest versions of UNIX written by AT&T's Ken Thompson in 1979. DBM was a simple key/value hashtable-based storage library. In the early 1990s as BSD UNIX was transitioning from version 4.3 to 4.4 and retrofitting commercial code owned by AT&T with unencumbered code, it was the future founders of Sleepycat Software who wrote libdb (aka Berkeley DB) as the replacement for DBM. The problem it addressed was fast, reliable local key/value storage. At that time databases almost always lived on a single node, even the most sophisticated databases only had simple fail-over two node solutions. If you had a lot of data to store you would choose between the few commercial RDBMS solutions or to write your own custom solution. Berkeley DB took the headache out of the custom approach. These basic market forces inspired other DBM implementations. There was the "New DBM" (ndbm) and the "GNU DBM" (GDBM) and a few others, but the theme was the same. Even today TokyoCabinet calls itself "a modern implementation of DBM" mimicking, and improving on, something first created over thirty years ago. In the mid-1990s, DBM was the name for what you needed if you were looking for fast, reliable local storage. Fast forward to today. What's changed? Systems are connected over fast, very reliable networks. Disks are cheep, fast, and capable of storing huge amounts of data. CPUs continued to follow Moore's Law, processing power that filled a room in 1990 now fits in your pocket. PCs, servers, and other computers proliferated both in business and the personal markets. In addition to the new hardware entire markets, social systems, and new modes of interpersonal communication moved onto the web and started evolving rapidly. These changes cause a massive explosion of data and a need to analyze and understand that data. Taken together this resulted in an entirely different landscape for database storage, new solutions were needed. A number of novel solutions stepped up and eventually a category called NoSQL emerged. The new market forces inspired the CAP theorem and the heated debate of BASE vs. ACID. But in essence this was simply the market looking at what to trade off to meet these new demands. These new database systems shared many qualities in common. There were designed to address massive amounts of data, millions of requests per second, and scale out across multiple systems. The first large-scale and successful solution was Dynamo, Amazon's distributed key/value database. Dynamo essentially took the next logical step and added a twist. Dynamo was to be the database of record, it would be distributed, data would be partitioned across many nodes, and it would tolerate failure by avoiding single points of failure. Amazon did this because they recognized that the majority of the dynamic content they provided to customers visiting their web store front didn't require the services of an RDBMS. The queries were simple, key/value look-ups or simple range queries with only a few queries that required more complex joins. They set about to use relational technology only in places where it was the best solution for the task, places like accounting and order fulfillment, but not in the myriad of other situations. The success of Dynamo, and it's design, inspired the next generation of Non-SQL, distributed database solutions including Cassandra, Riak and Voldemort. The problem their designers set out to solve was, "reliability at massive scale" so the first focal point was distributed database algorithms. Underneath Dynamo there is a local transactional database; either Berkeley DB, Berkeley DB Java Edition, MySQL or an in-memory key/value data structure. Dynamo was an evolution of local key/value storage onto networks. Cassandra, Riak, and Voldemort all faced similar design decisions and one, Voldemort, choose Berkeley DB Java Edition for it's node-local storage. Riak at first was entirely in-memory, but has recently added write-once, append-only log-based on-disk storage similar type of storage as Berkeley DB except that it is based on a hash table which must reside entirely in-memory rather than a btree which can live in-memory or on disk. Berkeley DB evolved too, we added high availability (HA) and a replication manager that makes it easy to setup replica groups. Berkeley DB's replication doesn't partitioned the data, every node keeps an entire copy of the database. For consistency, there is a single node where writes are committed first - a master - then those changes are delivered to the replica nodes as log records. Applications can choose to wait until all nodes are consistent, or fire and forget allowing Berkeley DB to eventually become consistent. Berkeley DB's HA scales-out quite well for read-intensive applications and also effectively eliminates the central point of failure by allowing replica nodes to be elected (using a PAXOS algorithm) to mastership if the master should fail. This implementation covers a wide variety of use cases. MemcacheDB is a server that implements the Memcache network protocol but uses Berkeley DB for storage and HA to replicate the cache state across all the nodes in the cache group. Google Accounts, the user authentication layer for all Google properties, was until recently running Berkeley DB HA. That scaled to a globally distributed system. That said, most NoSQL solutions try to partition (shard) data across nodes in the replication group and some allow writes as well as reads at any node, Berkeley DB HA does not. So, is Berkeley DB a "NoSQL" solution? Not really, but it certainly is a component of many of the existing NoSQL solutions out there. Forgetting all the noise about how NoSQL solutions are complex distributed databases when you boil them down to a single node you still have to store the data to some form of stable local storage. DBMs solved that problem a long time ago. NoSQL has more to do with the layers on top of the DBM; the distributed, sometimes-consistent, partitioned, scale-out storage that manage key/value or document sets and generally have some form of simple HTTP/REST-style network API. Does Berkeley DB do that? Not really. Is Berkeley DB a "NoSQL" solution today? Nope, but it's the most robust solution on which to build such a system. Re-inventing the node-local data storage isn't easy. A lot of people are starting to come to appreciate the sophisticated features found in Berkeley DB, even mimic them in some cases. Could Berkeley DB grow into a NoSQL solution? Absolutely. Our key/value API could be extended over the net using any of a number of existing network protocols such as memcache or HTTP/REST. We could adapt our node-local data partitioning out over replicated nodes. We even have a nice query language and cost-based query optimizer in our BDB XML product that we could reuse were we to build out a document-based NoSQL-style product. XML and JSON are not so different that we couldn't adapt one to work with the other interchangeably. Without too much effort we could add what's missing, we could jump into this No SQL market withing a single product development cycle. Why isn't Berkeley DB already a NoSQL solution? Why aren't we working on it? Why indeed...

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  • Convert DVD to MP4 / H.264 with HD Decrypter and Handbrake

    - by DigitalGeekery
    Are you looking for a way to convert your DVD collection to high quality MP4 files? Today we are going to take a look at using DVDFab HD Decrypter along with Handbrake to convert DVDs to MP4 using the H.264 codec.  Process Overview Handbrake is a great file conversion application, but it unfortunately can’t handle DVD copy protection. For that we will use DVDFab’s HD Decrypter. HD Decrypter is the always free portion of the DVDFab application. What HD Decrypter will do, is remove the copy protection from your DVD, and copy the Video-TS and Audio-TS folders to your hard drive. Once the copy protection is gone, we will use Handbrake to convert the files to MP4 format with H.264 compression. Note: You’ll get full access to all the options in DVDFab  during the 30 trial period. However, the HD Decrypter is free and will continue to work. Ripping the DVD Install both Handbrake and DVDFab HD Decrypter. (Download links below) Once the applications are installed, place your DVD into your DVD drive and open DVDFab. On the welcome screen, click “Start DVDFab.”   You’ll be prompted to choose your region. Click “OK.” The disc is analyzed and opened… You’ll be brought to the main interface. Make sure you have the Full Disc option selected at the left panel and “Copy DVD-Video (VIDEO_TS folder) is selected. Click “Start.” Don’t be confused by the “DVD to DVD” option pop up. We won’t actually be burning to DVD. The HD Decrypter portion of the DVDFab suite is part of the DVD to DVD option. Click “OK.” The DVD will be ripped to your hard drive. When the copy process is complete, you’ll be prompted to insert media to start the write process. We aren’t going to be burning to disc, so just click Cancel then close out of DVDFab.   Converting to MP4 Now we are ready to convert Open Handbrake and click on the “Source” button at the top left. Select DVD / VIDEO_TS folder from the drop down list. Now we need to browse for the location where DVDFab HD Decrypter copied your movie. By default, that location will be the \DVDFab\Temp\FullDisc directory in your Documents folder. For example, in Windows 7, it would be: C:\Users\%username%\Documents\DVDFab\Temp\FullDisc\[Name of Your DVD] Select the folder, and click “OK.” You may be prompted to set a default path in Handbrake. This is an optional step. Click “OK.” If you’d like to set a default destination folder, Go to Tools on the top menu, select Options. On the General tab, click “Browse” to select a destination output folder. Click “Close” when Finished.   Next, click the dropdown list next to “Title.” Select the title that matches the length of the movie. It’s possible you may have see more than one title with a similar length. If so, consult the DVD information, or a site like IMDB.com, to find the proper movie title length. Select your container under Output Settings. This will be your final output file extension. We will be using MP4 for this example. You also have the option of MKV.   If you didn’t set up a default destination folder, you’ll need to select one by clicking the “Browse” button. You can manually customize the output file name and change the output file extension to .mp4 (Unless you prefer the iPod friendly .m4v extension). Settings There are a variety of custom settings that can be changed either through the tabs listed under Output Settings, or by selecting one of the Presets to the right. If converting exclusively for any of the devices listed in the preset list, simply click on that device and the settings will be automatically applied in the Output Settings tabs. For more Universal (non-Apple) devices or output, select the Normal profile.   For the most part, the presets will suit quite nicely. However, you can further customize settings if you’d like. The Picture tab allows you to tweak the size or cropping region. You must change Anamorphic to Loose or Custom to change the size.   The Video tab allows you to choose your codec. H.264 is the default. You also have the option to choose a target (output) size. The Constant Quality is recommended to be set between 59% – 63%. Anything over 70% will likely result in an output file larger than the input without any improved quality. On the Subtitles tab, you can select an available subtitle from the dropdown list and click “Add” to add it to the output file. When you’ve finished any customizations you are ready to begin the conversion process. Click “Start.” A Command window will open and you can follow the process. You’ll probably want to find something to do in the meantime as the process could take a couple of hours. When the process completes, you’re ready to watch your video.   Although it’s a time consuming process that involves a couple steps, this method will give you high quality H.264 video files. If you want to rip and burn your DVD’s to ISO check out our article on how to rip and convert DVD’s to an ISO image. Links Download DVDFab HD Decrypter (Part of the DVDFab suite) Download Handbrake Similar Articles Productive Geek Tips Enjoy Quick & Easy Unit Conversion with Convert for WindowsConvert Older Excel Documents to Excel 2007 FormatCalculate with Qalculate on LinuxHow To Convert Video Files to MP3 with VLCConvert a Row to a Column in Excel the Easy Way 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 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Use Quick Translator to Translate Text in 50 Languages (Firefox) Get Better Windows Search With UltraSearch Scan News With NY Times Article Skimmer SpeedyFox Claims to Speed up your Firefox Beware Hover Kitties Test Drive Mobile Phones Online With TryPhone

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  • Silverlight for Windows Embedded Tutorial (step 5 and a bit of Windows Phone 7)

    - by Valter Minute
    If you haven’t spent the last week in the middle of the Sahara desert or traveling on a sled in the north pole area you should have heard something about the launch of Windows Phone 7 Series (or Windows Phone Series 7, or Windows Series Phone 7 or something like that). Even if you are in the middle of the desert or somewhere around the north pole you may have been reached by the news, since it seems that WP7S (using the full name will kill my available bandwidth!) is generating a lot of buzz in the development and IT communities. One of the most important aspects of this new platform is that it will be programmed using a new set of tools and frameworks, completely different from the ones used on older releases of Windows Mobile (or SmartPhone, or PocketPC or whatever…). WP7S applications can be developed using Silverlight or XNA. If you want to learn something more about WP7S development you can download the preview of Charles Petzold’s book about it: http://www.charlespetzold.com/phone/index.html Charles Petzold is also the author of “Programming Windows”, the first book I ever read about programming on Windows (it was Windows 3.0 at that time!). The fact that even I was able to learn how to develop Windows application is a proof of the quality of Petzold’s work. This book is up to his standards and the 150pages preview is already rich in technical contents without being boring or complicated to understand. I may be able to become a Windows Phone developer thanks to mr. Petzold. Mr. Petzold uses some nice samples to introduce the basic concepts of Silverlight development on WP7S. On this new platform you’ll use managed code to develop your application, so those samples can’t be ported on Windows CE R3 as they are, but I would like to take one of the first samples (called “SilverlightTapHello1”) and adapt it to Silverlight for Windows Embedded to show that even plain old native code can be used to develop “cool” user interfaces! The sample shows the standard WP7S title header and a textbox with an hello world message inside it. When the user touches the textbox, it will change its color. When the user touches the background (Grid) behind it, its default color (plain old White) will be restored. Let’s see how we can implement the same features on our embedded device! I took the XAML code of the sample (you can download the book samples here: http://download.microsoft.com/download/1/D/B/1DB49641-3956-41F1-BAFA-A021673C709E/CodeSamples_DRAFTPreview_ProgrammingWindowsPhone7Series.zip) and changed it a little bit to remove references to WP7S or managed runtime. If you compare the resulting files you will see that I was able to keep all the resources inside the App.xaml files and the structure of  MainPage.XAML almost intact. This is the Silverlight for Windows Embedded version of MainPage.XAML: <UserControl x:Class="SilverlightTapHello1.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:phoneNavigation="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Navigation" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="800" FontFamily="{StaticResource PhoneFontFamilyNormal}" FontSize="{StaticResource PhoneFontSizeNormal}" Foreground="{StaticResource PhoneForegroundBrush}" Width="640" Height="480">   <Grid x:Name="LayoutRoot" Background="{StaticResource PhoneBackgroundBrush}"> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> </Grid.RowDefinitions>   <!--TitleGrid is the name of the application and page title--> <Grid x:Name="TitleGrid" Grid.Row="0"> <TextBlock Text="SILVERLIGHT TAP HELLO #1" x:Name="textBlockPageTitle" Style="{StaticResource PhoneTextPageTitle1Style}"/> <TextBlock Text="main page" x:Name="textBlockListTitle" Style="{StaticResource PhoneTextPageTitle2Style}"/> </Grid>   <!--ContentGrid is empty. Place new content here--> <Grid x:Name="ContentGrid" Grid.Row="1" MouseLeftButtonDown="ContentGrid_MouseButtonDown" Background="{StaticResource PhoneBackgroundBrush}"> <TextBlock x:Name="TextBlock" Text="Hello, Silverlight for Windows Embedded!" HorizontalAlignment="Center" VerticalAlignment="Center" /> </Grid> </Grid> </UserControl> If you compare it to the WP7S sample (not reported here to avoid any copyright issue) you’ll notice that I had to replace the original phoneNavigation:PhoneApplicationPage with UserControl as the root node. This make sense because there is not support for phone applications on CE 6. I also had to specify width and height of my main page (on the WP7S device this will be adjusted by the OS) and I had to replace the multi-touch event handler with the MouseLeftButtonDown event (no multitouch support for Windows CE R3, still). I also changed the hello message, of course. I used XAML2CPP to generate the boring part of our application and then added the initialization code to WinMain: int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { if (!XamlRuntimeInitialize()) return -1;   HRESULT retcode;   IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return -1; XRXamlSource dictsrc;   dictsrc.SetResource(hInstance,TEXT("XAML"),IDR_XAML_App);   if (FAILED(retcode=app->LoadResourceDictionary(&dictsrc,NULL))) return -1;   MainPage page;   if (FAILED(page.Init(hInstance,app))) return -1;   UINT exitcode;   if (FAILED(page.GetVisualHost()->StartDialog(&exitcode))) return -1;   return exitcode; }   You may have noticed that there is something different from the previous samples. I added the code to load a resource dictionary. Resources are an important feature of XAML that allows you to define some values that could be replaced inside any XAML file loaded by the runtime. You can use resources to define custom styles for your fonts, backgrounds, controls etc. and to support internationalization, by providing different strings for different languages. The rest of our WinMain isn’t that different. It creates an instances of our MainPage object and displays it. The MainPage class implements an event handler for the MouseLeftButtonDown event of the ContentGrid: class MainPage : public TMainPage<MainPage> { public:   HRESULT ContentGrid_MouseButtonDown(IXRDependencyObject* source,XRMouseButtonEventArgs* args) { HRESULT retcode; IXRSolidColorBrushPtr brush; IXRApplicationPtr app;   if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode;   if (FAILED(retcode=app->CreateObject(IID_IXRSolidColorBrush,&brush))) return retcode;   COLORREF color=RGBA(0xff,0xff,0xff,0xff);   if (args->pOriginalSource==TextBlock) color=RGBA(rand()&0xFF,rand()&0xFF,rand()&0xFF,0xFF);   if (FAILED(retcode=brush->SetColor(color))) return retcode;   if (FAILED(retcode=TextBlock->SetForeground(brush))) return retcode; return S_OK; } }; As you can see this event is generated when a used clicks inside the grid or inside one of the objects it contains. Since our TextBlock is inside the grid, we don’t need to provide an event handler for its MouseLeftButtonDown event. We can just use the pOriginalSource member of the event arguments to check if the event was generated inside the textblock. If the event was generated inside the grid we create a white brush,if it’s inside the textblock we create some randomly colored brush. Notice that we need to use the RGBA macro to create colors, specifying also a transparency value for them. If we use the RGB macro the resulting color will have its Alpha channel set to zero and will be transparent. Using the SetForeground method we can change the color of our control. You can compare this to the managed code that you can find at page 40-41 of Petzold’s preview book and you’ll see that the native version isn’t much more complex than the managed one. As usual you can download the full code of the sample here: http://cid-9b7b0aefe3514dc5.skydrive.live.com/self.aspx/.Public/SilverlightTapHello1.zip And remember to pre-order Charles Petzold’s “Programming Windows Phone 7 series”, I bet it will be a best-seller! Technorati Tags: Silverlight for Windows Embedded,Windows CE

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  • CodePlex Daily Summary for Sunday, May 09, 2010

    CodePlex Daily Summary for Sunday, May 09, 2010New ProjectsArtificial Spy: ASPX, C#, XML, This is big project for creation application for: People Search. People connection. Background check. Crime Prevention. Socia...Chef Framework: CHEF: CSS, HTML, Events, & Functions. Is a collection of libraries to help build concerns separated websites.Crabit Full File Manger: File manager SystemEPiMVC - EPiServer CMS with ASP.NET MVC: A framework for using EPiServer CMS with ASP.NET MVC.Fimyid IX: all My projects In ONE!Hosting Folder Sizes: When you run a hosting environment with the ability to upload files, and you're charging per gigabyte per month, you need quick statistics about di...Let's Up: A tool that breaks you every 50 minutes to protect your health.MediaXenter: MediaXenterMSClub BY: Microsoft community web-site projectOrbisArca: Windows Mobile gameSpatial Gateway: A common and standardized way of accessing spatial data stored in different datastores. This also includes functionality for replication across dif...Squiggle - A Free open source Lan Messenger: Squiggle is a free lan messenger that does not require a server. Just download and run it and you're ready to talk to everyone on your lan. Squi...Video Downloader: Video Downloader makes it easier for developers to generate download links for videos from You-Tube. You'll no longer have to search through source...ViewModelSupport: This is not an MVVM framework. It is just the base class I use to reduce the friction when writing ViewModels. Making it public to share my ideas.WPF CCTV Surveillance Control with IP Cameras.: Integracion de Video IP en WPF. IP Camera. WPF dinamic Control and Events in Video System. Surveillance system. CCTV system. .NetNew Releases.NET Extensions - Extension Methods Library: Release 2010.07: Added some extension methods for ICollection<T> and IList<T> for demonstrating the differences between both interfaces: - ICollection<T>.AddRangeU...bitly.net: bitly.dll: This is a .net DLL that works with the on-line URL shortening service bit.ly Compiled using .net 4.0 but the source code should run with version 2 ...Crabit Full File Manger: Crabit V1.0: Firts file manager system previewCSharp Intellisense: V1.9: this is a major release that was focus on bug fix, tooltip support and styling.Fimyid IX: fimyid ix 1.0: New Liscence!Gherkin editor: Beta: Added support for i18n (all languages supported by Gherkin/Cucumber are suported). Removed auto-completion of statements like As a user and followi...Grunty OS: GruntyOSAlphaSC: Grunty os sourceHKGolden Express: HKGoldenExpress (Build 201005081830): New features: Users can post new message or reply to a message. Special thanks for help from members 劉佳偉 (ID: 179892) and Maize. (ID: 142974). Bu...iLove SharePoint: Lookup Field with Picker 2010: Just forget the fuc**** dropdowns! Requirements: SharePoint Foundation 2010 Features * Single- and multi-Selection Mode * Search in pick...LazyNet: LazyNet Beta 2: Refresh Network Bug fixed.LazyNet: LazyNEt_Beta3: Beta 3 Release, Better Network RefreshingLazyNet: LazyNetBeta3_SRC: Refresh NetworkLet's Up: 1.0 (Build 100509): This is the first versionLive Distributed Objects: Windows Installer r48444 (2010-05-08): current development snapshotMDownloader: MDownloader-0.15.12.58576: Fixed presenting Hotfile's captcha. Fixed FilesTube searching. Fixed determining Rapidshare postpone period. Fixed minor bugs.NSIS Autorun: NSIS Autorun 0.1.7: This release includes source code, executable binaries and example materials.SharpDevelop: SharpDevelop 3.2: Release notes: http://community.sharpdevelop.net/forums/t/11165.aspxSilverlight SDK for Bing: Silverlight SDK for Bing 1.4: Build for Visual Studio 2010 and Silverlight 4 Issues Addressed10337 10342 10367 10804 10805 10806 10807 DownloadsSilverlight SDK For B...sqwarea: Sqwarea 0.0.252.0 (alpha): This release corrects a critical bug in Persistence.GameProvider.GetNextKingId. We strongly recommend you to upgrade to this version.Stratosphere: Stratosphere 1.0.5.1: Added many features to Amazon Web Services Shell (AwsSh) Improved scalable table reader for SimpleDB multi-valued attributes Added more functio...TechEdOneNoter: TechEdOneNoter verison 2010.5.9.2010: TechEdOneNoter is a utility to create OneNote Pages based on sessions selected in the TechEd North America 2010 Session Builder. This is the first...Video Downloader: Version 1.0: Version 1.0 See Home Page for usage and more information. Please remember changes at You-Tube can prevent this software from working.Visual Studio - Lua Language Support: May 8th Update: Release NotesThis release adds collapsible functions and tables. What's new:Collapsible functions and tables Using latest version of Irony Maj...WPF CCTV Surveillance Control with IP Cameras.: Hungry Foxx CCTV Preview: Este release, corresponde a una muestra del programa completo. La idea es poder contar con una solucion para los integradores de sistemas CCTV o d...XsltDb - DotNetNuke XSLT module: 01.01.08: Bugs fixed: 17204 17203 Many new features, but undocumented yet. I'm going to update docs in a week or two, but...Most Popular ProjectsWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesASP.NETPHPExcelMost Active Projectspatterns & practices – Enterprise LibraryRawrThe Information Literacy Education Learning Environment (ILE)AJAX Control FrameworkCaliburn: An Application Framework for WPF and SilverlightMirror Testing SystemjQuery Library for SharePoint Web Servicespatterns & practices - UnityBlogEngine.NETTweetSharp

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  • CodePlex Daily Summary for Saturday, March 27, 2010

    CodePlex Daily Summary for Saturday, March 27, 2010New ProjectsAlter gear SQL index Management: SQL Index management displays a list of indexes available for the chosen database and allows you to select an individual / group of indexes to be r...ASP League Ladder System: An ASP ladder / league system for online gaming league or real life leagues also.Augmented Reality Strategy Simulator: Augmented Reality Strategy Simulator is a software suite to promote computer aided strategy planning. Sports team can visualize their strategy usin...Boo syntax highlighting for Visual Studio 2010: Simple syntax hightlighting VSX add-in for Boo language in Visual Studio 2010.easySan: easySan zur einfachen Mitgliedsverwaltung im BRKFsUnit: FsUnit makes unit-testing with F# more enjoyable. It adds a special syntax to your favorite .NET testing framework.Laughing Dog XNA Framework: Laughing Dog is a simple to use, component based 2D framework for XNA game development. At present it is very early in development and as such is f...miniTodo: WPFでMVVMの練習にてきとうに作ったTODOアプリ 実用は無理です。My Common Library on .NET with CSharp: My Common Library on .NET with CSharp, it conclude database assecc, encrypt string, data caching, StringUtility, thank you for your view.Native code wrapping using c# : fsutil sparse commands: Ever thought about creating HUGE FILES for future use but felt bad for the wasted memory? Well, SPARSE FILES are the ANSWER! This FSUTIL SPARSE CO...Open SOA Platform: A centralized system for administering applications throught a SOA Enterprise Service Bus: Runtime environment (PROD, DEV, ...) , application and s...P-DBMS: Network and Database ProjectPraiseSight: PraiseSight is supposed to become a practical tool for churches to catalog an present their songs, lyrics and presentations on a beamer. The soluti...Pretty Good Frontend: Pretty Good Frontend is a sample frontend for ConfigMgr (SCCM) 2007 and MDT 2010 Zero Touch. S3Appender (Appender for Log4Net that Uses Amazon S3 For Storing Log Files): The S3Appender is a log4net appender that stores log events in either a MemoryStream or FileStream and sends them to S3 based on time intervals and...sEmit: sEmit (sms emitter) is an application written in C# which was built to send text messages. The project was founded in May 2009 by cansik. It works ...Silverlight RIA Tools: A tool set that generates a full RIA Solutions in Silverlightthommo cannon: Cannon for shooting down ThommosTianjin Polytechnic University Online Judge: Online Judge System Built on Microsoft technologies. Vision & Scope: A distributed OJ Solution on Windows and Cloud. Technologies used or planed...Tinare: Tinare is an byte encryption and decryption alogrithm. The input key is a string password.TinyPlug: Small Plugin Manager, written in C# Allows a project to define supported interfaces, and at runtime add plugins which support (inherit) these in...Utility niconv helps to convert text from one encoding to another: .NET implementation of GUN iconv console converter utility. The niconv program converts text from one encoding to another encoding. In the future r...WareFeed - Software Business Analytics: WareFeed is a simple but effective Software Business Analytics tool written in PHP and compatible others languages such as .NET, Java or Python. It...Y36API1: Semestralni projekt na Y36APINew ReleasesAlter gear SQL index Management: Setup 1.0.0: setup for first alpha releaseASP League Ladder System: ASPLeagueRelease_0_4_1: Release v 0.41Augmented Reality Strategy Simulator: Augmented Reality Strategy Simulator: Version 1.0 InstallerAutoAudit: AutoAudit 1.10e: Version 1.10e will be the final iteration of version 1 development. Version 2 will begin adding switches and options. Pleae email your suggestio...Boo syntax highlighting for Visual Studio 2010: Boo syntax VS 2010 - alpha: First release TODO: Multiline comments!Chargify.NET: Chargify.NET 0.6: Updated library, using Metered Components and updated Product information.Composer: V1.0.326.1000 Alpha: Initial Alpha release. Should be stable, with minor issues.CoNatural Components: CoNatural Components 1.6: Code fixes: Created helper classes to generate source code for type mapper/materializer. Fixed issue in optimized type materializer when loading ...CRM External View: 1.2: New Features in v1.2 release Password protected views. No more using Web Data Access role from v1. Filtering capabilities Caching for performan...Designit Video Embed Package: Release 1.1.0 beta1: You can now either have the video embeded directly in the template or have a preview in template that opens the video in a lightbox window.FsUnit: FsUnit 0.9.0 for NUnit: This release is for F# 2.0 and NUnit 2.5+.Laughing Dog XNA Framework: Laughing Dog 0.0.1: Laughing Dog - Alpla - v 0.0.1 First released version of the Laughing Dog framework.LiveUpload to Facebook: LiveUpload to Facebook 3.2: Version 3.2Become a fan on Facebook! Features Quickly and easily upload your photos and videos to Facebook, including any people tags added in Win...MapWindow6: MapWindow 6.0 msi March 26: This version adds the Join feature for creating a new "featureset" with attributes that are joined with attributes from a Excel data label named 'D...Mobile Broadband Logging Monitor: Mobile Broadband Logging Monitor 1.2.2: This edition supports: Newer and older editions of Birdstep Technology's EasyConnect HUAWEI Mobile Partner MWConn User defined location for s...Multiplayer Quiz: Release 1_6_351_0: A beta release of the next version. Please leave any errors in discussions or comments.Native code wrapping using c# : fsutil sparse commands: Fsutil sparse file native code - c sharp wrapper: Project Description A C# code wrapping a native code-Sparse files1 The code is about SPARSE files- the abillity to create huge files (for future us...Nice Libraries: 1.30 build 50325.01: Release 1.30 build 50325.01Pretty Good Frontend: Pretty Good Frontend binaries v1.0: This is the first public release of the Pretty Good Frontend binariesPylor: Pylor 0.1 alpha: This is the very first published version. I hope I can put a sample project soon.Quick Performance Monitor: Version 1.1 refresh: There was a typo or two in the sample batch file. Corrected now.Rapidshare Episode Downloader: RED v0.8.3: 0.8.1 introduced the ability to advance to the next episode. In 0.8.2 a bug was found that if episode number is less then 10, then the preceding 0...RapidWebDev - .NET Enterprise Software Development Infrastructure: RapidWebDev 1.52: RapidWebDev is an infrastructure helps to develop enterprise software solutions in Microsoft .NET easily and productively. This is the release vers...thommo cannon: game: gamethommo cannon: setup: setupthommo cannon: test: testTinare: Tinare DLL: Tinare DLL is a dynamic-link library written in C# which provides the functions to encrypt and decrypt a byte stream with tinare.WeatherBar: WeatherBar 2.1 [No Installation]: Minor changes to release 2.0 (http://weatherbar.codeplex.com/releases/view/42490). Fixed the bug that caused an exception to be thrown if the user...Most Popular ProjectsMetaSharpRawrWBFS ManagerASP.NET Ajax LibrarySilverlight ToolkitMicrosoft SQL Server Product Samples: DatabaseAJAX Control ToolkitLiveUpload to FacebookWindows Presentation Foundation (WPF)ASP.NETMost Active ProjectsRawrjQuery Library for SharePoint Web ServicesBlogEngine.NETMicrosoft Biology FoundationFarseer Physics Enginepatterns & practices: Composite WPF and SilverlightLINQ to TwitterTable2ClassFluent Ribbon Control SuiteNB_Store - Free DotNetNuke Ecommerce Catalog Module

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  • The APEX of Business Value...or...the Business Value of APEX? Oracle Cloud Takes Oracle APEX to New Heights!

    - by Gene Eun
    The attraction of Oracle Application Express (APEX) has increased tremendously with the recent launch of the Oracle Cloud. APEX already supported departmental development and deployment of business applications with minimal involvement from the IT department. Positioned as the ideal replacement for MS Access, APEX probably has managed better to capture the eye of developers and was used for enterprise application development at least as much as for the kind of tactical applications that Oracle strategically positioned it for. With APEX as PaaS from the Oracle Cloud, a leap is made to a much higher level of business value. Now the IT department is not even needed to make infrastructure available with a database running  on it. All the business needs is a credit card. And the business application that is developed, managed and used from the cloud through a standard browser can now just as easily be accessed by users from around the world as by users from the business department itself. As a bonus – the development of the APEX application is also done in the cloud – with no special demands on the location or the enterprise access privileges of the developers. To sum it up: APEX from Oracle Cloud Database Service get the development environment up and running in minutes no involvement from the internal IT department required (not for infrastructure, platform, or development) superior availability and scalability is offered by Oracle users from anywhere in the world can be invited to access the application developers from anywhere in the world can participate in creating and maintaining the application In addition: because the Oracle Cloud platform is the same as the on-premise platform, you can still decide to move the APEX application between the cloud and the local environment – and back again. The REST-ful services that are available through APEX allow programmatic interaction with the database under the APEX application. That means that this database can be synchronized with on premise databases or data stores in (other) clouds. Through the Oracle Cloud Messaging Service, the APEX application can easily enter into asynchronous conversations with other APEX applications, Fusion Middleware applications (ADF, SOA, BPM) and any other type of REST-enabled application. In my opinion, now, for the first time perhaps, APEX offers the attraction to the business that has been suggested before: because of the cloud, all the business needs is  a credit card (a budget of $175 per month), an internet-connection and a browser. Not like before, with a PC hidden under a desk or a database running somewhere in the data center. No matter how unattended: equipment is needed, power is consumed, the database needs to be kept running and if Oracle Database XE does not suffice, software licenses are required as well. And this set up always has a security challenge associated with it. The cloud fee for the Oracle Cloud Database Service includes infrastructure, power, licenses, availability, platform upgrades, a collection of reusable application components and the development and runtime environments containing the APEX platform. Of course this not only means that business departments can move quickly without having to convince their IT colleagues to move along – it also means that small organizations that do not even have IT colleagues can do the same. Getting tailored applications or applications up and running to get in touch with users and customers all over the world is now within easy reach for small outfits – without any investment. My misunderstanding For a long time, I was under the impression that the essence of APEX was that the business could create applications themselves – meaning that business ‘people’ would actually go into APEX to create the application. To me APEX was too much of a developers’ tool to see that happen – apart from the odd business analyst who missed his or her calling as an IT developer. Having looked at various other cloud based development offerings – including Force.com, Mendix, WaveMaker, WorkXpress, OrangeScape, Caspio and Cordys- I have come to realize my mistake. All these platforms are positioned for 'the business' but require a fair amount of coding and technical expertise. However, they make the business happy nevertheless, because they allow the  business to completely circumvent the IT department. That is the essence. Not having to go through the red tape, not having to wait for IT staff who (justifiably) need weeks or months to provide an environment, not having to deal with administrators (again, justifiably) refusing to take on that 'strange environment'. Being able to think of an initiative and turn into action right away. The business does not have to build the application - it can easily hire some external developers or even that nerdy boy next door. They can get started, get an application up and running and invite users in – especially external users such as customers. They will worry later about upgrades and life cycle management and integration. To get applications up and running quickly and start turning ideas into action and results rightaway. That is the key selling point for all these cloud offerings, including APEX from the Cloud. And it is a compelling story. For APEX probably even more so than for the others. While I consider APEX a somewhat proprietary framework compared with ‘regular’ Java/JEE web development (or even .NET and PHP  development), it is still far more open than most cloud environments. APEX is SQL and PL/SQL based – nothing special about those languages – and can run just as easily on site as in the cloud. It has been around since 2004 (that is not including several predecessors that fed straight into APEX) so it can be considered pretty mature. Oracle as a company seems pretty stable – so investments in its technology are bound to last for some time to come. By the way: neither APEX nor the other Cloud DevaaS offerings are targeted at creating applications with enormous life times. They fit into a trend of agile development and rapid life cycle management, with fairly light weight user interfaces that quickly adapt to taste, technology trends and functional requirements and that are easily replaced. APEX and ADF – a match made in heaven?! (or at least in the sky) Note that using APEX only for cloud based database with REST-ful Services is also a perfectly viable scenario: any UI – mobile or browser based – capable of consuming REST-ful services can be created against such a business tier. Creating an ADF Mobile application for example that runs aginst REST-ful services is a best practice for mobile development. Such REST-ful services can be consumed from any service provider – including the Cloud based APEX powered REST-ful services running against the Oracle Cloud Database Service! The ADF Mobile architecture overview can easily be morphed to fit the APEX services in – allowing for a cloud based mobile app: Want to learn more about Oracle Database Cloud Service or Oracle Cloud, just visit cloud.oracle.com  or oracle.com/cloud. Repost of a blog entry by Rick Greenwald, Director of Product Management, Oracle Database Cloud Service.

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  • Using SQL Execution Plans to discover the Swedish alphabet

    - by Rob Farley
    SQL Server is quite remarkable in a bunch of ways. In this post, I’m using the way that the Query Optimizer handles LIKE to keep it SARGable, the Execution Plans that result, Collations, and PowerShell to come up with the Swedish alphabet. SARGability is the ability to seek for items in an index according to a particular set of criteria. If you don’t have SARGability in play, you need to scan the whole index (or table if you don’t have an index). For example, I can find myself in the phonebook easily, because it’s sorted by LastName and I can find Farley in there by moving to the Fs, and so on. I can’t find everyone in my suburb easily, because the phonebook isn’t sorted that way. I can’t even find people who have six letters in their last name, because also the book is sorted by LastName, it’s not sorted by LEN(LastName). This is all stuff I’ve looked at before, including in the talk I gave at SQLBits in October 2010. If I try to find everyone who’s names start with F, I can do that using a query a bit like: SELECT LastName FROM dbo.PhoneBook WHERE LEFT(LastName,1) = 'F'; Unfortunately, the Query Optimizer doesn’t realise that all the entries that satisfy LEFT(LastName,1) = 'F' will be together, and it has to scan the whole table to find them. But if I write: SELECT LastName FROM dbo.PhoneBook WHERE LastName LIKE 'F%'; then SQL is smart enough to understand this, and performs an Index Seek instead. To see why, I look further into the plan, in particular, the properties of the Index Seek operator. The ToolTip shows me what I’m after: You’ll see that it does a Seek to find any entries that are at least F, but not yet G. There’s an extra Predicate in there (a Residual Predicate if you like), which checks that each LastName is really LIKE F% – I suppose it doesn’t consider that the Seek Predicate is quite enough – but most of the benefit is seen by its working out the Seek Predicate, filtering to just the “at least F but not yet G” section of the data. This got me curious though, particularly about where the G comes from, and whether I could leverage it to create the Swedish alphabet. I know that in the Swedish language, there are three extra letters that appear at the end of the alphabet. One of them is ä that appears in the word Västerås. It turns out that Västerås is quite hard to find in an index when you’re looking it up in a Swedish map. I talked about this briefly in my five-minute talk on Collation from SQLPASS (the one which was slightly less than serious). So by looking at the plan, I can work out what the next letter is in the alphabet of the collation used by the column. In other words, if my alphabet were Swedish, I’d be able to tell what the next letter after F is – just in case it’s not G. It turns out it is… Yes, the Swedish letter after F is G. But I worked this out by using a copy of my PhoneBook table that used the Finnish_Swedish_CI_AI collation. I couldn’t find how the Query Optimizer calculates the G, and my friend Paul White (@SQL_Kiwi) tells me that it’s frustratingly internal to the QO. He’s particularly smart, even if he is from New Zealand. To investigate further, I decided to do some PowerShell, leveraging the Get-SqlPlan function that I blogged about recently (make sure you also have the SqlServerCmdletSnapin100 snap-in added). I started by indicating that I was going to use Finnish_Swedish_CI_AI as my collation of choice, and that I’d start whichever letter cam straight after the number 9. I figure that this is a cheat’s way of guessing the first letter of the alphabet (but it doesn’t actually work in Unicode – luckily I’m using varchar not nvarchar. Actually, there are a few aspects of this code that only work using ASCII, so apologies if you were wanting to apply it to Greek, Japanese, etc). I also initialised my $alphabet variable. $collation = 'Finnish_Swedish_CI_AI'; $firstletter = '9'; $alphabet = ''; Now I created the table for my test. A single field would do, and putting a Clustered Index on it would suffice for the Seeks. Invoke-Sqlcmd -server . -data tempdb -query "create table dbo.collation_test (col varchar(10) collate $collation primary key);" Now I get into the looping. $c = $firstletter; $stillgoing = $true; while ($stillgoing) { I construct the query I want, seeking for entries which start with whatever $c has reached, and get the plan for it: $query = "select col from dbo.collation_test where col like '$($c)%';"; [xml] $pl = get-sqlplan $query "." "tempdb"; At this point, my $pl variable is a scary piece of XML, representing the execution plan. A bit of hunting through it showed me that the EndRange element contained what I was after, and that if it contained NULL, then I was done. $stillgoing = ($pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange -ne $null); Now I could grab the value out of it (which came with apostrophes that needed stripping), and append that to my $alphabet variable.   if ($stillgoing)   {  $c=$pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange.RangeExpressions.ScalarOperator.ScalarString.Replace("'","");     $alphabet += $c;   } Finally, finishing the loop, dropping the table, and showing my alphabet! } Invoke-Sqlcmd -server . -data tempdb -query "drop table dbo.collation_test;"; $alphabet; When I run all this, I see that the Swedish alphabet is ABCDEFGHIJKLMNOPQRSTUVXYZÅÄÖ, which matches what I see at Wikipedia. Interesting to see that the letters on the end are still there, even with Case Insensitivity. Turns out they’re not just “letters with accents”, they’re letters in their own right. I’m sure you gave up reading long ago, and really aren’t that fazed about the idea of doing this using PowerShell. I chose PowerShell because I’d already come up with an easy way of grabbing the estimated plan for a query, and PowerShell does allow for easy navigation of XML. I find the most interesting aspect of this as the fact that the Query Optimizer uses the next letter of the alphabet to maintain the SARGability of LIKE. I’m hoping they do something similar for a whole bunch of operations. Oh, and the fact that you know how to find stuff in the IKEA catalogue. Footnote: If you are interested in whether this works in other languages, you might want to consider the following screenshot, which shows that in principle, it should work with Japanese. It might be a bit harder to run this in PowerShell though, as I’m not sure how it translates. In Hiragana, the Japanese alphabet starts ?, ?, ?, ?, ?, ...

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  • My Thoughts On the Xbox 180

    - by Chris Gardner
    Originally posted on: http://geekswithblogs.net/freestylecoding/archive/2013/06/21/my-thoughts-on-the-xbox-180.aspx Everyone seems to be putting their 0.00237 cents into the wishing well over Microsoft's recent decision to reverse the DRM policy on the Xbox One. However, there have been a few issues that nobody has touched. As such, I have decided to dig 0.00237 cents out of my pocket. First, let me be clear about this point. I do not support the decision to reverse the DRM policy on the Xbox One. I wanted that point to be expressed first and unambiguously. I will say it again. I do not support the decision to reverse the DRM policy on the Xbox One. Now that I have that out of the way, let me go into my rationale. This decision removes most of the cool features that enticed me to pre-order the console. No, I didn't cancel my pre-order. There is still five months before the release of the console, and there is still a plethora of information that we, as consumers, do not have. With that, it should be noted that much of the talk in this post is speculation and rhetoric. I do not have any insider information that you do not possess. The persistent connection would have allowed the console to do many of the functions for which we have been begging. That demo where someone was playing Ryse, seamlessly accepted a multiplayer challenge in Killer Instinct, played the match (and a rematch,) and then jumped back into Ryse. That's gone, if you bought the game on disc. The new, DRM free system will require the disc in the system to play a game. That bullet point where one Xbox Live account could have up to 10 slave accounts so families could play together, no matter where they were located. That's gone as well. The promise of huge, expansive, dynamically changing worlds that was brought to us with the power of cloud computing. Well, "the people" didn't want there to be a forced, persistent connection. As such, developers can't rely on a connection and, as such, that feature is gone. This is akin to the removal of the hard drive on the Xbox 360. The list continues, but the enthusiast press has enumerated the list far better than I wish. All of this is because the Xbox team saw the HUGE success of Steam and decided to borrow a few ideas. Yes, Steam. The service that everyone hated for the first six months (for the same reasons the Xbox One is getting flack.) There was an initial growing pain. However, it is now lauded as the way games distribution should be handled. Unless you are Microsoft. I do find it curious that many of the features were originally announced for the PS4 during its unveiling. However, much of that was left strangely absent for Sony's E3 press conference. Instead, we received a single, static slide that basically said the exact opposite of Microsoft's plans. It is not farfetched to believe that slide came into existence during the approximately seven hours between the two media briefings. The thing that majorly annoys me over this whole kerfuffle is that the single thing that caused the call to arms is, really, not an issue. Microsoft never said they were going to block used sales. They said it was up to the publisher to make that decision. This would have allowed publishers to reclaim some of the costs of development in subsequent sales of the product. If you sell your game to GameStop for 7 USD, GameStop is going to sell it for 55 USD. That is 48 USD pure profit for them. Some publishers asked GameStop for a small cut. Was this a huge, money grubbing scheme? Well, yes, but the idea was that they have to handle server infrastructure for dormant accounts, etc. Of course, GameStop flatly refused, and the Online Pass was born. Fortunately, this trend didn’t last, and most publishers have stopped the practice. The ability to sell "licenses" has already begun to be challenged. Are you living in the EU? If so, companies must allow you to sell digital property. With this precedent in place, it's only a matter of time before other areas follow suit. If GameStop were smart, they should have immediately contacted every publisher out there to get the rights to become a clearing house for these licenses. Then, they keep their business model and could reduce their brick and mortar footprint. The digital landscape is changing. We need to not block this process. As Seth MacFarlane best said "Some issues are so important that you should drag people kicking and screaming." I believe this was said on an episode of Real Time with Bill Maher about the issue of Gay Marriages. Much like the original source, this is an issue that we need to drag people to the correct, progressive position. Microsoft, as a company, actually has the resources to weather the transition period. They have a great pool of first and second party developers that can leverage this new framework to prove the validity. Over time, the third party developers will get excited to use these tools. As an old C++ guy, I resisted C# for years. Now, I think it's one of the best languages I've ever used. I have a server room and a Co-Lo full of servers, so I originally didn't see the value in Azure. Now, I wish I could move every one of my projects into the cloud. I still LOVE getting physical packaging, which my music and games collection will proudly attest. However, I have started to see the value in pure digital, and have found ways to integrate this into the ways I consume those products. I can, honestly, understand how some parts of the population would be very apprehensive about this new landscape. There were valid arguments about people with no internet access. There are ways to combat these problems. These methods do not require us to throw the baby out with the bathwater. However, the number of people in the computer industry that I have seen cry foul is truly appalling. We are the forward looking people that help show how technology can improve people's lives. If we can't see the value of the brief pain involved with an exciting new ecosystem, than who will?

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  • C#: LINQ vs foreach - Round 1.

    - by James Michael Hare
    So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

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  • CodePlex Daily Summary for Wednesday, June 15, 2011

    CodePlex Daily Summary for Wednesday, June 15, 2011Popular ReleasesTerraria World Viewer: Version 1.2: Update June 15thNew User Interface Map drawing will not cause the program to freeze anymore Fixed the "Draw Symbols" (now called "Markers") checkbox not having any effectMVC Controls Toolkit: Mvc Controls Toolkit 1.1.5 RC: Added Extended Dropdown allows a prompt item to be inserted as first element. RequiredAttribute, if present, trggers if no element is chosen Client side javascript function to set/get the values of DateTimeInput, TypedTextBox, TypedEditDisplay, and to bind/unbind a "change" handler The selected page in the pager is applied the attribute selected-page="selected" that can be used in the definition of CSS rules to style the selected page items controls now interpret a null value as an empr...Umbraco CMS: Umbraco CMS 5.0 CTP 1: Umbraco 5 Community Technology Preview Umbraco 5 will be the next version of everyone's favourite, friendly ASP.NET CMS that already powers over 100,000 websites worldwide. Try out our first CTP of version 5 today! If you're new to Umbraco and would like to get a quick low-down on our popular and easy-to-learn approach to content management, check out our intro video here. What's in the v5 CTP box? This is a preview version of version 5 and includes support for the following familiar Umbr...Ribbon Browser for Microsoft Dynamics CRM 2011: Ribbon Browser (1.0.514.30): Initial releaseTerrariViewer: TerrariViewer v3.0 [Terraria Inventory Editor]: In this version, I did an overhaul of the GUI of the program. The only pop-up window you will receive now is a warning box for for when you click on the "Delete" button. Everything has been integrated into the tabs on the form. I added every item included with v1.0.4 of Terraria and added the option to set inventory/bank slots to "No Item". This WILL work with characters that have not been opened in v1.0.4patterns & practices: Project Silk: Project Silk Community Drop 11 - June 14, 2011: Changes from previous drop: Many code changes: please see the readme.mht for details. New "Client Data Management and Caching" chapter. Updated "Application Notifications" chapter. Updated "Architecture" chapter. Updated "jQuery UI Widget" chapter. Updated "Widget QuickStart" appendix and code. Guidance Chapters Ready for Review The Word documents for the chapters are included with the source code in addition to the CHM to help you provide feedback. The PDF is provided as a separat...Orchard Project: Orchard 1.2: Build: 1.2.41 Published: 6/14/2010 How to Install Orchard To install Orchard using Web PI, follow these instructions: http://www.orchardproject.net/docs/Installing-Orchard.ashx. Web PI will detect your hardware environment and install the application. Alternatively, to install the release manually, download the Orchard.Web.1.2.41.zip file. http://orchardproject.net/docs/Manually-installing-Orchard-zip-file.ashx The zip contents are pre-built and ready-to-run. Simply extract the contents o...PowerGUI Visual Studio Extension: PowerGUI VSX 1.3.4: Changes - Got rid of suppressed exceptions on assemblies loading at project startup - Fixed Issue #28535 "No Print Support" - Enabled IntelliSence commands wich are supported by ActiPro Syntax Editor control: ToggleBookmark, NextBookmark, PreviousBookmark, ShowMemberList - Added missing Import directives in PS Script project template - Fixed exception occurring on debug start - Fixed an issue: after creating a new PS project, a debugging session hung being run for the second timeSnippet Designer: Snippet Designer 1.4.0: Snippet Designer 1.4.0 for Visual Studio 2010 Change logSnippet Explorer ChangesReworked language filter UI to work better in the side bar. Added result count drop down which lets you choose how many results to see. Language filter and result count choices are persisted after Visual Studio is closed. Added file name to search criteria. Search is now case insensitive. Snippet Editor Changes Snippet Editor ChangesAdded menu option for the $end$ symbol which indicates where the c...SizeOnDisk: 1.0.9.0: Can handle Right-To-Left languages (issue 316) About box (issue 310) New language: Deutsch (thanks to kyoka) Fix: file and folder context menuDropBox Linker: DropBox Linker 1.1: Added different popup descriptions for actions (copy/append/update/remove) Added popup timeout control (with live preview) Added option to overwrite clipboard with the last link only Notification popup closes on user click Notification popup default timeout increased to 3 sec. Added codeplex link to about .NET Framework 4.0 Client Profile requiredWCF Community Site: WCF Express Interop Bindings 1.0: Welcome to the first release of the WCF Express Interop BindingsThis project provides a starter kit for WCF service developers wishing to connect with Java clients in WebSphere, WebLogic, Metro and Apache. It supports security, MTOM and RM features. For more information see the Landing page We welcome your feedback (Topic: Interop Bindings). Please submit any feature requests / bug fixes via the issue tracker. FeaturesVSIX Installer WCF Bindings for Oracle WebLogic, Oracle Metro, IBM WebS...Mobile Device Detection and Redirection: 1.0.4.1: Stable Release 51 Degrees.mobi Foundation is the best way to detect and redirect mobile devices and their capabilities on ASP.NET and is being used on thousands of websites worldwide. We’re highly confident in our software and we recommend all users update to this version. Changes to Version 1.0.4.1Changed the BlackberryHandler and BlackberryVersion6Handler to have equal CONFIDENCE values to ensure they both get a chance at detecting BlackBerry version 4&5 and version 6 devices. Prior to thi...Kouak - HTTP File Share Server: Kouak Beta 3 - Clean: Some critical bug solved and dependecy problems There's 3 package : - The first, contains the cli server and the graphical server. - The second, only the cli server - The third, only the graphical client. It's a beta release, so don't hesitate to emmit issue ;pRawr: Rawr 4.1.06: This is the Downloadable WPF version of Rawr!For web-based version see http://elitistjerks.com/rawr.php You can find the version notes at: http://rawr.codeplex.com/wikipage?title=VersionNotes Rawr AddonWe now have a Rawr Official Addon for in-game exporting and importing of character data hosted on Curse. The Addon does not perform calculations like Rawr, it simply shows your exported Rawr data in wow tooltips and lets you export your character to Rawr (including bag and bank items) like Char...AcDown????? - Anime&Comic Downloader: AcDown????? v3.0 Beta6: ??AcDown?????????????,?????????????,????、????。?????Acfun????? ????32??64? Windows XP/Vista/7 ????????????? ??:????????Windows XP???,?????????.NET Framework 2.0???(x86)?.NET Framework 2.0???(x64),?????"?????????"??? ??v3.0 Beta6 ?????(imanhua.com)????? ???? ?? ??"????","?????","?????","????"?????? "????"?????"????????"?? ??????????? ?????????????? ?????????????/???? ?? ????Windows 7???????????? ????????? ?? ????????????? ???????/??????????? ???????????? ?? ?? ?????(imanh...Pulse: Pulse Beta 2: - Added new wallpapers provider http://wallbase.cc. Supports english search, multiple keywords* - Improved font rendering in Options window - Added "Set wallpaper as logon background" option* - Fixed crashes if there is no internet connection - Fixed: Rewalls downloads empty images sometimes - Added filters* Note 1: wallbase provider supports only english search. Rewalls provider supports only russian search but Pulse automatically translates your english keyword into russian using Google Tr...WPF Application Framework (WAF): WPF Application Framework (WAF) 2.0.0.7: Version: 2.0.0.7 (Milestone 7): This release contains the source code of the WPF Application Framework (WAF) and the sample applications. Requirements .NET Framework 4.0 (The package contains a solution file for Visual Studio 2010) The unit test projects require Visual Studio 2010 Professional Remark The sample applications are using Microsoft’s IoC container MEF. However, the WPF Application Framework (WAF) doesn’t force you to use the same IoC container in your application. You can use ...SimplePlanner: v2.0b: For 2011-2012 Sem 1 ???2011-2012 ????Visual Studio 2010 Help Downloader: 1.0.0.3: Domain name support for proxy Cleanup old packages bug Writing to EventLog with UAC enabled bug Small fixes & RefactoringNew Projects360U: 360UAd Configuration + Rotator for Windows Phone: Ad Configuration and Rotator for Windows Phone is a set of classes and controls which allow you to remotely manage advertising providers used inside your Windows Phone application. Advertising providers can be plugged in on an 'as needed' so application only ship with the providers being used.CommerceShopSystem: CommerceShopSystemContour strikes again: Collection of extensions for the Umbraco Contour form builderFarseer Physics & GLEED2D Link: This project includes c# files usable to implement the Farseer Physics engine in a level created using GLEED2D.FolderComparer: This DLL holds an extension of the DirectoryInfo class. It contains a logic that helps compare the contents of two folders. HierList Hierarchial Outline ASP.NET Server Control ( using UL or OL and LI ): The HierList ASP WebControl generates a hierarchial list using the UL, OL, and LI html tags. Images Organizator: A C# .Net program that organizes all pictures in a folder by date.KiggDemo: i study kiggLavieOrnamentos: LavieOrnamentos is a MVC project written in C# for a standard business website. I plan to use it as a base for a bigger project, a standard business site framework targeting small companies that just want to display their products and latest news.Multiple Choice Training Application: This is an ASP.Net (VB.Net) Web based training application. This application can be configured to ask multiple choice questions for multiple groups, score based on percentage, create completion certificates and be completely managed via a web interface,Orchard Windows Authentication: This module allows Windows domain users to be authenticated in Orchard.Party Estimator: Party Estimator is a training project based on requirements from O'Reilly's _Head First C#_, and is not intended for widespread use. SharePoint Enforcer - Ensuring large sites comply with standards: SharePoint Enforcer is a utility that aids in governance of large SharePoint sites to ensure that the sites comply with various business rules that have been created to keep the site from growing out of control.SharePoint WarmUp Tool (Claims+FBA): This tools is for warming up (waking) SharPoint sites. It addresses the issue of a 403 forbidden error when the SharePoint web app is in claims mode and FBA. It uses Windows authentication to warm up the sites and bypasses the FBA login redirection causing the 403 forbidden error.Super Mario Limitless: Super Mario Limitless is an in-production Super Mario level engine. It allows you to play your own levels and worlds, play others' levels and worlds, and even play online. With limitless features, you'll spend hours playing and creating.VB.NET ASP.NET MVC 2 - Music Store: This project is a port using the VB language with ASP.NET MVC 2 of the MusicStore application that can be found at : http://mvcmusicstore.codeplex.com/ Veni, Vedi, Velcro...: A personal phone 7 social media app that shows basic elements of design, ad model, panorama etc.XMLServiceMonitor: A Windows service (VB.Net) that allows the monitoring of failure of Servers, Services, Applications, Scheduled Tasks and SQL Jobs. The service is configurable with simple XML files and sends out email notifications of failures.

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  • Is RTD Stateless or Stateful?

    - by [email protected]
    Yes.   A stateless service is one where each request is an independent transaction that can be processed by any of the servers in a cluster.  A stateful service is one where state is kept in a server's memory from transaction to transaction, thus necessitating the proper routing of requests to the right server. The main advantage of stateless systems is simplicity of design. The main advantage of stateful systems is performance. I'm often asked whether RTD is a stateless or stateful service, so I wanted to clarify this issue in depth so that RTD's architecture will be properly understood. The short answer is: "RTD can be configured as a stateless or stateful service." The performance difference between stateless and stateful systems can be very significant, and while in a call center implementation it may be reasonable to use a pure stateless configuration, a web implementation that produces thousands of requests per second is practically impossible with a stateless configuration. RTD's performance is orders of magnitude better than most competing systems. RTD was architected from the ground up to achieve this performance. Features like automatic and dynamic compression of prediction models, automatic translation of metadata to machine code, lack of interpreted languages, and separation of model building from decisioning contribute to achieving this performance level. Because  of this focus on performance we decided to have RTD's default configuration work in a stateful manner. By being stateful RTD requests are typically handled in a few milliseconds when repeated requests come to the same session. Now, those readers that have participated in implementations of RTD know that RTD's architecture is also focused on reducing Total Cost of Ownership (TCO) with features like automatic model building, automatic time windows, automatic maintenance of database tables, automatic evaluation of data mining models, automatic management of models partitioned by channel, geography, etcetera, and hot swapping of configurations. How do you reconcile the need for a low TCO and the need for performance? How do you get the performance of a stateful system with the simplicity of a stateless system? The answer is that you make the system behave like a stateless system to the exterior, but you let it automatically take advantage of situations where being stateful is better. For example, one of the advantages of stateless systems is that you can route a message to any server in a cluster, without worrying about sending it to the same server that was handling the session in previous messages. With an RTD stateful configuration you can still route the message to any server in the cluster, so from the point of view of the configuration of other systems, it is the same as a stateless service. The difference though comes in performance, because if the message arrives to the right server, RTD can serve it without any external access to the session's state, thus tremendously reducing processing time. In typical implementations it is not rare to have high percentages of messages routed directly to the right server, while those that are not, are easily handled by forwarding the messages to the right server. This architecture usually provides the best of both worlds with performance and simplicity of configuration.   Configuring RTD as a pure stateless service A pure stateless configuration requires session data to be persisted at the end of handling each and every message and reloading that data at the beginning of handling any new message. This is of course, the root of the inefficiency of these configurations. This is also the reason why many "stateless" implementations actually do keep state to take advantage of a request coming back to the same server. Nevertheless, if the implementation requires a pure stateless decision service, this is easy to configure in RTD. The way to do it is: Mark every Integration Point to Close the session at the end of processing the message In the Session entity persist the session data on closing the session In the session entity check if a persisted version exists and load it An excellent solution for persisting the session data is Oracle Coherence, which provides a high performance, distributed cache that minimizes the performance impact of persisting and reloading the session. Alternatively, the session can be persisted to a local database. An interesting feature of the RTD stateless configuration is that it can cope with serializing concurrent requests for the same session. For example, if a web page produces two requests to the decision service, these requests could come concurrently to the decision services and be handled by different servers. Most stateless implementation would have the two requests step onto each other when saving the state, or fail one of the messages. When properly configured, RTD will make one message wait for the other before processing.   A Word on Context Using the context of a customer interaction typically significantly increases lift. For example, offer success in a call center could double if the context of the call is taken into account. For this reason, it is important to utilize the contextual information in decision making. To make the contextual information available throughout a session it needs to be persisted. When there is a well defined owner for the information then there is no problem because in case of a session restart, the information can be easily retrieved. If there is no official owner of the information, then RTD can be configured to persist this information.   Once again, RTD provides flexibility to ensure high performance when it is adequate to allow for some loss of state in the rare cases of server failure. For example, in a heavy use web site that serves 1000 pages per second the navigation history may be stored in the in memory session. In such sites it is typical that there is no OLTP that stores all the navigation events, therefore if an RTD server were to fail, it would be possible for the navigation to that point to be lost (note that a new session would be immediately established in one of the other servers). In most cases the loss of this navigation information would be acceptable as it would happen rarely. If it is desired to save this information, RTD would persist it every time the visitor navigates to a new page. Note that this practice is preferred whether RTD is configured in a stateless or stateful manner.  

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  • SQL SERVER – Weekly Series – Memory Lane – #032

    - by Pinal Dave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Complete Series of Database Coding Standards and Guidelines SQL SERVER Database Coding Standards and Guidelines – Introduction SQL SERVER – Database Coding Standards and Guidelines – Part 1 SQL SERVER – Database Coding Standards and Guidelines – Part 2 SQL SERVER Database Coding Standards and Guidelines Complete List Download Explanation and Example – SELF JOIN When all of the data you require is contained within a single table, but data needed to extract is related to each other in the table itself. Examples of this type of data relate to Employee information, where the table may have both an Employee’s ID number for each record and also a field that displays the ID number of an Employee’s supervisor or manager. To retrieve the data tables are required to relate/join to itself. Insert Multiple Records Using One Insert Statement – Use of UNION ALL This is very interesting question I have received from new developer. How can I insert multiple values in table using only one insert? Now this is interesting question. When there are multiple records are to be inserted in the table following is the common way using T-SQL. Function to Display Current Week Date and Day – Weekly Calendar Straight blog post with script to find current week date and day based on the parameters passed in the function.  2008 In my beginning years, I have almost same confusion as many of the developer had in their earlier years. Here are two of the interesting question which I have attempted to answer in my early year. Even if you are experienced developer may be you will still like to read following two questions: Order Of Column In Index Order of Conditions in WHERE Clauses Example of DISTINCT in Aggregate Functions Have you ever used DISTINCT with the Aggregation Function? Here is a simple example about how users can do it. Create a Comma Delimited List Using SELECT Clause From Table Column Straight to script example where I explained how to do something easy and quickly. Compound Assignment Operators SQL SERVER 2008 has introduced new concept of Compound Assignment Operators. Compound Assignment Operators are available in many other programming languages for quite some time. Compound Assignment Operators is operator where variables are operated upon and assigned on the same line. PIVOT and UNPIVOT Table Examples Here is a very interesting question – the answer to the question can be YES or NO both. “If we PIVOT any table and UNPIVOT that table do we get our original table?” Read the blog post to get the explanation of the question above. 2009 What is Interim Table – Simple Definition of Interim Table The interim table is a table that is generated by joining two tables and not the final result table. In other words, when two tables are joined they create an interim table as resultset but the resultset is not final yet. It may be possible that more tables are about to join on the interim table, and more operations are still to be applied on that table (e.g. Order By, Having etc). Besides, it may be possible that there is no interim table; sometimes final table is what is generated when the query is run. 2010 Stored Procedure and Transactions If Stored Procedure is transactional then, it should roll back complete transactions when it encounters any errors. Well, that does not happen in this case, which proves that Stored Procedure does not only provide just the transactional feature to a batch of T-SQL. Generate Database Script for SQL Azure When talking about SQL Azure the most common complaint I hear is that the script generated from stand-along SQL Server database is not compatible with SQL Azure. This was true for some time for sure but not any more. If you have SQL Server 2008 R2 installed you can follow the guideline below to generate a script which is compatible with SQL Azure. Convert IN to EXISTS – Performance Talk It is NOT necessary that every time when IN is replaced by EXISTS it gives better performance. However, in our case listed above it does for sure give better performance. You can read about this subject in the associated blog post. Subquery or Join – Various Options – SQL Server Engine Knows the Best Every single time whenever there is a performance tuning exercise, I hear the conversation from developer where some prefer subquery and some prefer join. In this two part blog post, I explain the same in the detail with examples. Part 1 | Part 2 Merge Operations – Insert, Update, Delete in Single Execution 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. 2011 Puzzle – Statistics are not updated but are Created Once Here is the quick scenario about my setup. Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated – WHY? Question to You – When to use Function and When to use Stored Procedure Personally, I believe that they are both different things - they cannot be compared. I can say, it will be like comparing apples and oranges. Each has its own unique use. However, they can be used interchangeably at many times and in real life (i.e., production environment). I have personally seen both of these being used interchangeably many times. This is the precise reason for asking this question. 2012 In year 2012 I had two interesting series ran on the blog. If there is no fun in learning, the learning becomes a burden. For the same reason, I had decided to build a three part quiz around SEQUENCE. The quiz was to identify the next value of the sequence. I encourage all of you to take part in this fun quiz. Guess the Next Value – Puzzle 1 Guess the Next Value – Puzzle 2 Guess the Next Value – Puzzle 3 Guess the Next Value – Puzzle 4 Simple Example to Configure Resource Governor – Introduction to Resource Governor Resource Governor is a feature which can manage SQL Server Workload and System Resource Consumption. We can limit the amount of CPU and memory consumption by limiting /governing /throttling on the SQL Server. If there are different workloads running on SQL Server and each of the workload needs different resources or when workloads are competing for resources with each other and affecting the performance of the whole server resource governor is a very important task. Tricks to Replace SELECT * with Column Names – SQL in Sixty Seconds #017 – Video  Retrieves unnecessary columns and increases network traffic When a new columns are added views needs to be refreshed manually Leads to usage of sub-optimal execution plan Uses clustered index in most of the cases instead of using optimal index It is difficult to debug SQL SERVER – Load Generator – Free Tool From CodePlex The best part of this SQL Server Load Generator is that users can run multiple simultaneous queries again SQL Server using different login account and different application name. The interface of the tool is extremely easy to use and very intuitive as well. A Puzzle – Swap Value of Column Without Case Statement Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Oracle's Global Single Schema

    - by david.butler(at)oracle.com
    Maximizing business process efficiencies in a heterogeneous environment is very difficult. The difficulty stems from the fact that the various applications across the Information Technology (IT) landscape employ different integration standards, different message passing strategies, and different workflow engines. Vendors such as Oracle and others are delivering tools to help IT organizations manage the complexities introduced by these differences. But the one remaining intractable problem impacting efficient operations is the fact that these applications have different definitions for the same business data. Business data is your business information codified for computer programs to use. A good data model will represent the way your organization does business. The computer applications your organization deploys to improve operational efficiency are built to operate on the business data organized into this schema.  If the schema does not represent how you do business, the applications on that schema cannot provide the features you need to achieve the desired efficiencies. Business processes span these applications. Data problems break these processes rendering them far less efficient than they need to be to achieve organization goals. Thus, the expected return on the investment in these applications is never realized. The success of all business processes depends on the availability of accurate master data.  Clearly, the solution to this problem is to consolidate all the master data an organization uses to run its business. Then clean it up, augment it, govern it, and connect it back to the applications that need it. Until now, this obvious solution has been difficult to achieve because no one had defined a data model sufficiently broad, deep and flexible enough to support transaction processing on all key business entities and serve as a master superset to all other operational data models deployed in heterogeneous IT environments. Today, the situation has changed. Oracle has created an operational data model (aka schema) that can support accurate and consistent master data across heterogeneous IT systems. This is foundational for providing a way to consolidate and integrate master data without having to replace investments in existing applications. This Global Single Schema (GSS) represents a revolutionary breakthrough that allows for true master data consolidation. Oracle has deep knowledge of applications dating back to the early 1990s.  It developed applications in the areas of Supply Chain Management (SCM), Product Lifecycle Management (PLM), Enterprise Resource Planning (ERP), Customer Relationship Management (CRM), Human Capital Management (HCM), Financials and Manufacturing. In addition, Oracle applications were delivered for key industries such as Communications, Financial Services, Retail, Public Sector, High Tech Manufacturing (HTM) and more. Expertise in all these areas drove requirements for GSS. The following figure illustrates Oracle's unique position that enabled the creation of the Global Single Schema. GSS Requirements Gathering GSS defines all the key business entities and attributes including Customers, Contacts, Suppliers, Accounts, Products, Services, Materials, Employees, Installed Base, Sites, Assets, and Inventory to name just a few. In addition, Oracle delivers GSS pre-integrated with a wide variety of operational applications.  Business Process Automation EBusiness is about maximizing operational efficiency. At the highest level, these 'operations' span all that you do as an organization.  The following figure illustrates some of these high-level business processes. Enterprise Business Processes Supplies are procured. Assets are maintained. Materials are stored. Inventory is accumulated. Products and Services are engineered, produced and sold. Customers are serviced. And across this entire spectrum, Employees do the procuring, supporting, engineering, producing, selling and servicing. Not shown, but not to be overlooked, are the accounting and the financial processes associated with all this procuring, manufacturing, and selling activity. Supporting all these applications is the master data. When this data is fragmented and inconsistent, the business processes fail and inefficiencies multiply. But imagine having all the data under these operational business processes in one place. ·            The same accurate and timely customer data will be provided to all your operational applications from the call center to the point of sale. ·            The same accurate and timely supplier data will be provided to all your operational applications from supply chain planning to procurement. ·            The same accurate and timely product information will be available to all your operational applications from demand chain planning to marketing. You would have a single version of the truth about your assets, financial information, customers, suppliers, employees, products and services to support your business automation processes as they flow across your business applications. All company and partner personnel will access the same exact data entity across all your channels and across all your lines of business. Oracle's Global Single Schema enables this vision of a single version of the truth across the heterogeneous operational applications supporting the entire enterprise. Global Single Schema Oracle's Global Single Schema organizes hundreds of thousands of attributes into 165 major schema objects supporting over 180 business application modules. It is designed for international operations, and extensibility.  The schema is delivered with a full set of public Application Programming Interfaces (APIs) and an Integration Repository with modern Service Oriented Architecture interfaces to make data available as a services (DaaS) to business processes and enable operations in heterogeneous IT environments. ·         Key tables can be extended with unlimited numbers of additional attributes and attribute groups for maximum flexibility.  o    This enables model extensions that reflect business entities unique to your organization's operations. ·         The schema is multi-organization enabled so data manipulation can be controlled along organizational boundaries. ·         It uses variable byte Unicode to support over 31 languages. ·         The schema encodes flexible date and flexible address formats for easy localizations. No matter how complex your business is, Oracle's Global Single Schema can hold your business objects and support your global operations. Oracle's Global Single Schema identifies and defines the business objects an enterprise needs within the context of its business operations. The interrelationships between the business objects are also contained within the GSS data model. Their presence expresses fundamental business rules for the interaction between business entities. The following figure illustrates some of these connections.   Interconnected Business Entities Interconnecte business processes require interconnected business data. No other MDM vendor has this capability. Everyone else has either one entity they can master or separate disconnected models for various business entities. Higher level integrations are made available, but that is a weak architectural alternative to data level integration in this critically important aspect of Master Data Management.    

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  • SQL SERVER – Using expressor Composite Types to Enforce Business Rules

    - by pinaldave
    One of the features that distinguish the expressor Data Integration Platform from other products in the data integration space is its concept of composite types, which provide an effective and easily reusable way to clearly define the structure and characteristics of data within your application.  An important feature of the composite type approach is that it allows you to easily adjust the content of a record to its ultimate purpose.  For example, a record used to update a row in a database table is easily defined to include only the minimum set of columns, that is, a value for the key column and values for only those columns that need to be updated. Much like a class in higher level programming languages, you can also use the composite type as a way to enforce business rules onto your data by encapsulating a datum’s name, data type, and constraints (for example, maximum, minimum, or acceptable values) as a single entity, which ensures that your data can not assume an invalid value.  To what extent you use this functionality is a decision you make when designing your application; the expressor design paradigm does not force this approach on you. Let’s take a look at how these features are used.  Suppose you want to create a group of applications that maintain the employee table in your human resources database. Your table might have a structure similar to the HumanResources.Employee table in the AdventureWorks database.  This table includes two columns, EmployeID and rowguid, that are maintained by the relational database management system; you cannot provide values for these columns when inserting new rows into the table. Additionally, there are columns such as VacationHours and SickLeaveHours that you might choose to update for all employees on a monthly basis, which justifies creation of a dedicated application. By creating distinct composite types for the read, insert and update operations against this table, you can more easily manage this table’s content. When developing this application within expressor Studio, your first task is to create a schema artifact for the database table.  This process is completely driven by a wizard, only requiring that you select the desired database schema and table.  The resulting schema artifact defines the mapping of result set records to a record within the expressor data integration application.  The structure of the record within the expressor application is a composite type that is given the default name CompositeType1.  As you can see in the following figure, all columns from the table are included in the result set and mapped to an identically named attribute in the default composite type. If you are developing an application that needs to read this table, perhaps to prepare a year-end report of employees by department, you would probably not be interested in the data in the rowguid and ModifiedDate columns.  A typical approach would be to drop this unwanted data in a downstream operator.  But using an alternative composite type provides a better approach in which the unwanted data never enters your application. While working in expressor  Studio’s schema editor, simply create a second composite type within the same schema artifact, which you could name ReadTable, and remove the attributes corresponding to the unwanted columns. The value of an alternative composite type is even more apparent when you want to insert into or update the table.  In the composite type used to insert rows, remove the attributes corresponding to the EmployeeID primary key and rowguid uniqueidentifier columns since these values are provided by the relational database management system. And to update just the VacationHours and SickLeaveHours columns, use a composite type that includes only the attributes corresponding to the EmployeeID, VacationHours, SickLeaveHours and ModifiedDate columns. By specifying this schema artifact and composite type in a Write Table operator, your upstream application need only deal with the four required attributes and there is no risk of unintentionally overwriting a value in a column that does not need to be updated. Now, what about the option to use the composite type to enforce business rules?  If you review the composition of the default composite type CompositeType1, you will note that the constraints defined for many of the attributes mirror the table column specifications.  For example, the maximum number of characters in the NationaIDNumber, LoginID and Title attributes is equivalent to the maximum width of the target column, and the size of the MaritalStatus and Gender attributes is limited to a single character as required by the table column definition.  If your application code leads to a violation of these constraints, an error will be raised.  The expressor design paradigm then allows you to handle the error in a way suitable for your application.  For example, a string value could be truncated or a numeric value could be rounded. Moreover, you have the option of specifying additional constraints that support business rules unrelated to the table definition. Let’s assume that the only acceptable values for marital status are S, M, and D.  Within the schema editor, double-click on the MaritalStatus attribute to open the Edit Attribute window.  Then click the Allowed Values checkbox and enter the acceptable values into the Constraint Value text box. The schema editor is updated accordingly. There is one more option that the expressor semantic type paradigm supports.  Since the MaritalStatus attribute now clearly specifies how this type of information should be represented (a single character limited to S, M or D), you can convert this attribute definition into a shared type, which will allow you to quickly incorporate this definition into another composite type or into the description of an output record from a transform operator. Again, double-click on the MaritalStatus attribute and in the Edit Attribute window, click Convert, which opens the Share Local Semantic Type window that you use to name this shared type.  There’s no requirement that you give the shared type the same name as the attribute from which it was derived.  You should supply a name that makes it obvious what the shared type represents. In this posting, I’ve overviewed the expressor semantic type paradigm and shown how it can be used to make your application development process more productive.  The beauty of this feature is that you choose when and to what extent you utilize the functionality, but I’m certain that if you opt to follow this approach your efforts will become more efficient and your work will progress more quickly.  As always, I encourage you to download and evaluate expressor Studio for your current and future data integration needs. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: CodeProject, Pinal Dave, PostADay, SQL, SQL Authority, SQL Documentation, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • C# Performance Pitfall – Interop Scenarios Change the Rules

    - by Reed
    C# and .NET, overall, really do have fantastic performance in my opinion.  That being said, the performance characteristics dramatically differ from native programming, and take some relearning if you’re used to doing performance optimization in most other languages, especially C, C++, and similar.  However, there are times when revisiting tricks learned in native code play a critical role in performance optimization in C#. I recently ran across a nasty scenario that illustrated to me how dangerous following any fixed rules for optimization can be… The rules in C# when optimizing code are very different than C or C++.  Often, they’re exactly backwards.  For example, in C and C++, lifting a variable out of loops in order to avoid memory allocations often can have huge advantages.  If some function within a call graph is allocating memory dynamically, and that gets called in a loop, it can dramatically slow down a routine. This can be a tricky bottleneck to track down, even with a profiler.  Looking at the memory allocation graph is usually the key for spotting this routine, as it’s often “hidden” deep in call graph.  For example, while optimizing some of my scientific routines, I ran into a situation where I had a loop similar to: for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i]); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This loop was at a fairly high level in the call graph, and often could take many hours to complete, depending on the input data.  As such, any performance optimization we could achieve would be greatly appreciated by our users. After a fair bit of profiling, I noticed that a couple of function calls down the call graph (inside of ProcessElement), there was some code that effectively was doing: // Allocate some data required DataStructure* data = new DataStructure(num); // Call into a subroutine that passed around and manipulated this data highly CallSubroutine(data); // Read and use some values from here double values = data->Foo; // Cleanup delete data; // ... return bar; Normally, if “DataStructure” was a simple data type, I could just allocate it on the stack.  However, it’s constructor, internally, allocated it’s own memory using new, so this wouldn’t eliminate the problem.  In this case, however, I could change the call signatures to allow the pointer to the data structure to be passed into ProcessElement and through the call graph, allowing the inner routine to reuse the same “data” memory instead of allocating.  At the highest level, my code effectively changed to something like: DataStructure* data = new DataStructure(numberToProcess); for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i], data); } delete data; Granted, this dramatically reduced the maintainability of the code, so it wasn’t something I wanted to do unless there was a significant benefit.  In this case, after profiling the new version, I found that it increased the overall performance dramatically – my main test case went from 35 minutes runtime down to 21 minutes.  This was such a significant improvement, I felt it was worth the reduction in maintainability. In C and C++, it’s generally a good idea (for performance) to: Reduce the number of memory allocations as much as possible, Use fewer, larger memory allocations instead of many smaller ones, and Allocate as high up the call stack as possible, and reuse memory I’ve seen many people try to make similar optimizations in C# code.  For good or bad, this is typically not a good idea.  The garbage collector in .NET completely changes the rules here. In C#, reallocating memory in a loop is not always a bad idea.  In this scenario, for example, I may have been much better off leaving the original code alone.  The reason for this is the garbage collector.  The GC in .NET is incredibly effective, and leaving the allocation deep inside the call stack has some huge advantages.  First and foremost, it tends to make the code more maintainable – passing around object references tends to couple the methods together more than necessary, and overall increase the complexity of the code.  This is something that should be avoided unless there is a significant reason.  Second, (unlike C and C++) memory allocation of a single object in C# is normally cheap and fast.  Finally, and most critically, there is a large advantage to having short lived objects.  If you lift a variable out of the loop and reuse the memory, its much more likely that object will get promoted to Gen1 (or worse, Gen2).  This can cause expensive compaction operations to be required, and also lead to (at least temporary) memory fragmentation as well as more costly collections later. As such, I’ve found that it’s often (though not always) faster to leave memory allocations where you’d naturally place them – deep inside of the call graph, inside of the loops.  This causes the objects to stay very short lived, which in turn increases the efficiency of the garbage collector, and can dramatically improve the overall performance of the routine as a whole. In C#, I tend to: Keep variable declarations in the tightest scope possible Declare and allocate objects at usage While this tends to cause some of the same goals (reducing unnecessary allocations, etc), the goal here is a bit different – it’s about keeping the objects rooted for as little time as possible in order to (attempt) to keep them completely in Gen0, or worst case, Gen1.  It also has the huge advantage of keeping the code very maintainable – objects are used and “released” as soon as possible, which keeps the code very clean.  It does, however, often have the side effect of causing more allocations to occur, but keeping the objects rooted for a much shorter time. Now – nowhere here am I suggesting that these rules are hard, fast rules that are always true.  That being said, my time spent optimizing over the years encourages me to naturally write code that follows the above guidelines, then profile and adjust as necessary.  In my current project, however, I ran across one of those nasty little pitfalls that’s something to keep in mind – interop changes the rules. In this case, I was dealing with an API that, internally, used some COM objects.  In this case, these COM objects were leading to native allocations (most likely C++) occurring in a loop deep in my call graph.  Even though I was writing nice, clean managed code, the normal managed code rules for performance no longer apply.  After profiling to find the bottleneck in my code, I realized that my inner loop, a innocuous looking block of C# code, was effectively causing a set of native memory allocations in every iteration.  This required going back to a “native programming” mindset for optimization.  Lifting these variables and reusing them took a 1:10 routine down to 0:20 – again, a very worthwhile improvement. Overall, the lessons here are: Always profile if you suspect a performance problem – don’t assume any rule is correct, or any code is efficient just because it looks like it should be Remember to check memory allocations when profiling, not just CPU cycles Interop scenarios often cause managed code to act very differently than “normal” managed code. Native code can be hidden very cleverly inside of managed wrappers

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  • PostSharp, Obfuscation, and IL

    - by Simon Cooper
    Aspect-oriented programming (AOP) is a relatively new programming paradigm. Originating at Xerox PARC in 1994, the paradigm was first made available for general-purpose development as an extension to Java in 2001. From there, it has quickly been adapted for use in all the common languages used today. In the .NET world, one of the primary AOP toolkits is PostSharp. Attributes and AOP Normally, attributes in .NET are entirely a metadata construct. Apart from a few special attributes in the .NET framework, they have no effect whatsoever on how a class or method executes within the CLR. Only by using reflection at runtime can you access any attributes declared on a type or type member. PostSharp changes this. By declaring a custom attribute that derives from PostSharp.Aspects.Aspect, applying it to types and type members, and running the resulting assembly through the PostSharp postprocessor, you can essentially declare 'clever' attributes that change the behaviour of whatever the aspect has been applied to at runtime. A simple example of this is logging. By declaring a TraceAttribute that derives from OnMethodBoundaryAspect, you can automatically log when a method has been executed: public class TraceAttribute : PostSharp.Aspects.OnMethodBoundaryAspect { public override void OnEntry(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Entering {0}.{1}.", method.DeclaringType.FullName, method.Name)); } public override void OnExit(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Leaving {0}.{1}.", method.DeclaringType.FullName, method.Name)); } } [Trace] public void MethodToLog() { ... } Now, whenever MethodToLog is executed, the aspect will automatically log entry and exit, without having to add the logging code to MethodToLog itself. PostSharp Performance Now this does introduce a performance overhead - as you can see, the aspect allows access to the MethodBase of the method the aspect has been applied to. If you were limited to C#, you would be forced to retrieve each MethodBase instance using Type.GetMethod(), matching on the method name and signature. This is slow. Fortunately, PostSharp is not limited to C#. It can use any instruction available in IL. And in IL, you can do some very neat things. Ldtoken C# allows you to get the Type object corresponding to a specific type name using the typeof operator: Type t = typeof(Random); The C# compiler compiles this operator to the following IL: ldtoken [mscorlib]System.Random call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle( valuetype [mscorlib]System.RuntimeTypeHandle) The ldtoken instruction obtains a special handle to a type called a RuntimeTypeHandle, and from that, the Type object can be obtained using GetTypeFromHandle. These are both relatively fast operations - no string lookup is required, only direct assembly and CLR constructs are used. However, a little-known feature is that ldtoken is not just limited to types; it can also get information on methods and fields, encapsulated in a RuntimeMethodHandle or RuntimeFieldHandle: // get a MethodBase for String.EndsWith(string) ldtoken method instance bool [mscorlib]System.String::EndsWith(string) call class [mscorlib]System.Reflection.MethodBase [mscorlib]System.Reflection.MethodBase::GetMethodFromHandle( valuetype [mscorlib]System.RuntimeMethodHandle) // get a FieldInfo for the String.Empty field ldtoken field string [mscorlib]System.String::Empty call class [mscorlib]System.Reflection.FieldInfo [mscorlib]System.Reflection.FieldInfo::GetFieldFromHandle( valuetype [mscorlib]System.RuntimeFieldHandle) These usages of ldtoken aren't usable from C# or VB, and aren't likely to be added anytime soon (Eric Lippert's done a blog post on the possibility of adding infoof, methodof or fieldof operators to C#). However, PostSharp deals directly with IL, and so can use ldtoken to get MethodBase objects quickly and cheaply, without having to resort to string lookups. The kicker However, there are problems. Because ldtoken for methods or fields isn't accessible from C# or VB, it hasn't been as well-tested as ldtoken for types. This has resulted in various obscure bugs in most versions of the CLR when dealing with ldtoken and methods, and specifically, generic methods and methods of generic types. This means that PostSharp was behaving incorrectly, or just plain crashing, when aspects were applied to methods that were generic in some way. So, PostSharp has to work around this. Without using the metadata tokens directly, the only way to get the MethodBase of generic methods is to use reflection: Type.GetMethod(), passing in the method name as a string along with information on the signature. Now, this works fine. It's slower than using ldtoken directly, but it works, and this only has to be done for generic methods. Unfortunately, this poses problems when the assembly is obfuscated. PostSharp and Obfuscation When using ldtoken, obfuscators don't affect how PostSharp operates. Because the ldtoken instruction directly references the type, method or field within the assembly, it is unaffected if the name of the object is changed by an obfuscator. However, the indirect loading used for generic methods was breaking, because that uses the name of the method when the assembly is put through the PostSharp postprocessor to lookup the MethodBase at runtime. If the name then changes, PostSharp can't find it anymore, and the assembly breaks. So, PostSharp needs to know about any changes an obfuscator does to an assembly. The way PostSharp does this is by adding another layer of indirection. When PostSharp obfuscation support is enabled, it includes an extra 'name table' resource in the assembly, consisting of a series of method & type names. When PostSharp needs to lookup a method using reflection, instead of encoding the method name directly, it looks up the method name at a fixed offset inside that name table: MethodBase genericMethod = typeof(ContainingClass).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: get_Prop1 21: set_Prop1 22: DoFoo 23: GetWibble When the assembly is later processed by an obfuscator, the obfuscator can replace all the method and type names within the name table with their new name. That way, the reflection lookups performed by PostSharp will now use the new names, and everything will work as expected: MethodBase genericMethod = typeof(#kGy).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: #kkA 21: #zAb 22: #EF5a 23: #2tg As you can see, this requires direct support by an obfuscator in order to perform these rewrites. Dotfuscator supports it, and now, starting with SmartAssembly 6.6.4, SmartAssembly does too. So, a relatively simple solution to a tricky problem, with some CLR bugs thrown in for good measure. You don't see those every day!

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  • The Great Divorce

    - by BlackRabbitCoder
    I have a confession to make: I've been in an abusive relationship for more than 17 years now.  Yes, I am not ashamed to admit it, but I'm finally doing something about it. I met her in college, she was new and sexy and amazingly fast -- and I'd never met anything like her before.  Her style and her power captivated me and I couldn't wait to learn more about her.  I took a chance on her, and though I learned a lot from her -- and will always be grateful for my time with her -- I think it's time to move on. Her name was C++, and she so outshone my previous love, C, that any thoughts of going back evaporated in the heat of this new romance.  She promised me she'd be gentle and not hurt me the way C did.  She promised me she'd clean-up after herself better than C did.  She promised me she'd be less enigmatic and easier to keep happy than C was.  But I was deceived.  Oh sure, as far as truth goes, it wasn't a complete lie.  To some extent she was more fun, more powerful, safer, and easier to maintain.  But it just wasn't good enough -- or at least it's not good enough now. I loved C++, some part of me still does, it's my first-love of programming languages and I recognize its raw power, its blazing speed, and its improvements over its predecessor.  But with today's hardware, at speeds we could only dream to conceive of twenty years ago, that need for speed -- at the cost of all else -- has died, and that has left my feelings for C++ moribund. If I ever need to write an operating system or a device driver, then I might need that speed.  But 99% of the time I don't.  I'm a business-type programmer and chances are 90% of you are too, and even the ones who need speed at all costs may be surprised by how much you sacrifice for that.   That's not to say that I don't want my software to perform, and it's not to say that in the business world we don't care about speed or that our job is somehow less difficult or technical.  There's many times we write programs to handle millions of real-time updates or handle thousands of financial transactions or tracking trading algorithms where every second counts.  But if I choose to write my code in C++ purely for speed chances are I'll never notice the speed increase -- and equally true chances are it will be far more prone to crash and far less easy to maintain.  Nearly without fail, it's the macro-optimizations you need, not the micro-optimizations.  If I choose to write a O(n2) algorithm when I could have used a O(n) algorithm -- that can kill me.  If I choose to go to the database to load a piece of unchanging data every time instead of caching it on first load -- that too can kill me.  And if I cross the network multiple times for pieces of data instead of getting it all at once -- yes that can also kill me.  But choosing an overly powerful and dangerous mid-level language to squeeze out every last drop of performance will realistically not make stock orders process any faster, and more likely than not open up the system to more risk of crashes and resource leaks. And that's when my love for C++ began to die.  When I noticed that I didn't need that speed anymore.  That that speed was really kind of a lie.  Sure, I can be super efficient and pack bits in a byte instead of using separate boolean values.  Sure, I can use an unsigned char instead of an int.  But in the grand scheme of things it doesn't matter as much as you think it does.  The key is maintainability, and that's where C++ failed me.  I like to tell the other developers I work with that there's two levels of correctness in coding: Is it immediately correct? Will it stay correct? That is, you can hack together any piece of code and make it correct to satisfy a task at hand, but if a new developer can't come in tomorrow and make a fairly significant change to it without jeopardizing that correctness, it won't stay correct. Some people laugh at me when I say I now prefer maintainability over speed.  But that is exactly the point.  If you focus solely on speed you tend to produce code that is much harder to maintain over the long hall, and that's a load of technical debt most shops can't afford to carry and end up completely scrapping code before it's time.  When good code is written well for maintainability, though, it can be correct both now and in the future. And you know the best part is?  My new love is nearly as fast as C++, and in some cases even faster -- and better than that, I know C# will treat me right.  Her creators have poured hundreds of thousands of hours of time into making her the sexy beast she is today.  They made her easy to understand and not an enigmatic mess.  They made her consistent and not moody and amorphous.  And they made her perform as fast as I care to go by optimizing her both at compile time and a run-time. Her code is so elegant and easy on the eyes that I'm not worried where she will run to or what she'll pull behind my back.  She is powerful enough to handle all my tasks, fast enough to execute them with blazing speed, maintainable enough so that I can rely on even fairly new peers to modify my work, and rich enough to allow me to satisfy any need.  C# doesn't ask me to clean up her messes!  She cleans up after herself and she tries to make my life easier for me by taking on most of those optimization tasks C++ asked me to take upon myself.  Now, there are many of you who would say that I am the cause of my own grief, that it was my fault C++ didn't behave because I didn't pay enough attention to her.  That I alone caused the pain she inflicted on me.  And to some extent, you have a point.  But she was so high maintenance, requiring me to know every twist and turn of her vast and unrestrained power that any wrong term or bout of forgetfulness was met with painful reminders that she wasn't going to watch my back when I made a mistake.  But C#, she loves me when I'm good, and she loves me when I'm bad, and together we make beautiful code that is both fast and safe. So that's why I'm leaving C++ behind.  She says she's changing for me, but I have no interest in what C++0x may bring.  Oh, I'll still keep in touch, and maybe I'll see her now and again when she brings her problems to my door and asks for some attention -- for I always have a soft spot for her, you see.  But she's out of my house now.  I have three kids and a dog and a cat, and all require me to clean up after them, why should I have to clean up after my programming language as well?

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  • Tracing Silex from PHP to the OS with DTrace

    - by cj
    In this blog post I show the full stack tracing of Brendan Gregg's php_syscolors.d script in the DTrace Toolkit. The Toolkit contains a dozen very useful PHP DTrace scripts and many more scripts for other languages and the OS. For this example, I'll trace the PHP micro framework Silex, which was the topic of the second of two talks by Dustin Whittle at a recent SF PHP Meetup. His slides are at Silex: From Micro to Full Stack. Installing DTrace and PHP The php_syscolors.d script uses some static PHP probes and some kernel probes. For Oracle Linux I discussed installing DTrace and PHP in DTrace PHP Using Oracle Linux 'playground' Pre-Built Packages. On other platforms with DTrace support, follow your standard procedures to enable DTrace and load the correct providers. The sdt and systrace providers are required in addition to fasttrap. On Oracle Linux, I loaded the DTrace modules like: # modprobe fasttrap # modprobe sdt # modprobe systrace # chmod 666 /dev/dtrace/helper Installing the DTrace Toolkit I download DTraceToolkit-0.99.tar.gz and extracted it: $ tar -zxf DTraceToolkit-0.99.tar.gz The PHP scripts are in the Php directory and examples in the Examples directory. Installing Silex I downloaded the "fat" Silex .tgz file from the download page and extracted it: $ tar -zxf silex_fat.tgz I changed the demonstration silex/web/index.php so I could use the PHP development web server: <?php // web/index.php $filename = __DIR__.preg_replace('#(\?.*)$#', '', $_SERVER['REQUEST_URI']); if (php_sapi_name() === 'cli-server' && is_file($filename)) { return false; } require_once __DIR__.'/../vendor/autoload.php'; $app = new Silex\Application(); //$app['debug'] = true; $app->get('/hello', function() { return 'Hello!'; }); $app->run(); ?> Running DTrace The php_syscolors.d script uses the -Z option to dtrace, so it can be started before PHP, i.e. when there are zero of the requested probes available to be traced. I ran DTrace like: # cd DTraceToolkit-0.99/Php # ./php_syscolors.d Next, I started the PHP developer web server in a second terminal: $ cd silex $ php -S localhost:8080 -t web web/index.php At this point, the web server is idle, waiting for requests. DTrace is idle, waiting for the probes in php_syscolors.d to be fired, at which time the action associated with each probe will run. I then loaded the demonstration page in a browser: http://localhost:8080/hello When the request was fulfilled and the simple output of "Hello" was displayed, I ^C'd php and dtrace in their terminals to stop them. DTrace output over a thousand lines long had been generated. Here is one snippet from when run() was invoked: C PID/TID DELTA(us) FILE:LINE TYPE -- NAME ... 1 4765/4765 21 Application.php:487 func -> run 1 4765/4765 29 ClassLoader.php:182 func -> loadClass 1 4765/4765 17 ClassLoader.php:198 func -> findFile 1 4765/4765 31 ":- syscall -> access 1 4765/4765 26 ":- syscall <- access 1 4765/4765 16 ClassLoader.php:198 func <- findFile 1 4765/4765 25 ":- syscall -> newlstat 1 4765/4765 15 ":- syscall <- newlstat 1 4765/4765 13 ":- syscall -> newlstat 1 4765/4765 13 ":- syscall <- newlstat 1 4765/4765 22 ":- syscall -> newlstat 1 4765/4765 14 ":- syscall <- newlstat 1 4765/4765 15 ":- syscall -> newlstat 1 4765/4765 60 ":- syscall <- newlstat 1 4765/4765 13 ":- syscall -> newlstat 1 4765/4765 13 ":- syscall <- newlstat 1 4765/4765 20 ":- syscall -> open 1 4765/4765 16 ":- syscall <- open 1 4765/4765 26 ":- syscall -> newfstat 1 4765/4765 12 ":- syscall <- newfstat 1 4765/4765 17 ":- syscall -> newfstat 1 4765/4765 12 ":- syscall <- newfstat 1 4765/4765 12 ":- syscall -> newfstat 1 4765/4765 12 ":- syscall <- newfstat 1 4765/4765 20 ":- syscall -> mmap 1 4765/4765 14 ":- syscall <- mmap 1 4765/4765 3201 ":- syscall -> mmap 1 4765/4765 27 ":- syscall <- mmap 1 4765/4765 1233 ":- syscall -> munmap 1 4765/4765 53 ":- syscall <- munmap 1 4765/4765 15 ":- syscall -> close 1 4765/4765 13 ":- syscall <- close 1 4765/4765 34 Request.php:32 func -> main 1 4765/4765 22 Request.php:32 func <- main 1 4765/4765 31 ClassLoader.php:182 func <- loadClass 1 4765/4765 33 Request.php:249 func -> createFromGlobals 1 4765/4765 29 Request.php:198 func -> __construct 1 4765/4765 24 Request.php:218 func -> initialize 1 4765/4765 26 ClassLoader.php:182 func -> loadClass 1 4765/4765 89 ClassLoader.php:198 func -> findFile 1 4765/4765 43 ":- syscall -> access ... The output shows PHP functions being called and returning (and where they are located) and which system calls the PHP functions in turn invoked. The time each line took from the previous one is displayed in the third column. The first column is the CPU number. In this example, the process was always on CPU 1 so the output is naturally ordered without requiring post-processing, or the D script requiring to be modified to display a time stamp. On a terminal, the output of php_syscolors.d is color-coded according to whether each function is a PHP or system one, hence the file name. Summary With one tool, I was able to trace the interaction of a user application with the operating system. I was able to do this to an application running "live" in a web context. The DTrace Toolkit provides a very handy repository of DTrace information. Even though the PHP scripts were created in the time frame of the original PHP DTrace PECL extension, which only had PHP function entry and return probes, the scripts provide core examples for custom investigation and resolution scripts. You can easily adapt the ideas and and create scripts using the other PHP static probes, which are listed in the PHP Manual. Because DTrace is "always on", you can take advantage of it to resolve development questions or fix production situations.

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  • RIF PRD: Presentation syntax issues

    - by Charles Young
    Over Christmas I got to play a bit with the W3C RIF PRD and came across a few issues which I thought I would record for posterity. Specifically, I was working on a grammar for the presentation syntax using a GLR grammar parser tool (I was using the current CTP of ‘M’ (MGrammer) and Intellipad – I do so hope the MS guys don’t kill off M and Intellipad now they have dropped the other parts of SQL Server Modelling). I realise that the presentation syntax is non-normative and that any issues with it do not therefore compromise the standard. However, presentation syntax is useful in its own right, and it would be great to iron out any issues in a future revision of the standard. The main issues are actually not to do with the grammar at all, but rather with the ‘running example’ in the RIF PRD recommendation. I started with the code provided in Example 9.1. There are several discrepancies when compared with the EBNF rules documented in the standard. Broadly the problems can be categorised as follows: ·      Parenthesis mismatch – the wrong number of parentheses are used in various places. For example, in GoldRule, the RHS of the rule (the ‘Then’) is nested in the LHS (‘the If’). In NewCustomerAndWidgetRule, the RHS is orphaned from the LHS. Together with additional incorrect parenthesis, this leads to orphanage of UnknownStatusRule from the entire Document. ·      Invalid use of parenthesis in ‘Forall’ constructs. Parenthesis should not be used to enclose formulae. Removal of the invalid parenthesis gave me a feeling of inconsistency when comparing formulae in Forall to formulae in If. The use of parenthesis is not actually inconsistent in these two context, but in an If construct it ‘feels’ as if you are enclosing formulae in parenthesis in a LISP-like fashion. In reality, the parenthesis is simply being used to group subordinate syntax elements. The fact that an If construct can contain only a single formula as an immediate child adds to this feeling of inconsistency. ·      Invalid representation of compact URIs (CURIEs) in the context of Frame productions. In several places the URIs are not qualified with a namespace prefix (‘ex1:’). This conflicts with the definition of CURIEs in the RIF Datatypes and Built-Ins 1.0 document. Here are the productions: CURIE          ::= PNAME_LN                  | PNAME_NS PNAME_LN       ::= PNAME_NS PN_LOCAL PNAME_NS       ::= PN_PREFIX? ':' PN_LOCAL       ::= ( PN_CHARS_U | [0-9] ) ((PN_CHARS|'.')* PN_CHARS)? PN_CHARS       ::= PN_CHARS_U                  | '-' | [0-9] | #x00B7                  | [#x0300-#x036F] | [#x203F-#x2040] PN_CHARS_U     ::= PN_CHARS_BASE                  | '_' PN_CHARS_BASE ::= [A-Z] | [a-z] | [#x00C0-#x00D6] | [#x00D8-#x00F6]                  | [#x00F8-#x02FF] | [#x0370-#x037D] | [#x037F-#x1FFF]                  | [#x200C-#x200D] | [#x2070-#x218F] | [#x2C00-#x2FEF]                  | [#x3001-#xD7FF] | [#xF900-#xFDCF] | [#xFDF0-#xFFFD]                  | [#x10000-#xEFFFF] PN_PREFIX      ::= PN_CHARS_BASE ((PN_CHARS|'.')* PN_CHARS)? The more I look at CURIEs, the more my head hurts! The RIF specification allows prefixes and colons without local names, which surprised me. However, the CURIE Syntax 1.0 working group note specifically states that this form is supported…and then promptly provides a syntactic definition that seems to preclude it! However, on (much) deeper inspection, it appears that ‘ex1:’ (for example) is allowed, but would really represent a ‘fragment’ of the ‘reference’, rather than a prefix! Ouch! This is so completely ambiguous that it surely calls into question the whole CURIE specification.   In any case, RIF does not allow local names without a prefix. ·      Missing ‘External’ specifiers for built-in functions and predicates.  The EBNF specification enforces this for terms within frames, but does not appear to enforce (what I believe is) the correct use of External on built-in predicates. In any case, the running example only specifies ‘External’ once on the predicate in UnknownStatusRule. External() is required in several other places. ·      The List used on the LHS of UnknownStatusRule is comma-delimited. This is not supported by the EBNF definition. Similarly, the argument list of pred:list-contains is illegally comma-delimited. ·      Unnecessary use of conjunction around a single formula in DiscountRule. This is strictly legal in the EBNF, but redundant.   All the above issues concern the presentation syntax used in the running example. There are a few minor issues with the grammar itself. Note that Michael Kiefer stated in his paper “Rule Interchange Format: The Framework” that: “The presentation syntax of RIF … is an abstract syntax and, as such, it omits certain details that might be important for unambiguous parsing.” ·      The grammar cannot differentiate unambiguously between strategies and priorities on groups. A processor is forced to resolve this by detecting the use of IRIs and integers. This could easily be fixed in the grammar.   ·      The grammar cannot unambiguously parse the ‘->’ operator in frames. Specifically, ‘-’ characters are allowed in PN_LOCAL names and hence a parser cannot determine if ‘status->’ is (‘status’ ‘->’) or (‘status-’ ‘>’).   One way to fix this is to amend the PN_LOCAL production as follows: PN_LOCAL ::= ( PN_CHARS_U | [0-9] ) ((PN_CHARS|'.')* ((PN_CHARS)-('-')))? However, unilaterally changing the definition of this production, which is defined in the SPARQL Query Language for RDF specification, makes me uncomfortable. ·      I assume that the presentation syntax is case-sensitive. I couldn’t find this stated anywhere in the documentation, but function/predicate names do appear to be documented as being case-sensitive. ·      The EBNF does not specify whitespace handling. A couple of productions (RULE and ACTION_BLOCK) are crafted to enforce the use of whitespace. This is not necessary. It seems inconsistent with the rest of the specification and can cause parsing issues. In addition, the Const production exhibits whitespaces issues. The intention may have been to disallow the use of whitespace around ‘^^’, but any direct implementation of the EBNF will probably allow whitespace between ‘^^’ and the SYMSPACE. Of course, I am being a little nit-picking about all this. On the whole, the EBNF translated very smoothly and directly to ‘M’ (MGrammar) and proved to be fairly complete. I have encountered far worse issues when translating other EBNF specifications into usable grammars.   I can’t imagine there would be any difficulty in implementing the same grammar in Antlr, COCO/R, gppg, XText, Bison, etc. A general observation, which repeats a point made above, is that the use of parenthesis in the presentation syntax can feel inconsistent and un-intuitive.   It isn’t actually inconsistent, but I think the presentation syntax could be improved by adopting braces, rather than parenthesis, to delimit subordinate syntax elements in a similar way to so many programming languages. The familiarity of braces would communicate the structure of the syntax more clearly to people like me.  If braces were adopted, parentheses could be retained around ‘var (frame | ‘new()’) constructs in action blocks. This use of parenthesis feels very LISP-like, and I think that this is my issue. It’s as if the presentation syntax represents the deformed love-child of LISP and C. In some places (specifically, action blocks), parenthesis is used in a LISP-like fashion. In other places it is used like braces in C. I find this quite confusing. Here is a corrected version of the running example (Example 9.1) in compliant presentation syntax: Document(    Prefix( ex1 <http://example.com/2009/prd2> )    (* ex1:CheckoutRuleset *)  Group rif:forwardChaining (     (* ex1:GoldRule *)    Group 10 (      Forall ?customer such that And(?customer # ex1:Customer                                     ?customer[ex1:status->"Silver"])        (Forall ?shoppingCart such that ?customer[ex1:shoppingCart->?shoppingCart]           (If Exists ?value (And(?shoppingCart[ex1:value->?value]                                  External(pred:numeric-greater-than-or-equal(?value 2000))))            Then Do(Modify(?customer[ex1:status->"Gold"])))))      (* ex1:DiscountRule *)    Group (      Forall ?customer such that ?customer # ex1:Customer        (If Or( ?customer[ex1:status->"Silver"]                ?customer[ex1:status->"Gold"])         Then Do ((?s ?customer[ex1:shoppingCart-> ?s])                  (?v ?s[ex1:value->?v])                  Modify(?s [ex1:value->External(func:numeric-multiply (?v 0.95))]))))      (* ex1:NewCustomerAndWidgetRule *)    Group (      Forall ?customer such that And(?customer # ex1:Customer                                     ?customer[ex1:status->"New"] )        (If Exists ?shoppingCart ?item                   (And(?customer[ex1:shoppingCart->?shoppingCart]                        ?shoppingCart[ex1:containsItem->?item]                        ?item # ex1:Widget ) )         Then Do( (?s ?customer[ex1:shoppingCart->?s])                  (?val ?s[ex1:value->?val])                  (?voucher ?customer[ex1:voucher->?voucher])                  Retract(?customer[ex1:voucher->?voucher])                  Retract(?voucher)                  Modify(?s[ex1:value->External(func:numeric-multiply(?val 0.90))]))))      (* ex1:UnknownStatusRule *)    Group (      Forall ?customer such that ?customer # ex1:Customer        (If Not(Exists ?status                       (And(?customer[ex1:status->?status]                            External(pred:list-contains(List("New" "Bronze" "Silver" "Gold") ?status)) )))         Then Do( Execute(act:print(External(func:concat("New customer: " ?customer))))                  Assert(?customer[ex1:status->"New"]))))  ) )   I hope that helps someone out there :-)

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  • Refactoring Part 1 : Intuitive Investments

    - by Wes McClure
    Fear, it’s what turns maintaining applications into a nightmare.  Technology moves on, teams move on, someone is left to operate the application, what was green is now perceived brown.  Eventually the business will evolve and changes will need to be made.  The approach to those changes often dictates the long term viability of the application.  Fear of change, lack of passion and a lack of interest in understanding the domain often leads to a paranoia to do anything that doesn’t involve duct tape and bailing twine.  Don’t get me wrong, those have a place in the short term viability of a project but they don’t have a place in the long term.  Add to it “us versus them” in regards to the original team and those that maintain it, internal politics and other factors and you have a recipe for disaster.  This results in code that quickly becomes unmanageable.  Even the most clever of designs will eventually become sub optimal and debt will amount that exponentially makes changes difficult.  This is where refactoring comes in, and it’s something I’m very passionate about.  Refactoring is about improving the process whereby we make change, it’s an exponential investment in the process of change. Without it we will incur exponential complexity that halts productivity. Investments, especially in the long term, require intuition and reflection.  How can we tackle new development effectively via evolving the original design and paying off debt that has been incurred? The longer we wait to ask and answer this question, the more it will cost us.  Small requests don’t warrant big changes, but realizing when changes now will pay off in the long term, and especially in the short term, is valuable. I have done my fair share of maintaining applications and continuously refactoring as needed, but recently I’ve begun work on a project that hasn’t had much debt, if any, paid down in years.  This is the first in a series of blog posts to try to capture the process which is largely driven by intuition of smaller refactorings from other projects. Signs that refactoring could help: Testability How can decreasing test time not pay dividends? One of the first things I found was that a very important piece often takes 30+ minutes to test.  I can only imagine how much time this has cost historically, but more importantly the time it might cost in the coming weeks: I estimate at least 10-20 hours per person!  This is simply unacceptable for almost any situation.  As it turns out, about 6 hours of working with this part of the application and I was able to cut the time down to under 30 seconds!  In less than the lost time of one week, I was able to fix the problem for all future weeks! If we can’t test fast then we can’t change fast, nor with confidence. Code is used by end users and it’s also used by developers, consider your own needs in terms of the code base.  Adding logic to enable/disable features during testing can help decouple parts of an application and lead to massive improvements.  What exactly is so wrong about test code in real code?  Often, these become features for operators and sometimes end users.  If you cannot run an integration test within a test runner in your IDE, it’s time to refactor. Readability Are variables named meaningfully via a ubiquitous language? Is the code segmented functionally or behaviorally so as to minimize the complexity of any one area? Are aspects properly segmented to avoid confusion (security, logging, transactions, translations, dependency management etc) Is the code declarative (what) or imperative (how)?  What matters, not how.  LINQ is a great abstraction of the what, not how, of collection manipulation.  The Reactive framework is a great example of the what, not how, of managing streams of data. Are constants abstracted and named, or are they just inline? Do people constantly bitch about the code/design? If the code is hard to understand, it will be hard to change with confidence.  It’s a large undertaking if the original designers didn’t pay much attention to readability and as such will never be done to “completion.”  Make sure not to go over board, instead use this as you change an application, not in lieu of changes (like with testability). Complexity Simplicity will never be achieved, it’s highly subjective.  That said, a lot of code can be significantly simplified, tidy it up as you go.  Refactoring will often converge upon a simplification step after enough time, keep an eye out for this. Understandability In the process of changing code, one often gains a better understanding of it.  Refactoring code is a good way to learn how it works.  However, it’s usually best in combination with other reasons, in effect killing two birds with one stone.  Often this is done when readability is poor, in which case understandability is usually poor as well.  In the large undertaking we are making with this legacy application, we will be replacing it.  Therefore, understanding all of its features is important and this refactoring technique will come in very handy. Unused code How can deleting things not help? This is a freebie in refactoring, it’s very easy to detect with modern tools, especially in statically typed languages.  We have VCS for a reason, if in doubt, delete it out (ok that was cheesy)! If you don’t know where to start when refactoring, this is an excellent starting point! Duplication Do not pray and sacrifice to the anti-duplication gods, there are excellent examples where consolidated code is a horrible idea, usually with divergent domains.  That said, mediocre developers live by copy/paste.  Other times features converge and aren’t combined.  Tools for finding similar code are great in the example of copy/paste problems.  Knowledge of the domain helps identify convergent concepts that often lead to convergent solutions and will give intuition for where to look for conceptual repetition. 80/20 and the Boy Scouts It’s often said that 80% of the time 20% of the application is used most.  These tend to be the parts that are changed.  There are also parts of the code where 80% of the time is spent changing 20% (probably for all the refactoring smells above).  I focus on these areas any time I make a change and follow the philosophy of the Boy Scout in cleaning up more than I messed up.  If I spend 2 hours changing an application, in the 20%, I’ll always spend at least 15 minutes cleaning it or nearby areas. This gives a huge productivity edge on developers that don’t. Ironically after a short period of time the 20% shrinks enough that we don’t have to spend 80% of our time there and can move on to other areas.   Refactoring is highly subjective, never attempt to refactor to completion!  Learn to be comfortable with leaving one part of the application in a better state than others.  It’s an evolution, not a revolution.  These are some simple areas to look into when making changes and can help get one started in the process.  I’ve often found that refactoring is a convergent process towards simplicity that sometimes spans a few hours but often can lead to massive simplifications over the timespan of weeks and months of regular development.

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