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• How To Activate Your Free Office 2007 to 2010 Tech Guarantee Upgrade

  - by Matthew Guay

  Have you purchased Office 2007 since March 5th, 2010?  If so, here’s how you can activate and download your free upgrade to Office 2010! Microsoft Office 2010 has just been released, and today you can purchase upgrades from most retail stores or directly from Microsoft via download.  But if you’ve purchased a new copy of Office 2007 or a new computer that came with Office 2007 since March 5th, 2010, then you’re entitled to an absolutely free upgrade to Office 2010.  You’ll need enter information about your Office 2007 and then download the upgrade, so we’ll step you through the process. Getting Started First, if you’ve recently purchased Office 2007 but haven’t installed it, you’ll need to go ahead and install it before you can get your free Office 2010 upgrade.  Install it as normal.   Once Office 2007 is installed, run any of the Office programs.  You’ll be prompted to activate Office.  Make sure you’re connected to the internet, and then click Next to activate. Get your Free Upgrade to Office 2010 Now you’re ready to download your upgrade to Office 2010.  Head to the Office Tech Guarantee site (link below), and click Upgrade now. You’ll need to enter some information about your Office 2007.  Check that you purchased your copy of Office 2007 after March 5th, select your computer manufacturer, and check that you agree to the terms. Now you’re going to need the Product ID number from Office 2007.  To find this, open Word or any other Office 2007 application.  Click the Office Orb, and select Options on the bottom. Select the Resources button on the left, and then click About. Near the bottom of this dialog, you’ll see your Product ID.  This should be a number like: 12345-123-1234567-12345   Go back to the Office Tech Guarantee signup page in your browser, and enter this Product ID.  Select the language of your edition of Office 2007, enter the verification code, and then click Submit. It may take a few moments to validate your Product ID. When it is finished, you’ll be taken to an order page that shows the edition of Office 2010 you’re eligible to receive.  The upgrade download is free, but if you’d like to purchase a backup DVD of Office 2010, you can add it to your order for $13.99.  Otherwise, simply click Continue to accept. Do note that the edition of Office 2010 you receive may be different that the edition of Office 2007 you purchased, as the number of editions has been streamlined in the Office 2010 release.  Here’s a chart you can check to see what edition you’ll receive.  Note that you’ll still be allowed to install Office on the same number of computers; for example, Office 2007 Home and Student allows you to install it on up to 3 computers in the same house, and your Office 2010 upgrade will allow the same. Office 2007 Edition Office 2010 Upgrade You’ll Receive Office 2007 Home and Student Office Home and Student 2010 Office Basic 2007Office Standard 2007 Office Home and Business 2010 Office Small Business 2007Office Professional 2007Office Ultimate 2007 Office Professional 2010 Office Professional 2007 AcademicOffice Ultimate 2007 Academic Office Professional Academic 2010 Sign in with your Windows Live ID, or create a new one if you don’t already have one. Enter your name, select your country, and click Create My Account.  Note that Office will send Office 2010 tips to your email address; if you don’t wish to receive them, you can unsubscribe from the emails later.   Finally, you’re ready to download Office 2010!  Click the Download Now link to start downloading Office 2010.  Your Product Key will appear directly above the Download link, so you can copy it and then paste it in the installer when your download is finished.  You will additionally receive an email with the download links and product key, so if your download fails you can always restart it from that link. If your edition of Office 2007 included the Office Business Contact Manager, you will be able to download it from the second Download link.  And, of course, even if you didn’t order a backup DVD, you can always burn the installers to a DVD for a backup.   Install Office 2010 Once you’re finished downloading Office 2010, run the installer to get it installed on your computer.  Enter your Product Key from the Tech Guarantee website as above, and click Continue. Accept the license agreement, and then click Upgrade to upgrade to the latest version of Office.   The installer will remove all of your Office 2007 applications, and then install their 2010 counterparts.  If you wish to keep some of your Office 2007 applications instead, click Customize and then select to either keep all previous versions or simply keep specific applications. By default, Office 2010 will try to activate online automatically.  If it doesn’t activate during the install, you’ll need to activate it when you first run any of the Office 2010 apps.   Conclusion The Tech Guarantee makes it easy to get the latest version of Office if you recently purchased Office 2007.  The Tech Guarantee program is open through the end of September, so make sure to grab your upgrade during this time.  Actually, if you find a great deal on Office 2007 from a major retailer between now and then, you could also take advantage of this program to get Office 2010 cheaper. And if you need help getting started with Office 2010, check out our articles that can help you get situated in your new version of Office! Link Activate and Download Your free Office 2010 Tech Guarantee Upgrade Similar Articles Productive Geek Tips Remove Office 2010 Beta and Reinstall Office 2007Upgrade Office 2003 to 2010 on XP or Run them Side by SideCenter Pictures and Other Objects in Office 2007 & 2010Change the Default Color Scheme in Office 2010Show Two Time Zones in Your Outlook 2007 Calendar 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 HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Windows Media Player Plus! – Cool WMP Enhancer Get Your Team’s World Cup Schedule In Google Calendar Backup Drivers With Driver Magician TubeSort: YouTube Playlist Organizer XPS file format & XPS Viewer Explained Microsoft Office Web Apps Guide

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• I have finally traded my Blackberry in for a Droid!

  - by Bob Porter

  Over the years I have used a number of different types of phones. Windows Mobile, Blackberry, Nokia, and now Android. Until the Blackberry, which was my last phone (and I still have one issued from my office) I had never found a phone that “just worked” especially with email and messaging. The Blackberry did, and does, excel at those functions. My last personal phone was a Storm 1 which was Blackberry’s first touch screen phone. The Storm 2 was an improved version that fixed some screen press detection issues from the first model and it added Wifi. Over the last few years I have watched others acquire and fall in love with their ‘Droid’s including a number of iPhone users which surprised me. Our office has until recently only supported Blackberry phones, adding iPhones within the last year or so. When I spoke with our internal telecom folks they confirmed they were evaluating Android phones, but felt they still were not secure enough out of the box for corporate use and SOX compliance. That being said, as a personal phone, the Droid Rocks! I am impressed with its speed, the number of apps available, and the overall design. It is not as “flashy” as an iPhone but it does everything that I care about and more. The model I bought is the Motorola Droid 2 Global from Verizon. It is currently running Android 2.2 for it’s OS, 2.3 is just around the corner. It has 8 gigs of internal flash memory and can handle up to a 32 gig SDCard. (I currently have 2 8 gig cards, one for backups, and have ordered a 16 gig card!) Being a geek at heart, I “rooted” the phone which means gained superuser access to the OS on the phone. And opens a number of doors for further modifications down the road. Also being a geek meant I have already setup a development environment and built and deployed the obligatory “Hello Droid” application. I will be writing of my development experiences with this new platform here often, to start off I thought I would share my current application list to give you an idea what I am using. Zedge: http://market.android.com/details?id=net.zedge.android XDA: http://market.android.com/details?id=com.quoord.tapatalkxda.activity WRAL.com: http://market.android.com/details?id=com.mylocaltv.wral Wireless Tether: http://market.android.com/details?id=android.tether Winamp: http://market.android.com/details?id=com.nullsoft.winamp Win7 Clock: http://market.android.com/details?id=com.androidapps.widget.toggles.win7 Wifi Analyzer: http://market.android.com/details?id=com.farproc.wifi.analyzer WeatherBug: http://market.android.com/details?id=com.aws.android Weather Widget Forecast Addon: http://market.android.com/details?id=com.androidapps.weather.forecastaddon Weather & Toggle Widgets: http://market.android.com/details?id=com.androidapps.widget.weather2 Vlingo: http://market.android.com/details?id=com.vlingo.client VirtualTENHO-G: http://market.android.com/details?id=jp.bustercurry.virtualtenho_g Twitter: http://market.android.com/details?id=com.twitter.android TweetDeck: http://market.android.com/details?id=com.thedeck.android.app Tricorder: http://market.android.com/details?id=org.hermit.tricorder Titanium Backup PRO: http://market.android.com/details?id=com.keramidas.TitaniumBackupPro Titanium Backup: http://market.android.com/details?id=com.keramidas.TitaniumBackup Terminal Emulator: http://market.android.com/details?id=jackpal.androidterm Talking Tom Free: http://market.android.com/details?id=com.outfit7.talkingtom Stock Blue: http://market.android.com/details?id=org.adw.theme.stockblue ST: Red Alert Free: http://market.android.com/details?id=com.oldplanets.redalertwallpaper ST: Red Alert: http://market.android.com/details?id=com.oldplanets.redalertwallpaperplus Solitaire: http://market.android.com/details?id=com.kmagic.solitaire Skype: http://market.android.com/details?id=com.skype.raider Silent Time Lite: http://market.android.com/details?id=com.QuiteHypnotic.SilentTime ShopSavvy: http://market.android.com/details?id=com.biggu.shopsavvy Shopper: http://market.android.com/details?id=com.google.android.apps.shopper Shiny clock: http://market.android.com/details?id=com.androidapps.clock.shiny ShareMyApps: http://market.android.com/details?id=com.mattlary.shareMyApps Sense Glass ADW Theme: http://market.android.com/details?id=com.dtanquary.senseglassadwtheme ROM Manager: http://market.android.com/details?id=com.koushikdutta.rommanager Roboform Bookmarklet Installer: http://market.android.com/details?id=roboformBookmarkletInstaller.android.com RealCalc: http://market.android.com/details?id=uk.co.nickfines.RealCalc Package Buddy: http://market.android.com/details?id=com.psyrus.packagebuddy Overstock: http://market.android.com/details?id=com.overstock OMGPOP Toggle: http://market.android.com/details?id=com.androidapps.widget.toggle.omgpop OI File Manager: http://market.android.com/details?id=org.openintents.filemanager nook: http://market.android.com/details?id=bn.ereader MyAtlas-Google Maps Navigation ext: http://market.android.com/details?id=com.adaptdroid.navbookfree3 MSN Droid: http://market.android.com/details?id=msn.droid.im Matrix Live Wallpaper: http://market.android.com/details?id=com.jarodyv.livewallpaper.matrix LogMeIn: http://market.android.com/details?id=com.logmein.ignitionpro.android Liveshare: http://market.android.com/details?id=com.cooliris.app.liveshare Kobo: http://market.android.com/details?id=com.kobobooks.android Instant Heart Rate: http://market.android.com/details?id=si.modula.android.instantheartrate IMDb: http://market.android.com/details?id=com.imdb.mobile Home Plus Weather: http://market.android.com/details?id=com.androidapps.widget.skin.weather.homeplus Handcent SMS: http://market.android.com/details?id=com.handcent.nextsms H7C Clock: http://market.android.com/details?id=com.androidapps.widget.clock.skin.h7c GTasks: http://market.android.com/details?id=org.dayup.gtask GPS Status: http://market.android.com/details?id=com.eclipsim.gpsstatus2 Google Voice: http://market.android.com/details?id=com.google.android.apps.googlevoice Google Sky Map: http://market.android.com/details?id=com.google.android.stardroid Google Reader: http://market.android.com/details?id=com.google.android.apps.reader GoMarks: http://market.android.com/details?id=com.androappsdev.gomarks Goggles: http://market.android.com/details?id=com.google.android.apps.unveil Glossy Black Weather: http://market.android.com/details?id=com.androidapps.widget.weather.skin.glossyblack Fox News: http://market.android.com/details?id=com.foxnews.android Foursquare: http://market.android.com/details?id=com.joelapenna.foursquared FBReader: http://market.android.com/details?id=org.geometerplus.zlibrary.ui.android Fandango: http://market.android.com/details?id=com.fandango Facebook: http://market.android.com/details?id=com.facebook.katana Extensive Notes Pro: http://market.android.com/details?id=com.flufflydelusions.app.extensive_notes_donate Expense Manager: http://market.android.com/details?id=com.expensemanager Espresso UI (LightShow w/ Slide): http://market.android.com/details?id=com.jaguirre.slide.lightshow Engadget: http://market.android.com/details?id=com.aol.mobile.engadget Earth: http://market.android.com/details?id=com.google.earth Drudge: http://market.android.com/details?id=com.iavian.dreport Dropbox: http://market.android.com/details?id=com.dropbox.android DroidForums: http://market.android.com/details?id=com.quoord.tapatalkdrodiforums.activity DroidArmor ADW: http://market.android.com/details?id=mobi.addesigns.droidarmorADW Droid Weather Icons: http://market.android.com/details?id=com.androidapps.widget.weather.skins.white Droid 2 Bootstrapper: http://market.android.com/details?id=com.koushikdutta.droid2.bootstrap doubleTwist: http://market.android.com/details?id=com.doubleTwist.androidPlayer Documents To Go: http://market.android.com/details?id=com.dataviz.docstogo Digital Clock Widget: http://market.android.com/details?id=com.maize.digitalClock Desk Home: http://market.android.com/details?id=com.cowbellsoftware.deskdock Default Clock: http://market.android.com/details?id=com.androidapps.widget.clock.skins.defaultclock Daily Expense Manager: http://market.android.com/details?id=com.techahead.ExpenseManager ConnectBot: http://market.android.com/details?id=org.connectbot Colorized Weather Icons: http://market.android.com/details?id=com.androidapps.widget.weather.colorized Chrome to Phone: http://market.android.com/details?id=com.google.android.apps.chrometophone CardStar: http://market.android.com/details?id=com.cardstar.android Books: http://market.android.com/details?id=com.google.android.apps.books Black Ipad Toggle: http://market.android.com/details?id=com.androidapps.toggle.widget.skin.blackipad Black Glass ADW Theme: http://market.android.com/details?id=com.dtanquary.blackglassadwtheme Bing: http://market.android.com/details?id=com.microsoft.mobileexperiences.bing BeyondPod Unlock Key: http://market.android.com/details?id=mobi.beyondpod.unlockkey BeyondPod: http://market.android.com/details?id=mobi.beyondpod BeejiveIM: http://market.android.com/details?id=com.beejive.im Beautiful Widgets Animations Addon: http://market.android.com/details?id=com.levelup.bw.forecast Beautiful Widgets: http://market.android.com/details?id=com.levelup.beautifulwidgets Beautiful Live Weather: http://market.android.com/details?id=com.levelup.beautifullive BBC News: http://market.android.com/details?id=net.jimblackler.newswidget Barnacle Wifi Tether: http://market.android.com/details?id=net.szym.barnacle Barcode Scanner: http://market.android.com/details?id=com.google.zxing.client.android ASTRO SMB Module: http://market.android.com/details?id=com.metago.astro.smb ASTRO Pro: http://market.android.com/details?id=com.metago.astro.pro ASTRO Bluetooth Module: http://market.android.com/details?id=com.metago.astro.network.bluetooth ASTRO: http://market.android.com/details?id=com.metago.astro AppBrain App Market: http://market.android.com/details?id=com.appspot.swisscodemonkeys.apps App Drawer Icon Pack: http://market.android.com/details?id=com.adwtheme.appdrawericonpack androidVNC: http://market.android.com/details?id=android.androidVNC AndroidGuys: http://market.android.com/details?id=com.handmark.mpp.AndroidGuys Android System Info: http://market.android.com/details?id=com.electricsheep.asi AndFTP: http://market.android.com/details?id=lysesoft.andftp ADWTheme Red: http://market.android.com/details?id=adw.theme.red ADWLauncher EX: http://market.android.com/details?id=org.adwfreak.launcher ADW.Theme.One: http://market.android.com/details?id=org.adw.theme.one ADW.Faded theme: http://market.android.com/details?id=com.xrcore.adwtheme.faded ADW Gingerbread: http://market.android.com/details?id=me.robertburns.android.adwtheme.gingerbread Advanced Task Killer Free: http://market.android.com/details?id=com.rechild.advancedtaskkiller Adobe Reader: http://market.android.com/details?id=com.adobe.reader Adobe Flash Player 10.1: http://market.android.com/details?id=com.adobe.flashplayer Adobe AIR: http://market.android.com/details?id=com.adobe.air 3G Auto OnOff: http://market.android.com/details?id=com.yuantuo --- Generated by ShareMyApps http://market.android.com/details?id=com.mattlary.shareMyApps Sent from my Droid

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• C# 4: The Curious ConcurrentDictionary

  - by James Michael Hare

  In my previous post (here) I did a comparison of the new ConcurrentQueue versus the old standard of a System.Collections.Generic Queue with simple locking.  The results were exactly what I would have hoped, that the ConcurrentQueue was faster with multi-threading for most all situations.  In addition, concurrent collections have the added benefit that you can enumerate them even if they're being modified. So I set out to see what the improvements would be for the ConcurrentDictionary, would it have the same performance benefits as the ConcurrentQueue did?  Well, after running some tests and multiple tweaks and tunes, I have good and bad news. But first, let's look at the tests.  Obviously there's many things we can do with a dictionary.  One of the most notable uses, of course, in a multi-threaded environment is for a small, local in-memory cache.  So I set about to do a very simple simulation of a cache where I would create a test class that I'll just call an Accessor.  This accessor will attempt to look up a key in the dictionary, and if the key exists, it stops (i.e. a cache "hit").  However, if the lookup fails, it will then try to add the key and value to the dictionary (i.e. a cache "miss").  So here's the Accessor that will run the tests: 1: internal class Accessor 2: { 3: public int Hits { get; set; } 4: public int Misses { get; set; } 5: public Func<int, string> GetDelegate { get; set; } 6: public Action<int, string> AddDelegate { get; set; } 7: public int Iterations { get; set; } 8: public int MaxRange { get; set; } 9: public int Seed { get; set; } 10:  11: public void Access() 12: { 13: var randomGenerator = new Random(Seed); 14:  15: for (int i=0; i<Iterations; i++) 16: { 17: // give a wide spread so will have some duplicates and some unique 18: var target = randomGenerator.Next(1, MaxRange); 19:  20: // attempt to grab the item from the cache 21: var result = GetDelegate(target); 22:  23: // if the item doesn't exist, add it 24: if(result == null) 25: { 26: AddDelegate(target, target.ToString()); 27: Misses++; 28: } 29: else 30: { 31: Hits++; 32: } 33: } 34: } 35: } Note that so I could test different implementations, I defined a GetDelegate and AddDelegate that will call the appropriate dictionary methods to add or retrieve items in the cache using various techniques. So let's examine the three techniques I decided to test: Dictionary with mutex - Just your standard generic Dictionary with a simple lock construct on an internal object. Dictionary with ReaderWriterLockSlim - Same Dictionary, but now using a lock designed to let multiple readers access simultaneously and then locked when a writer needs access. ConcurrentDictionary - The new ConcurrentDictionary from System.Collections.Concurrent that is supposed to be optimized to allow multiple threads to access safely. So the approach to each of these is also fairly straight-forward.  Let's look at the GetDelegate and AddDelegate implementations for the Dictionary with mutex lock: 1: var addDelegate = (key,val) => 2: { 3: lock (_mutex) 4: { 5: _dictionary[key] = val; 6: } 7: }; 8: var getDelegate = (key) => 9: { 10: lock (_mutex) 11: { 12: string val; 13: return _dictionary.TryGetValue(key, out val) ? val : null; 14: } 15: }; Nothing new or fancy here, just your basic lock on a private object and then query/insert into the Dictionary. Now, for the Dictionary with ReadWriteLockSlim it's a little more complex: 1: var addDelegate = (key,val) => 2: { 3: _readerWriterLock.EnterWriteLock(); 4: _dictionary[key] = val; 5: _readerWriterLock.ExitWriteLock(); 6: }; 7: var getDelegate = (key) => 8: { 9: string val; 10: _readerWriterLock.EnterReadLock(); 11: if(!_dictionary.TryGetValue(key, out val)) 12: { 13: val = null; 14: } 15: _readerWriterLock.ExitReadLock(); 16: return val; 17: }; And finally, the ConcurrentDictionary, which since it does all it's own concurrency control, is remarkably elegant and simple: 1: var addDelegate = (key,val) => 2: { 3: _concurrentDictionary[key] = val; 4: }; 5: var getDelegate = (key) => 6: { 7: string s; 8: return _concurrentDictionary.TryGetValue(key, out s) ? s : null; 9: };                    Then, I set up a test harness that would simply ask the user for the number of concurrent Accessors to attempt to Access the cache (as specified in Accessor.Access() above) and then let them fly and see how long it took them all to complete.  Each of these tests was run with 10,000,000 cache accesses divided among the available Accessor instances.  All times are in milliseconds. 1: Dictionary with Mutex Locking 2: --------------------------------------------------- 3: Accessors Mostly Misses Mostly Hits 4: 1 7916 3285 5: 10 8293 3481 6: 100 8799 3532 7: 1000 8815 3584 8:  9:  10: Dictionary with ReaderWriterLockSlim Locking 11: --------------------------------------------------- 12: Accessors Mostly Misses Mostly Hits 13: 1 8445 3624 14: 10 11002 4119 15: 100 11076 3992 16: 1000 14794 4861 17:  18:  19: Concurrent Dictionary 20: --------------------------------------------------- 21: Accessors Mostly Misses Mostly Hits 22: 1 17443 3726 23: 10 14181 1897 24: 100 15141 1994 25: 1000 17209 2128 The first test I did across the board is the Mostly Misses category.  The mostly misses (more adds because data requested was not in the dictionary) shows an interesting trend.  In both cases the Dictionary with the simple mutex lock is much faster, and the ConcurrentDictionary is the slowest solution.  But this got me thinking, and a little research seemed to confirm it, maybe the ConcurrentDictionary is more optimized to concurrent "gets" than "adds".  So since the ratio of misses to hits were 2 to 1, I decided to reverse that and see the results. So I tweaked the data so that the number of keys were much smaller than the number of iterations to give me about a 2 to 1 ration of hits to misses (twice as likely to already find the item in the cache than to need to add it).  And yes, indeed here we see that the ConcurrentDictionary is indeed faster than the standard Dictionary here.  I have a strong feeling that as the ration of hits-to-misses gets higher and higher these number gets even better as well.  This makes sense since the ConcurrentDictionary is read-optimized. Also note that I tried the tests with capacity and concurrency hints on the ConcurrentDictionary but saw very little improvement, I think this is largely because on the 10,000,000 hit test it quickly ramped up to the correct capacity and concurrency and thus the impact was limited to the first few milliseconds of the run. So what does this tell us?  Well, as in all things, ConcurrentDictionary is not a panacea.  It won't solve all your woes and it shouldn't be the only Dictionary you ever use.  So when should we use each? Use System.Collections.Generic.Dictionary when: You need a single-threaded Dictionary (no locking needed). You need a multi-threaded Dictionary that is loaded only once at creation and never modified (no locking needed). You need a multi-threaded Dictionary to store items where writes are far more prevalent than reads (locking needed). And use System.Collections.Concurrent.ConcurrentDictionary when: You need a multi-threaded Dictionary where the writes are far more prevalent than reads. You need to be able to iterate over the collection without locking it even if its being modified. Both Dictionaries have their strong suits, I have a feeling this is just one where you need to know from design what you hope to use it for and make your decision based on that criteria.

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• AutoMapper MappingFunction from Source Type of NameValueCollection

  - by REA_ANDREW

  I have had a situation arise today where I need to construct a complex type from a source of a NameValueCollection.  A little while back I submitted a patch for the Agatha Project to include REST (JSON and XML) support for the service contract.  I realized today that as useful as it is, it did not actually support true REST conformance, as REST should support GET so that you can use JSONP from JavaScript directly meaning you can query cross domain services.  My original implementation for POX and JSON used the POST method and this immediately rules out JSONP as from reading, JSONP only works with GET Requests. This then raised another issue.  The current operation contract of Agatha and one of its main benefits is that you can supply an array of Request objects in a single request, limiting the about of server requests you need to make.  Now, at the present time I am thinking that this will not be the case for the REST imlementation but will yield the benefits of the fact that : The same Request objects can be used for SOAP and RST (POX, JSON) The construct of the JavaScript functions will be simpler and more readable It will enable the use of JSONP for cross domain REST Services The current contract for the Agatha WcfRequestProcessor is at time of writing the following: [ServiceContract] public interface IWcfRequestProcessor { [OperationContract(Name = "ProcessRequests")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] Response[] Process(params Request[] requests); [OperationContract(Name = "ProcessOneWayRequests", IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] void ProcessOneWayRequests(params OneWayRequest[] requests); }   My current proposed solution, and at the very early stages of my concept is as follows: [ServiceContract] public interface IWcfRestJsonRequestProcessor { [OperationContract(Name="process")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] [WebGet(UriTemplate = "process/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] Response[] Process(string name, NameValueCollection parameters); [OperationContract(Name="processoneway",IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [WebGet(UriTemplate = "process-one-way/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] void ProcessOneWayRequests(string name, NameValueCollection parameters); }   Now this part I have not yet implemented, it is the preliminart step which I have developed which will allow me to take the name of the Request Type and the NameValueCollection and construct the complex type which is that of the Request which I can then supply to a nested instance of the original IWcfRequestProcessor  and work as it should normally.  To give an example of some of the urls which you I envisage with this method are: http://www.url.com/service.svc/json/process/getweather/?location=london http://www.url.com/service.svc/json/process/getproductsbycategory/?categoryid=1 http://www.url.om/service.svc/json/process/sayhello/?name=andy Another reason why my direction has gone to a single request for the REST implementation is because of restrictions which are imposed by browsers on the length of the url.  From what I have read this is on average 2000 characters.  I think that this is a very acceptable usage limit in the context of using 1 request, but I do not think this is acceptable for accommodating multiple requests chained together.  I would love to be corrected on that one, I really would but unfortunately from what I have read I have come to the conclusion that this is not the case. The mapping function So, as I say this is just the first pass I have made at this, and I am not overly happy with the try catch for detecting types without default constructors.  I know there is a better way but for the minute, it escapes me.  I would also like to know the correct way for adding mapping functions and not using the anonymous way that I have used.  To achieve this I have used recursion which I am sure is what other mapping function use. As you do have to go as deep as the complex type is. public static object RecurseType(NameValueCollection collection, Type type, string prefix) { try { var returnObject = Activator.CreateInstance(type); foreach (var property in type.GetProperties()) { foreach (var key in collection.AllKeys) { if (String.IsNullOrEmpty(prefix) || key.Length > prefix.Length) { var propertyNameToMatch = String.IsNullOrEmpty(prefix) ? key : key.Substring(property.Name.IndexOf(prefix) + prefix.Length + 1); if (property.Name == propertyNameToMatch) { property.SetValue(returnObject, Convert.ChangeType(collection.Get(key), property.PropertyType), null); } else if(property.GetValue(returnObject,null) == null) { property.SetValue(returnObject, RecurseType(collection, property.PropertyType, String.Concat(prefix, property.PropertyType.Name)), null); } } } } return returnObject; } catch (MissingMethodException) { //Quite a blunt way of dealing with Types without default constructor return null; } }   Another thing is performance, I have not measured this in anyway, it is as I say the first pass, so I hope this can be the start of a more perfected implementation.  I tested this out with a complex type of three levels, there is no intended logical meaning to the properties, they are simply for the purposes of example.  You could call this a spiking session, as from here on in, now I know what I am building I would take a more TDD approach.  OK, purists, why did I not do this from the start, well I didn’t, this was a brain dump and now I know what I am building I can. The console test and how I used with AutoMapper is as follows: static void Main(string[] args) { var collection = new NameValueCollection(); collection.Add("Name", "Andrew Rea"); collection.Add("Number", "1"); collection.Add("AddressLine1", "123 Street"); collection.Add("AddressNumber", "2"); collection.Add("AddressPostCodeCountry", "United Kingdom"); collection.Add("AddressPostCodeNumber", "3"); AutoMapper.Mapper.CreateMap<NameValueCollection, Person>() .ConvertUsing(x => { return(Person) RecurseType(x, typeof(Person), null); }); var person = AutoMapper.Mapper.Map<NameValueCollection, Person>(collection); Console.WriteLine(person.Name); Console.WriteLine(person.Number); Console.WriteLine(person.Address.Line1); Console.WriteLine(person.Address.Number); Console.WriteLine(person.Address.PostCode.Country); Console.WriteLine(person.Address.PostCode.Number); Console.ReadLine(); }   Notice the convention that I am using and that this method requires you do use.  Each property is prefixed with the constructed name of its parents combined.  This is the convention used by AutoMapper and it makes sense. I can also think of other uses for this including using with ASP.NET MVC ModelBinders for creating a complex type from the QueryString which is itself is a NameValueCollection. Hope this is of some help to people and I would welcome any code reviews you could give me. References: Agatha : http://code.google.com/p/agatha-rrsl/ AutoMapper : http://automapper.codeplex.com/   Cheers for now, Andrew   P.S. I will have the proposed solution for a more complete REST implementation for AGATHA very soon. 

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• Reporting Services - It's a Wrap!

  - by smisner

  If you have any experience at all with Reporting Services, you have probably developed a report using the matrix data region. It's handy when you want to generate columns dynamically based on data. If users view a matrix report online, they can scroll horizontally to view all columns and all is well. But if they want to print the report, the experience is completely different and you'll have to decide how you want to handle dynamic columns. By default, when a user prints a matrix report for which the number of columns exceeds the width of the page, Reporting Services determines how many columns can fit on the page and renders one or more separate pages for the additional columns. In this post, I'll explain two techniques for managing dynamic columns. First, I'll show how to use the RepeatRowHeaders property to make it easier to read a report when columns span multiple pages, and then I'll show you how to "wrap" columns so that you can avoid the horizontal page break. Included with this post are the sample RDLs for download. First, let's look at the default behavior of a matrix. A matrix that has too many columns for one printed page (or output to page-based renderer like PDF or Word) will be rendered such that the first page with the row group headers and the inital set of columns, as shown in Figure 1. The second page continues by rendering the next set of columns that can fit on the page, as shown in Figure 2.This pattern continues until all columns are rendered. The problem with the default behavior is that you've lost the context of employee and sales order - the row headers - on the second page. That makes it hard for users to read this report because the layout requires them to flip back and forth between the current page and the first page of the report. You can fix this behavior by finding the RepeatRowHeaders of the tablix report item and changing its value to True. The second (and subsequent pages) of the matrix now look like the image shown in Figure 3. The problem with this approach is that the number of printed pages to flip through is unpredictable when you have a large number of potential columns. What if you want to include all columns on the same page? You can take advantage of the repeating behavior of a tablix and get repeating columns by embedding one tablix inside of another. For this example, I'm using SQL Server 2008 R2 Reporting Services. You can get similar results with SQL Server 2008. (In fact, you could probably do something similar in SQL Server 2005, but I haven't tested it. The steps would be slightly different because you would be working with the old-style matrix as compared to the new-style tablix discussed in this post.) I created a dataset that queries AdventureWorksDW2008 tables: SELECT TOP (100) e.LastName + ', ' + e.FirstName AS EmployeeName, d.FullDateAlternateKey, f.SalesOrderNumber, p.EnglishProductName, sum(SalesAmount) as SalesAmount FROM FactResellerSales AS f INNER JOIN DimProduct AS p ON p.ProductKey = f.ProductKey INNER JOIN DimDate AS d ON d.DateKey = f.OrderDateKey INNER JOIN DimEmployee AS e ON e.EmployeeKey = f.EmployeeKey GROUP BY p.EnglishProductName, d.FullDateAlternateKey, e.LastName + ', ' + e.FirstName, f.SalesOrderNumber ORDER BY EmployeeName, f.SalesOrderNumber, p.EnglishProductName To start the report: Add a matrix to the report body and drag Employee Name to the row header, which also creates a group. Next drag SalesOrderNumber below Employee Name in the Row Groups panel, which creates a second group and a second column in the row header section of the matrix, as shown in Figure 4. Now for some trickiness. Add another column to the row headers. This new column will be associated with the existing EmployeeName group rather than causing BIDS to create a new group. To do this, right-click on the EmployeeName textbox in the bottom row, point to Insert Column, and then click Inside Group-Right. Then add the SalesOrderNumber field to this new column. By doing this, you're creating a report that repeats a set of columns for each EmployeeName/SalesOrderNumber combination that appears in the data. Next, modify the first row group's expression to group on both EmployeeName and SalesOrderNumber. In the Row Groups section, right-click EmployeeName, click Group Properties, click the Add button, and select [SalesOrderNumber]. Now you need to configure the columns to repeat. Rather than use the Columns group of the matrix like you might expect, you're going to use the textbox that belongs to the second group of the tablix as a location for embedding other report items. First, clear out the text that's currently in the third column - SalesOrderNumber - because it's already added as a separate textbox in this report design. Then drag and drop a matrix into that textbox, as shown in Figure 5. Again, you need to do some tricks here to get the appearance and behavior right. We don't really want repeating rows in the embedded matrix, so follow these steps: Click on the Rows label which then displays RowGroup in the Row Groups pane below the report body. Right-click on RowGroup,click Delete Group, and select the option to delete associated rows and columns. As a result, you get a modified matrix which has only a ColumnGroup in it, with a row above a double-dashed line for the column group and a row below the line for the aggregated data. Let's continue: Drag EnglishProductName to the data textbox (below the line). Add a second data row by right-clicking EnglishProductName, pointing to Insert Row, and clicking Below. Add the SalesAmount field to the new data textbox. Now eliminate the column group row without eliminating the group. To do this, right-click the row above the double-dashed line, click Delete Rows, and then select Delete Rows Only in the message box. Now you're ready for the fit and finish phase: Resize the column containing the embedded matrix so that it fits completely. Also, the final column in the matrix is for the column group. You can't delete this column, but you can make it as small as possible. Just click on the matrix to display the row and column handles, and then drag the right edge of the rightmost column to the left to make the column virtually disappear. Next, configure the groups so that the columns of the embedded matrix will wrap. In the Column Groups pane, right-click ColumnGroup1 and click on the expression button (labeled fx) to the right of Group On [EnglishProductName]. Replace the expression with the following: =RowNumber("SalesOrderNumber" ). We use SalesOrderNumber here because that is the name of the group that "contains" the embedded matrix. The next step is to configure the number of columns to display before wrapping. Click any cell in the matrix that is not inside the embedded matrix, and then double-click the second group in the Row Groups pane - SalesOrderNumber. Change the group expression to the following expression: =Ceiling(RowNumber("EmployeeName")/3) The last step is to apply formatting. In my example, I set the SalesAmount textbox's Format property to C2 and also right-aligned the text in both the EnglishProductName and the SalesAmount textboxes. And voila - Figure 6 shows a matrix report with wrapping columns. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• .NET 4.5 is an in-place replacement for .NET 4.0

  - by Rick Strahl

  With the betas for .NET 4.5 and Visual Studio 11 and Windows 8 shipping many people will be installing .NET 4.5 and hacking away on it. There are a number of great enhancements that are fairly transparent, but it's important to understand what .NET 4.5 actually is in terms of the CLR running on your machine. When .NET 4.5 is installed it effectively replaces .NET 4.0 on the machine. .NET 4.0 gets overwritten by a new version of .NET 4.5 which - according to Microsoft - is supposed to be 100% backwards compatible. While 100% backwards compatible sounds great, we all know that 100% is a hard number to hit, and even the aforementioned blog post at the Microsoft site acknowledges this. But there's so much more than backwards compatibility that makes this awkward at best and confusing at worst. What does ‘Replacement’ mean? When you install .NET 4.5 your .NET 4.0 assemblies in the \Windows\.NET Framework\V4.0.30319 are overwritten with a new set of assemblies. You end up with overwritten assemblies as well as a bunch of new ones (like the new System.Net.Http assemblies for example). The following screen shot demonstrates system.dll on my test machine (left) running .NET 4.5 on the right and my production laptop running stock .NET 4.0 (right):   Clearly they are different files with a difference in file sizes (interesting that the 4.5 version is actually smaller). That’s not all. If you actually query the runtime version when .NET 4.5 is installed with with Environment.Version you still get: 4.0.30319 If you open the properties of System.dll assembly in .NET 4.5 you'll also see: Notice that the file version is also left at 4.0.xxx. There are differences in build numbers: .NET 4.0 shows 261 and the current .NET 4.5 beta build is 17379. I suppose you can use assume a build number greater than 17000 is .NET 4.5, but that's pretty hokey to say the least. There’s no easy or obvious way to tell whether you are running on 4.0 or 4.5 – to the application they appear to be the same runtime version. And that is what Microsoft intends here. .NET 4.5 is intended as an in-place upgrade. Compile to 4.5 run on 4.0 – not quite! You can compile an application for .NET 4.5 and run it on the 4.0 runtime – that is until you hit a new feature that doesn’t exist on 4.0. At which point the app bombs at runtime. Say you write some code that is mostly .NET 4.0, but only has a few of the new features of .NET 4.5 like aync/await buried deep in the bowels of the application where it only fires occasionally. .NET will happily start your application and run everything 4.0 fine, until it hits that 4.5 code – and then crash unceremoniously at runtime. Oh joy! You can .NET 4.0 applications on .NET 4.5 of course and that should work without much fanfare. Different than .NET 3.0/3.5 Note that this in-place replacement is very different from the side by side installs of .NET 2.0 and 3.0/3.5 which all ran on the 2.0 version of the CLR. The two 3.x versions were basically library enhancements on top of the core .NET 2.0 runtime. Both versions ran under the .NET 2.0 runtime which wasn’t changed (other than for security patches and bug fixes) for the whole 3.x cycle. The 4.5 update instead completely replaces the .NET 4.0 runtime and leaves the actual version number set at v4.0.30319. When you build a new project with Visual Studio 2011, you can still target .NET 4.0 or you can target .NET 4.5. But you are in effect referencing the same set of assemblies for both regardless which version you use. What's different is the compiler used to compile and link your code so compiling with .NET 4.0 gives you just the subset of the functionality that is available in .NET 4.0, but when you use the 4.5 compiler you get the full functionality of what’s actually available in the assemblies and extra libraries. It doesn’t look like you will be able to use Visual Studio 2010 to develop .NET 4.5 applications. Good news – Bad news Microsoft is trying hard to experiment with every possible permutation of releasing new versions of the .NET framework apparently. No two updates have been the same. Clearly updating to a full new version of .NET (ie. .NET 2.0, 4.0 and at some point 5.0 runtimes) has its own set of challenges, but doing an in-place update of the runtime and then not even providing a good way to tell which version is installed is pretty whacky even by Microsoft’s standards. Especially given that .NET 4.5 includes a fairly significant update with all the aysnc functionality baked into the runtime. Most of the IO APIs have been updated to support task based async operation which significantly affects many existing APIs. To make things worse .NET 4.5 will be the initial version of .NET that ships with Windows 8 so it will be with us for a long time to come unless Microsoft finally decides to push .NET versions onto Windows machines as part of system upgrades (which currently doesn’t happen). This is the same story we had when Vista launched with .NET 3.0 which was a minor version that quickly was replaced by 3.5 which was more long lived and practical. People had enough problems dealing with the confusing versioning of the 3.x versions which ran on .NET 2.0. I can’t count the amount support calls and questions I’ve fielded because people couldn’t find a .NET 3.5 entry in the IIS version dialog. The same is likely to happen with .NET 4.5. It’s all well and good when we know that .NET 4.5 is an in-place replacement, but administrators and IT folks not intimately familiar with .NET are unlikely to understand this nuance and end up thoroughly confused which version is installed. It’s hard for me to see any upside to an in-place update and I haven’t really seen a good explanation of why this approach was decided on. Sure if the version stays the same existing assembly bindings don’t break so applications can stay running through an update. I suppose this is useful for some component vendors and strongly signed assemblies in corporate environments. But seriously, if you are going to throw .NET 4.5 into the mix, who won’t be recompiling all code and thoroughly test that code to work on .NET 4.5? A recompile requirement doesn’t seem that serious in light of a major version upgrade.  Resources http://blogs.msdn.com/b/dotnet/archive/2011/09/26/compatibility-of-net-framework-4-5.aspx http://www.devproconnections.com/article/net-framework/net-framework-45-versioning-faces-problems-141160© Rick Strahl, West Wind Technologies, 2005-2012Posted in .NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Binding collection indexes to a WPF DataGrid at runtime

  - by bearda

  After trying to develop our own control to display a table of data we stumbled on the WPF toolkit DataGrid and thought we were saved. A couple hours later I'm scratching my head trying to figure out if it can do what we really want it to do. The DataGrid seems to be based on displaying various properties of a single object, where I think I need something that can display a collection's items, I want to display a table of strings with a variable number of rows and a variable number of columns. Each row represents the state of a number of inputs at a given time. The number of samples may change, and the number of inputs may change at runtime. As a result, I can't create a custom object that represents a row with a property for each input. This makes the DataGrid binding more complicated, since I can't bind to a fixed property for each column. I thought I found a workaround for this by binding to ".[" + channelIndex + ]" but it hasn't worked out quite the way I wanted. Right now I have a collection of a collection of strings that represents the two-dimensional array of strings. I'm using ObservableCollection so string change event notifications work, but I can use any collection type needed. It looked like everything was working great until I realized that every row was showing the same line of data. Binding in C# is not my strong suit, so I'm kind of lost on what's going wrong. Is what I'm trying to do overall even possible with the WPF Toolkit DataGrid? using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; using Microsoft.Windows.Controls; using System.ComponentModel; using System.Collections; using System.Collections.ObjectModel; namespace WRE.NGDAS.UILayer { /// <summary> /// Interaction logic for DataTableControl.xaml /// </summary> public partial class DataTableControl : UserControl { #region Constants private const int lineHeight = 25; #endregion #region Type Definitions private class TableChannelInfo { internal string ChannelName = string.Empty; internal int Column = 0; public override string ToString() { return ChannelName; } } internal class NotifyString : INotifyPropertyChanged { private string text = String.Empty; public event PropertyChangedEventHandler PropertyChanged; public string Text { get { return text; } set { text = value; NotifyPropertyChanged( "Text" ); } } public NotifyString(string newText) { text = newText; } protected void NotifyPropertyChanged( string propertyChanged ) { if ( PropertyChanged != null ) { PropertyChanged(this, new PropertyChangedEventArgs(propertyChanged)); } } } #endregion #region Private Data Members string[] channels = null; int numberFixed = 0; int numberOfRows = 0; ObservableCollection<ObservableCollection<NotifyString>> tableText = null; #endregion public DataTableControl( List<string> channelNames, List<string> nameToolTips, int numberFixedColumns, int numberRows ) { InitializeComponent(); numberFixed = numberFixedColumns; numberOfRows = numberRows; tableText = new ObservableCollection<ObservableCollection<NotifyString>>(); dataGrid.ItemsSource = tableText; channels = new string[channelNames.Count]; for (int channelIndex = 0; channelIndex < channelNames.Count; channelIndex++) { channels[channelIndex] = channelNames[channelIndex]; tableText.Add(new ObservableCollection<NotifyString>()); for (int i = 0; i < numberOfRows; i++) { tableText[channelIndex].Add( new NotifyString(String.Empty) ); } Binding textBinding = new Binding( ".[" + channelIndex + "]" ); textBinding.Mode = BindingMode.OneWay; textBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged; textBinding.Source = tableText[channelIndex]; DataGridTextColumn newColumn = new DataGridTextColumn(); newColumn.Header = channelNames[channelIndex]; newColumn.DisplayIndex = channelIndex; newColumn.Binding = textBinding; if ( channelIndex < numberFixed ) { newColumn.CanUserReorder = false; } dataGrid.Columns.Add(newColumn); } //Height = lineHeight + numberOfRows * lineHeight; } internal void UpdateChannelRow( int rowNumber, List<string> channelValues, DisplayColors color ) { if ( rowNumber < numberOfRows ) { for (int column = 0; column < channelValues.Count; column++) { if ( column < channels.GetLength(0) ) { tableText[column][rowNumber].Text = channelValues[column]; } } } } } }

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• MySQL – Scalability on Amazon RDS: Scale out to multiple RDS instances

  - by Pinal Dave

  Today, I’d like to discuss getting better MySQL scalability on Amazon RDS. The question of the day: “What can you do when a MySQL database needs to scale write-intensive workloads beyond the capabilities of the largest available machine on Amazon RDS?” Let’s take a look. In a typical EC2/RDS set-up, users connect to app servers from their mobile devices and tablets, computers, browsers, etc.  Then app servers connect to an RDS instance (web/cloud services) and in some cases they might leverage some read-only replicas.   Figure 1. A typical RDS instance is a single-instance database, with read replicas.  This is not very good at handling high write-based throughput. As your application becomes more popular you can expect an increasing number of users, more transactions, and more accumulated data.  User interactions can become more challenging as the application adds more sophisticated capabilities. The result of all this positive activity: your MySQL database will inevitably begin to experience scalability pressures. What can you do? Broadly speaking, there are four options available to improve MySQL scalability on RDS. 1. Larger RDS Instances – If you’re not already using the maximum available RDS instance, you can always scale up – to larger hardware.  Bigger CPUs, more compute power, more memory et cetera. But the largest available RDS instance is still limited.  And they get expensive. “High-Memory Quadruple Extra Large DB Instance”: 68 GB of memory 26 ECUs (8 virtual cores with 3.25 ECUs each) 64-bit platform High I/O Capacity Provisioned IOPS Optimized: 1000Mbps 2. Provisioned IOPs – You can get provisioned IOPs and higher throughput on the I/O level. However, there is a hard limit with a maximum instance size and maximum number of provisioned IOPs you can buy from Amazon and you simply cannot scale beyond these hardware specifications. 3. Leverage Read Replicas – If your application permits, you can leverage read replicas to offload some reads from the master databases. But there are a limited number of replicas you can utilize and Amazon generally requires some modifications to your existing application. And read-replicas don’t help with write-intensive applications. 4. Multiple Database Instances – Amazon offers a fourth option: “You can implement partitioning,thereby spreading your data across multiple database Instances” (Link) However, Amazon does not offer any guidance or facilities to help you with this. “Multiple database instances” is not an RDS feature.  And Amazon doesn’t explain how to implement this idea. In fact, when asked, this is the response on an Amazon forum: Q: Is there any documents that describe the partition DB across multiple RDS? I need to use DB with more 1TB but exist a limitation during the create process, but I read in the any FAQ that you need to partition database, but I don’t find any documents that describe it. A: “DB partitioning/sharding is not an official feature of Amazon RDS or MySQL, but a technique to scale out database by using multiple database instances. The appropriate way to split data depends on the characteristics of the application or data set. Therefore, there is no concrete and specific guidance.” So now what? The answer is to scale out with ScaleBase. Amazon RDS with ScaleBase: What you get – MySQL Scalability! ScaleBase is specifically designed to scale out a single MySQL RDS instance into multiple MySQL instances. Critically, this is accomplished with no changes to your application code.  Your application continues to “see” one database.   ScaleBase does all the work of managing and enforcing an optimized data distribution policy to create multiple MySQL instances. With ScaleBase, data distribution, transactions, concurrency control, and two-phase commit are all 100% transparent and 100% ACID-compliant, so applications, services and tooling continue to interact with your distributed RDS as if it were a single MySQL instance. The result: now you can cost-effectively leverage multiple MySQL RDS instance to scale out write-intensive workloads to an unlimited number of users, transactions, and data. Amazon RDS with ScaleBase: What you keep – Everything! And how does this change your Amazon environment? 1. Keep your application, unchanged – There is no change your application development life-cycle at all.  You still use your existing development tools, frameworks and libraries.  Application quality assurance and testing cycles stay the same. And, critically, you stay with an ACID-compliant MySQL environment. 2. Keep your RDS value-added services – The value-added services that you rely on are all still available. Amazon will continue to handle database maintenance and updates for you. You can still leverage High Availability via Multi A-Z.  And, if it benefits youra application throughput, you can still use read replicas. 3. Keep your RDS administration – Finally the RDS monitoring and provisioning tools you rely on still work as they did before. With your one large MySQL instance, now split into multiple instances, you can actually use less expensive, smallersmaller available RDS hardware and continue to see better database performance. Conclusion Amazon RDS is a tremendous service, but it doesn’t offer solutions to scale beyond a single MySQL instance. Larger RDS instances get more expensive.  And when you max-out on the available hardware, you’re stuck.  Amazon recommends scaling out your single instance into multiple instances for transaction-intensive apps, but offers no services or guidance to help you. This is where ScaleBase comes in to save the day. It gives you a simple and effective way to create multiple MySQL RDS instances, while removing all the complexities typically caused by “DIY” sharding andwith no changes to your applications . With ScaleBase you continue to leverage the AWS/RDS ecosystem: commodity hardware and value added services like read replicas, multi A-Z, maintenance/updates and administration with monitoring tools and provisioning. SCALEBASE ON AMAZON If you’re curious to try ScaleBase on Amazon, it can be found here – Download NOW. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: MySQL, PostADay, SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• DELETE and EDIT is not working in my python program

  - by user2968025

  This is a simple python program that ADD, DELETE, EDIT and VIEW student records. The problem is, DELETE and EDIT is not working. I dont know why but when I tried removing one '?' in the DELETE dunction, I had the error that says there are only 8 columns and it needs 10. But originally, there are only 9 columns. I don't know where it got the other one to make it 10. Please help.. :( import sys import sqlite3 import tkinter import tkinter as tk from tkinter import * from tkinter.ttk import * def newRecord(): studentnum="" name="" age="" birthday="" address="" email="" course="" year="" section="" con=sqlite3.connect("Students.db") cur=con.cursor() cur.execute("CREATE TABLE IF NOT EXISTS student(studentnum TEXT, name TEXT, age TEXT, birthday TEXT, address TEXT, email TEXT, course TEXT, year TEXT, section TEXT)") def save(): studentnum=en1.get() name=en2.get() age=en3.get() birthday=en4.get() address=en5.get() email=en6.get() course=en7.get() year=en8.get() section=en9.get() student=(studentnum,name,age,birthday,address,email,course,year,section) cur.execute("INSERT INTO student(studentnum,name,age,birthday,address,email,course,year,section) VALUES(?,?,?,?,?,?,?,?,?)",student) con.commit() win=tkinter.Tk();win.title("Students") lbl=tkinter.Label(win,background="#000",foreground="#ddd",width=30,text="Add Record") lbl.pack() lbl1=tkinter.Label(win,width=30,text="Student Number : ") lbl1.pack() en1=tkinter.Entry(win,width=30) en1.pack() lbl2=tkinter.Label(win,width=30,text="Name : ") lbl2.pack() en2=tkinter.Entry(win,width=30) en2.pack() lbl3=tkinter.Label(win,width=30,text="Age : ") lbl3.pack() en3=tkinter.Entry(win,width=30) en3.pack() lbl4=tkinter.Label(win,width=30,text="Birthday : ") lbl4.pack() en4=tkinter.Entry(win,width=30) en4.pack() lbl5=tkinter.Label(win,width=30,text="Address : ") lbl5.pack() en5=tkinter.Entry(win,width=30) en5.pack() lbl6=tkinter.Label(win,width=30,text="Email : ") lbl6.pack() en6=tkinter.Entry(win,width=30) en6.pack() lbl7=tkinter.Label(win,width=30,text="Course : ") lbl7.pack() en7=tkinter.Entry(win,width=30) en7.pack() lbl8=tkinter.Label(win,width=30,text="Year : ") lbl8.pack() en8=tkinter.Entry(win,width=30) en8.pack() lbl9=tkinter.Label(win,width=30,text="Section : ") lbl9.pack() en9=tkinter.Entry(win,width=30) en9.pack() btn1=tkinter.Button(win,background="#000",foreground="#ddd",width=30,text="Save Student",command=save) btn1.pack() def editRecord(): studentnum1="" def edit(): studentnum1=en10.get() studentnum="" name="" age="" birthday="" address="" email="" course="" year="" section="" con=sqlite3.connect("Students.db") cur=con.cursor() row=cur.fetchone() cur.execute("DELETE FROM student WHERE name = '%s'" % studentnum1) con.commit() def save(): studentnum=en1.get() name=en2.get() age=en3.get() birthday=en4.get() address=en5.get() email=en6.get() course=en7.get() year=en8.get() section=en8.get() student=(studentnum,name,age,email,birthday,address,email,course,year,section) cur.execute("INSERT INTO student(studentnum,name,age,email,birthday,address,email,course,year,section) VALUES(?,?,?,?,?,?,?,?,?)",student) con.commit() win=tkinter.Tk();win.title("Students") lbl=tkinter.Label(win,background="#000",foreground="#ddd",width=30,text="Edit Reocrd :"+'\t'+studentnum1) lbl.pack() lbl1=tkinter.Label(win,width=30,text="Student Number : ") lbl1.pack() en1=tkinter.Entry(win,width=30) en1.pack() lbl2=tkinter.Label(win,width=30,text="Name : ") lbl2.pack() en2=tkinter.Entry(win,width=30) en2.pack() lbl3=tkinter.Label(win,width=30,text="Age : ") lbl3.pack() en3=tkinter.Entry(win,width=30) en3.pack() lbl4=tkinter.Label(win,width=30,text="Birthday : ") lbl4.pack() en4=tkinter.Entry(win,width=30) en4.pack() lbl5=tkinter.Label(win,width=30,text="Address : ") lbl5.pack() en5=tkinter.Entry(win,width=30) en5.pack() lbl6=tkinter.Label(win,width=30,text="Email : ") lbl6.pack() en6=tkinter.Entry(win,width=30) en6.pack() lbl7=tkinter.Label(win,width=30,text="Course : ") lbl7.pack() en7=tkinter.Entry(win,width=30) en7.pack() lbl8=tkinter.Label(win,width=30,text="Year : ") lbl8.pack() en8=tkinter.Entry(win,width=30) en8.pack() lbl9=tkinter.Label(win,width=30,text="Section : ") lbl9.pack() en9=tkinter.Entry(win,width=30) en9.pack() btn1=tkinter.Button(win,background="#000",foreground="#ddd",width=30,text="Save Record",command=save) btn1.pack() win=tkinter.Tk();win.title("Edit Student") lbl=tkinter.Label(win,background="#000",foreground="#ddd",width=30,text="Edit Record") lbl.pack() lbl10=tkinter.Label(win,width=30,text="Student Number : ") lbl10.pack() en10=tkinter.Entry(win) en10.pack() btn2=tkinter.Button(win,background="#000",foreground="#ddd",width=30,text="Edit",command=edit) btn2.pack() def deleteRecord(): studentnum1="" win=tkinter.Tk();win.title("Delete Student Record") lbl=tkinter.Label(win,background="#000",foreground="#ddd",width=30,text="Delete Record") lbl.pack() lbl10=tkinter.Label(win,text="Student Number") lbl10.pack() en10=tkinter.Entry(win) en10.pack() def delete(): studentnum1=en10.get() con=sqlite3.connect("Students.db") cur=con.cursor() row=cur.fetchone() cur.execute("DELETE FROM student WHERE name = '%s';" % studentnum1) con.commit() win=tkinter.Tk();win.title("Record Deleted") lbl=tkinter.Label(win,background="#000",foreground="#ddd",width=30,text="Record Deleted :") lbl.pack() lbl=tkinter.Label(win,width=30,text=studentnum1) lbl.pack() btn=tkinter.Button(win,background="#000",foreground="#ddd",width=30,text="Ok",command=win.destroy) btn.pack() btn2=tkinter.Button(win,background="#000",foreground="#ddd",width=30,text="Delete",command=delete) btn2.pack() def viewRecord(): con=sqlite3.connect("Students.db") cur=con.cursor() win=tkinter.Tk();win.title("View Student Record"); row=cur.fetchall() lbl1=tkinter.Label(win,background="#000",foreground="#ddd",width=300,text="\n\tStudent Number"+"\t\tName"+"\t\tAge"+"\t\tBirthday"+"\t\tAddress"+"\t\tEmail"+"\t\tCourse"+"\t\tYear"+"\t\nSection") lbl1.pack() for row in cur.execute("SELECT * FROM student"): lbl2=tkinter.Label(win,width=300,text= row[0] + '\t\t' + row[1] + '\t' + row[2] + '\t\t' + row[3] + '\t\t' + row[4] + '\t\t' + row[5] + '\t\t' + row[6] + '\t\t' + row[7] + '\t\t' + row[8] + '\n') lbl2.pack() con.close() but1=tkinter.Button(win,background="#000",foreground="#fff", width=150,text="Close",command=win.destroy) but1.pack() root=tkinter.Tk();root.title("Student Records") menubar=tkinter.Menu(root) manage=tkinter.Menu(menubar,tearoff=0) manage.add_command(label='New Record',command=newRecord) manage.add_command(label='Edit Record',command=editRecord) manage.add_command(label='Delete Record',command=deleteRecord) menubar.add_cascade(label='Manage',menu=manage) view=tkinter.Menu(menubar,tearoff=0) view.add_command(label='View Record',command=viewRecord) menubar.add_cascade(label='View',menu=view) root.config(menu=menubar) lbl=tkinter.Label(root,background="#000",foreground="#ddd",font=("Verdana",15),width=30,text="Student Records") lbl.pack() lbl1=tkinter.Label(root,text="\nSubmitted by :") lbl1.pack() lbl2=tkinter.Label(root,text="Chavez, Vissia Nicole P") lbl2.pack() lbl3=tkinter.Label(root,text="BSIT 4-4") lbl3.pack()

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• Why does Akonadi on KDE 4.6.0 refuse to start?

  - by Patches

  Akonadi refuses to start on my fresh installation of KDE 4.6.0 from the kubuntu-backports PPA on Ubuntu 10.10 Maverick Meerkat, preventing me from usking KMail. Here is the full error output: patches@pleistocene:~/.local/share$ akonadictl start Starting Akonadi Server... done. patches@pleistocene:~/.local/share$ Connecting to deprecated signal QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString) search paths: ("/home/patches/bin", "/usr/local/sbin", "/usr/local/bin", "/usr/sbin", "/usr/bin", "/sbin", "/bin", "/usr/games", "/usr/sbin", "/usr/local/sbin", "/usr/local/libexec", "/usr/libexec", "/opt/mysql/libexec", "/opt/local/lib/mysql5/bin", "/opt/mysql/sbin") Found mysql_install_db: "/usr/bin/mysql_install_db" Found mysqlcheck: "/usr/bin/mysqlcheck" Database process exited unexpectedly during initial connection! executable: "/usr/sbin/mysqld-akonadi" arguments: ("--defaults-file=/home/patches/.local/share/akonadi//mysql.conf", "--datadir=/home/patches/.local/share/akonadi/db_data/", "--socket=/home/patches/.local/share/akonadi/socket-pleistocene/mysql.socket") stdout: "" stderr: "Could not open required defaults file: /home/patches/.local/share/akonadi//mysql.conf Fatal error in defaults handling. Program aborted 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Note] Plugin 'FEDERATED' is disabled. /usr/sbin/mysqld-akonadi: Can't find file: './mysql/plugin.frm' (errno: 13) 110209 16:41:12 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 110209 16:41:12 InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means mysqld does not have the access rights to InnoDB: the directory. InnoDB: File name ./ibdata1 InnoDB: File operation call: 'create'. InnoDB: Cannot continue operation. " exit code: 1 process error: "Unknown error" "[ 0: akonadiserver(_Z11akBacktracev+0x35) [0x8086055] 1: akonadiserver() [0x8086516] 2: [0xb772e400] 3: [0xb772e416] 4: /lib/libc.so.6(gsignal+0x51) [0xb6e9f941] 5: /lib/libc.so.6(abort+0x182) [0xb6ea2e42] 6: /usr/lib/libQtCore.so.4(_Z17qt_message_output9QtMsgTypePKc+0x8c) [0xb74d62dc] 7: akonadiserver(_ZN15FileDebugStream9writeDataEPKcx+0xc4) [0x8087574] 8: /usr/lib/libQtCore.so.4(_ZN9QIODevice5writeEPKcx+0x8e) [0xb757168e] 9: /usr/lib/libQtCore.so.4(+0x103425) [0xb7581425] 10: /usr/lib/libQtCore.so.4(_ZN11QTextStreamD1Ev+0x3d) [0xb758295d] 11: akonadiserver(_ZN6QDebugD1Ev+0x43) [0x8081b73] 12: akonadiserver(_ZN13DbConfigMysql19startInternalServerEv+0x1c27) [0x810c177] 13: akonadiserver(_ZN7Akonadi13AkonadiServer20startDatabaseProcessEv+0xe3) [0x8087a23] 14: akonadiserver(_ZN7Akonadi13AkonadiServerC1EP7QObject+0xca) [0x8088b6a] 15: akonadiserver(_ZN7Akonadi13AkonadiServer8instanceEv+0x48) [0x808a1d8] 16: akonadiserver(main+0x364) [0x8080fb4] 17: /lib/libc.so.6(__libc_start_main+0xe7) [0xb6e8bce7] 18: akonadiserver() [0x8080b81] ] " ProcessControl: Application 'akonadiserver' returned with exit code 255 (Unknown error) search paths: ("/home/patches/bin", "/usr/local/sbin", "/usr/local/bin", "/usr/sbin", "/usr/bin", "/sbin", "/bin", "/usr/games", "/usr/sbin", "/usr/local/sbin", "/usr/local/libexec", "/usr/libexec", "/opt/mysql/libexec", "/opt/local/lib/mysql5/bin", "/opt/mysql/sbin") Found mysql_install_db: "/usr/bin/mysql_install_db" Found mysqlcheck: "/usr/bin/mysqlcheck" Database process exited unexpectedly during initial connection! executable: "/usr/sbin/mysqld-akonadi" arguments: ("--defaults-file=/home/patches/.local/share/akonadi//mysql.conf", "--datadir=/home/patches/.local/share/akonadi/db_data/", "--socket=/home/patches/.local/share/akonadi/socket-pleistocene/mysql.socket") stdout: "" stderr: "Could not open required defaults file: /home/patches/.local/share/akonadi//mysql.conf Fatal error in defaults handling. Program aborted 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Note] Plugin 'FEDERATED' is disabled. /usr/sbin/mysqld-akonadi: Can't find file: './mysql/plugin.frm' (errno: 13) 110209 16:41:12 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 110209 16:41:12 InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means mysqld does not have the access rights to InnoDB: the directory. InnoDB: File name ./ibdata1 InnoDB: File operation call: 'create'. InnoDB: Cannot continue operation. " exit code: 1 process error: "Unknown error" "[ 0: akonadiserver(_Z11akBacktracev+0x35) [0x8086055] 1: akonadiserver() [0x8086516] 2: [0xb77ae400] 3: [0xb77ae416] 4: /lib/libc.so.6(gsignal+0x51) [0xb6f1f941] 5: /lib/libc.so.6(abort+0x182) [0xb6f22e42] 6: /usr/lib/libQtCore.so.4(_Z17qt_message_output9QtMsgTypePKc+0x8c) [0xb75562dc] 7: akonadiserver(_ZN15FileDebugStream9writeDataEPKcx+0xc4) [0x8087574] 8: /usr/lib/libQtCore.so.4(_ZN9QIODevice5writeEPKcx+0x8e) [0xb75f168e] 9: /usr/lib/libQtCore.so.4(+0x103425) [0xb7601425] 10: /usr/lib/libQtCore.so.4(_ZN11QTextStreamD1Ev+0x3d) [0xb760295d] 11: akonadiserver(_ZN6QDebugD1Ev+0x43) [0x8081b73] 12: akonadiserver(_ZN13DbConfigMysql19startInternalServerEv+0x1c27) [0x810c177] 13: akonadiserver(_ZN7Akonadi13AkonadiServer20startDatabaseProcessEv+0xe3) [0x8087a23] 14: akonadiserver(_ZN7Akonadi13AkonadiServerC1EP7QObject+0xca) [0x8088b6a] 15: akonadiserver(_ZN7Akonadi13AkonadiServer8instanceEv+0x48) [0x808a1d8] 16: akonadiserver(main+0x364) [0x8080fb4] 17: /lib/libc.so.6(__libc_start_main+0xe7) [0xb6f0bce7] 18: akonadiserver() [0x8080b81] ] " ProcessControl: Application 'akonadiserver' returned with exit code 255 (Unknown error) search paths: ("/home/patches/bin", "/usr/local/sbin", "/usr/local/bin", "/usr/sbin", "/usr/bin", "/sbin", "/bin", "/usr/games", "/usr/sbin", "/usr/local/sbin", "/usr/local/libexec", "/usr/libexec", "/opt/mysql/libexec", "/opt/local/lib/mysql5/bin", "/opt/mysql/sbin") Found mysql_install_db: "/usr/bin/mysql_install_db" Found mysqlcheck: "/usr/bin/mysqlcheck" Database process exited unexpectedly during initial connection! executable: "/usr/sbin/mysqld-akonadi" arguments: ("--defaults-file=/home/patches/.local/share/akonadi//mysql.conf", "--datadir=/home/patches/.local/share/akonadi/db_data/", "--socket=/home/patches/.local/share/akonadi/socket-pleistocene/mysql.socket") stdout: "" stderr: "Could not open required defaults file: /home/patches/.local/share/akonadi//mysql.conf Fatal error in defaults handling. Program aborted 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Note] Plugin 'FEDERATED' is disabled. /usr/sbin/mysqld-akonadi: Can't find file: './mysql/plugin.frm' (errno: 13) 110209 16:41:12 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 110209 16:41:12 InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means mysqld does not have the access rights to InnoDB: the directory. InnoDB: File name ./ibdata1 InnoDB: File operation call: 'create'. InnoDB: Cannot continue operation. " exit code: 1 process error: "Unknown error" "[ 0: akonadiserver(_Z11akBacktracev+0x35) [0x8086055] 1: akonadiserver() [0x8086516] 2: [0xb778b400] 3: [0xb778b416] 4: /lib/libc.so.6(gsignal+0x51) [0xb6efc941] 5: /lib/libc.so.6(abort+0x182) [0xb6effe42] 6: /usr/lib/libQtCore.so.4(_Z17qt_message_output9QtMsgTypePKc+0x8c) [0xb75332dc] 7: akonadiserver(_ZN15FileDebugStream9writeDataEPKcx+0xc4) [0x8087574] 8: /usr/lib/libQtCore.so.4(_ZN9QIODevice5writeEPKcx+0x8e) [0xb75ce68e] 9: /usr/lib/libQtCore.so.4(+0x103425) [0xb75de425] 10: /usr/lib/libQtCore.so.4(_ZN11QTextStreamD1Ev+0x3d) [0xb75df95d] 11: akonadiserver(_ZN6QDebugD1Ev+0x43) [0x8081b73] 12: akonadiserver(_ZN13DbConfigMysql19startInternalServerEv+0x1c27) [0x810c177] 13: akonadiserver(_ZN7Akonadi13AkonadiServer20startDatabaseProcessEv+0xe3) [0x8087a23] 14: akonadiserver(_ZN7Akonadi13AkonadiServerC1EP7QObject+0xca) [0x8088b6a] 15: akonadiserver(_ZN7Akonadi13AkonadiServer8instanceEv+0x48) [0x808a1d8] 16: akonadiserver(main+0x364) [0x8080fb4] 17: /lib/libc.so.6(__libc_start_main+0xe7) [0xb6ee8ce7] 18: akonadiserver() [0x8080b81] ] " ProcessControl: Application 'akonadiserver' returned with exit code 255 (Unknown error) search paths: ("/home/patches/bin", "/usr/local/sbin", "/usr/local/bin", "/usr/sbin", "/usr/bin", "/sbin", "/bin", "/usr/games", "/usr/sbin", "/usr/local/sbin", "/usr/local/libexec", "/usr/libexec", "/opt/mysql/libexec", "/opt/local/lib/mysql5/bin", "/opt/mysql/sbin") Found mysql_install_db: "/usr/bin/mysql_install_db" Found mysqlcheck: "/usr/bin/mysqlcheck" Database process exited unexpectedly during initial connection! executable: "/usr/sbin/mysqld-akonadi" arguments: ("--defaults-file=/home/patches/.local/share/akonadi//mysql.conf", "--datadir=/home/patches/.local/share/akonadi/db_data/", "--socket=/home/patches/.local/share/akonadi/socket-pleistocene/mysql.socket") stdout: "" stderr: "Could not open required defaults file: /home/patches/.local/share/akonadi//mysql.conf Fatal error in defaults handling. Program aborted 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Warning] Can't create test file /home/patches/.local/share/akonadi/db_data/pleistocene.lower-test 110209 16:41:12 [Note] Plugin 'FEDERATED' is disabled. /usr/sbin/mysqld-akonadi: Can't find file: './mysql/plugin.frm' (errno: 13) 110209 16:41:12 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 110209 16:41:12 InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means mysqld does not have the access rights to InnoDB: the directory. InnoDB: File name ./ibdata1 InnoDB: File operation call: 'create'. InnoDB: Cannot continue operation. " exit code: 1 process error: "Unknown error" "[ 0: akonadiserver(_Z11akBacktracev+0x35) [0x8086055] 1: akonadiserver() [0x8086516] 2: [0xb784e400] 3: [0xb784e416] 4: /lib/libc.so.6(gsignal+0x51) [0xb6fbf941] 5: /lib/libc.so.6(abort+0x182) [0xb6fc2e42] 6: /usr/lib/libQtCore.so.4(_Z17qt_message_output9QtMsgTypePKc+0x8c) [0xb75f62dc] 7: akonadiserver(_ZN15FileDebugStream9writeDataEPKcx+0xc4) [0x8087574] 8: /usr/lib/libQtCore.so.4(_ZN9QIODevice5writeEPKcx+0x8e) [0xb769168e] 9: /usr/lib/libQtCore.so.4(+0x103425) [0xb76a1425] 10: /usr/lib/libQtCore.so.4(_ZN11QTextStreamD1Ev+0x3d) [0xb76a295d] 11: akonadiserver(_ZN6QDebugD1Ev+0x43) [0x8081b73] 12: akonadiserver(_ZN13DbConfigMysql19startInternalServerEv+0x1c27) [0x810c177] 13: akonadiserver(_ZN7Akonadi13AkonadiServer20startDatabaseProcessEv+0xe3) [0x8087a23] 14: akonadiserver(_ZN7Akonadi13AkonadiServerC1EP7QObject+0xca) [0x8088b6a] 15: akonadiserver(_ZN7Akonadi13AkonadiServer8instanceEv+0x48) [0x808a1d8] 16: akonadiserver(main+0x364) [0x8080fb4] 17: /lib/libc.so.6(__libc_start_main+0xe7) [0xb6fabce7] 18: akonadiserver() [0x8080b81] ] " ProcessControl: Application 'akonadiserver' returned with exit code 255 (Unknown error) "akonadiserver" crashed too often and will not be restarted! I tried moving the ~/.local/share/akonadi folder and running it fresh, and I also tried starting Akonadi from a brand new user, all to no avail. Requested by @djeikyb: patches@pleistocene:~$ ls -ld ~/.local drwxrwx--- 3 patches patches 4096 2011-02-07 03:15 /home/patches/.local patches@pleistocene:~$ mysql_upgrade Looking for 'mysql' as: mysql Looking for 'mysqlcheck' as: mysqlcheck Running 'mysqlcheck' with connection arguments: '--port=3306' '--socket=/var/run/mysqld/mysqld.sock' mysqlcheck: Got error: 2002: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) when trying to connect FATAL ERROR: Upgrade failed patches@pleistocene:~$ mysql_upgrade -S ~/.local/share/akonadi/socket-pleistocene/ Looking for 'mysql' as: mysql Looking for 'mysqlcheck' as: mysqlcheck Running 'mysqlcheck' with connection arguments: '--port=3306' '--socket=/var/run/mysqld/mysqld.sock' '--socket=/home/patches/.local/share/akonadi/socket-pleistocene/' mysqlcheck: Got error: 2002: Can't connect to local MySQL server through socket '/home/patches/.local/share/akonadi/socket-pleistocene/' (111) when trying to connect FATAL ERROR: Upgrade failed

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• C - array count, strtok, etc

  - by Pedro

  Hi... i have a little problem on my code... HI open a txt that have this: LEI;7671;Maria Albertina da silva;[email protected]; 9;8;12;9;12;11;6;15;7;11; LTCGM;6567;Artur Pereira Ribeiro;[email protected]; 6;13;14;12;11;16;14; LEI;7701;Ana Maria Carvalho;[email protected]; 8;13;11;7;14;12;11;16;14; LEI, LTCGM are the college; 7671, 6567, 7701 is student number; Maria, Artur e Ana are the students name; [email protected], ...@gmail are emails from students; the first number of every line is the total of classes that students have; after that is students school notes; example: College: LEI Number: 7671 Name: Maria Albertina da Silva email: [email protected] total of classes: 9 Classe Notes: 8 12 9 12 11 6 15 7 11. My code: typedef struct aluno{ char sigla[5];//college char numero[80];//number char nome[80];//student name char email[20];//email int total_notas;// total of classes char tot_not[40]; // total classes char notas[20];// classe notes int nota; //class notes char situacao[80]; //situation (aproved or disaproved) }ALUNO; void ordena(ALUNO*alunos, int tam)//bubble sort { int i=0; int j=0; char temp[100]; for( i=0;i<tam;i++) for(j=0;j<tam-1;j++) if(strcmp( alunos[i].sigla[j], alunos[i].sigla[j+1])>0){ strcpy(temp, alunos[i].sigla[j]); strcpy(alunos[i].sigla[j],alunos[i].sigla[j+1]); strcpy(alunos[i].sigla[j+1], temp); } } void xml(ALUNO*alunos, int tam){ FILE *fp; char linha[60];//line int soma, max, min, count;//biggest note and lowest note and students per course count float media; //media of notes fp=fopen("example.txt","r"); if(fp==NULL){ exit(1); } else{ while(!(feof(fp))){ soma=0; media=0; max=0; min=0; count=0; fgets(linha,60,fp); if(linha[0]=='L'){ if(ap_dados=strtok(linha,";")){ strcpy(alunos[i].sigla,ap_dados);//copy to struct // i need to call bubble sort here, but i don't know how printf("College: %s\n",alunos[i].sigla); if(ap_dados=strtok(NULL,";")){ strcpy(alunos[i].numero,ap_dados);//copy to struct printf("number: %s\n",alunos[i].numero); if(ap_dados=strtok(NULL,";")){ strcpy(alunos[i].nome, ap_dados);//copy to struct printf("name: %s\n",alunos[i].nome); if(ap_dados=strtok(NULL,";")){ strcpy(alunos[i].email, ap_dados);//copy to struct printf("email: %s\n",alunos[i].email); } } } }i++; } if(isdigit(linha[0])){ if(info_notas=strtok(linha,";")){ strcpy(alunos[i].tot_not,info_notas); alunos[i].total_notas=atoi(alunos[i].tot_not);//total classes for(z=0;z<=alunos[i].total_notas;z++){ if(info_notas=strtok(NULL,";")){ strcpy(alunos[i].notas,info_notas); alunos[i].nota=atoi(alunos[i].notas); // student class notes } soma=soma + alunos[i].nota; media=soma/alunos[i].total_notas;//doesn't work if(alunos[i].nota>max){ max=alunos[i].nota;;//doesn't work } else{ if(min<alunos[i].nota){ min=alunos[i].nota;;//doesn't work } } //now i need to count the numbers of students in the same college, but doesn't work /*If(strcmp(alunos[i].sigla, alunos[i+1].sigla)=0){ count ++; printf("%d\n", count); here for LEI should appear 2 students and for LTCGM appear 1, don't work }*/ //Now i need to see if student is aproved or disaproved // Student is disaproved if he gets 3 notes under 10, how can i do that? } printf("media %d\n",media); //media printf("Nota maxima %d\n",max);// biggest note printf("Nota minima %d\n",min); //lowest note }i++; } } } fclose(fp); } int main(int argc, char *argv[]){ ALUNO alunos; FILE *fp; int tam; fp=fopen(nomeFicheiro,"r"); alunos = (ALUNO*) calloc (tam, sizeof(ALUNO)); xml(alunos,nomeFicheiro, tam); system("PAUSE"); return 0; }

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• At most how many customized P3 attributes could be added into Agile?

  - by Jie Chen

  I have one customer/Oracle Partner Consultant asking me such question: how many customized attributes can be allowed to add to Agile's subclass Page Three? I never did research against this because Agile User Guide never says this and theoretically Agile supports unlimited amount of customized attributes, unless the browser itself cannot handle them in allocated memory. However my customers says when to add almost 1000 attributes, the browser (Web Client) will not show any Page Three attributes, including all the out-of-box attributes. Let's see why. Analysis It is horrible to add 1000 attributes manually. Let's do it by a batch SQL like below to add them to Item's subclass Page Three tab. Do not execute below SQL because it will not take effect due to your different node id. CREATE OR REPLACE PROCEDURE createP3Text(v_name IN VARCHAR2) IS v_nid NUMBER; v_pid NUMBER; BEGIN select SEQNODETABLE.nextval into v_nid from dual; Insert Into nodeTable ( id,parentID,description,objType,inherit,helpID,version,name ) values ( v_nid,2473003, v_name ,1,0,0,0, v_name); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,1,0,1,925, null); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,0,0,0,0,1,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,0,0,0,0,2,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,2,2,0,1,3,'50'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,1,0,1,5, null); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,2,0,1,6,'50'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,2,0,0,7,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,1,8,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,1,9,'1'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,2,1,0,1,10,v_name); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,0,0,0,0,11,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,11743,1,14,'2'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,1,0,1,30, null); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,2,1,0,1,38, null); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,451,0,59,'1'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,451,0,60,'1'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,724,0,61, null); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,2,1,0,0,232,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,451,0,233,'1'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,12239,1,415,'13307'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,2,1,0,0,605,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,1,610,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,1,4,1,451,0,716,'1'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,1,795,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,2000008821,1,864,'2'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,1,923,'0'); Insert Into propertyTable ( ID,parentID,readOnly,attType,dataType,selection,visible,propertyID,value ) values ( SEQPROPERTYTABLE.nextval,v_nid,0,4,1,451,0,719,'0'); Insert Into tableInfo ( tabID,tableID,classID,att,ordering ) values ( 2473005,1501,2473002,v_nid,9999); commit; END createP3Text; / BEGIN FOR i in 1..1000 LOOP createP3Text('MyText' || i); END LOOP; END; / DROP PROCEDURE createP3Text; COMMIT; Now restart Agile Server and check the Server's log, we noticed below: ***** Node Created : 85625 ***** Property Created : 184579 +++++++++++++++++++++++++++++++++++++ + Agile PLM Server Starting Up... + +++++++++++++++++++++++++++++++++++++ However the previously log before batch SQL is ***** Node Created : 84625 ***** Property Created : 157579 +++++++++++++++++++++++++++++++++++++ + Agile PLM Server Starting Up... + +++++++++++++++++++++++++++++++++++++ Obviously we successfully imported 1000 (85625-84625) attributes. Now go to JavaClient and confirm if we have them or not. Theoretically we are able to open such item object and see all these 1000 attributes and their values, but we get below error. We have no error tips in server log. But never mind we have the Java Console for JavaClient. If to open the same item in JavaClient we get a clear error and detailed trace in Java Console. ORA-01795: maximum number of expressions in a list is 1000 java.sql.SQLException: ORA-01795: maximum number of expressions in a list is 1000 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:125) ... ... at weblogic.jdbc.wrapper.PreparedStatement.executeQuery(PreparedStatement.java:128) at com.agile.pc.cmserver.base.AgileFlexUtil.setFlexValuesForOneRowTable(AgileFlexUtil.java:1104) at com.agile.pc.cmserver.base.BaseFlexTableDAO.loadExtraFlexAttValues(BaseFlexTableDAO.java:111) at com.agile.pc.cmserver.base.BasePageThreeDAO.loadTable(BasePageThreeDAO.java:108) If you are interested in the background of the problem, you may de-compile the class com.agile.pc.cmserver.base.AgileFlexUtil.setFlexValuesForOneRowTable and find the root cause that Agile happens to hit Oracle Database's limitation that more than 1000 values in the "IN" clause. Check here http://ora-01795.ora-code.com If you need Oracle Agile's final solution, please contact Oracle Agile Support. Performance Below two screenshot are jvm heap usage from before-SQL and after-SQL. We can see there is no big memory gap between two cases. So definitely there is no performance impact to Agile Application Server unless you have more than 1000 attributes for EACH of your dozens of  subclasses. And for client, 1000 attributes should not impact the browser's performance because in HTML we only use dt and dd for each attribute's pair: label and value. It is quite lightweight.

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• Anatomy of a .NET Assembly - PE Headers

  - by Simon Cooper

  Today, I'll be starting a look at what exactly is inside a .NET assembly - how the metadata and IL is stored, how Windows knows how to load it, and what all those bytes are actually doing. First of all, we need to understand the PE file format. PE files .NET assemblies are built on top of the PE (Portable Executable) file format that is used for all Windows executables and dlls, which itself is built on top of the MSDOS executable file format. The reason for this is that when .NET 1 was released, it wasn't a built-in part of the operating system like it is nowadays. Prior to Windows XP, .NET executables had to load like any other executable, had to execute native code to start the CLR to read & execute the rest of the file. However, starting with Windows XP, the operating system loader knows natively how to deal with .NET assemblies, rendering most of this legacy code & structure unnecessary. It still is part of the spec, and so is part of every .NET assembly. The result of this is that there are a lot of structure values in the assembly that simply aren't meaningful in a .NET assembly, as they refer to features that aren't needed. These are either set to zero or to certain pre-defined values, specified in the CLR spec. There are also several fields that specify the size of other datastructures in the file, which I will generally be glossing over in this initial post. Structure of a PE file Most of a PE file is split up into separate sections; each section stores different types of data. For instance, the .text section stores all the executable code; .rsrc stores unmanaged resources, .debug contains debugging information, and so on. Each section has a section header associated with it; this specifies whether the section is executable, read-only or read/write, whether it can be cached... When an exe or dll is loaded, each section can be mapped into a different location in memory as the OS loader sees fit. In order to reliably address a particular location within a file, most file offsets are specified using a Relative Virtual Address (RVA). This specifies the offset from the start of each section, rather than the offset within the executable file on disk, so the various sections can be moved around in memory without breaking anything. The mapping from RVA to file offset is done using the section headers, which specify the range of RVAs which are valid within that section. For example, if the .rsrc section header specifies that the base RVA is 0x4000, and the section starts at file offset 0xa00, then an RVA of 0x401d (offset 0x1d within the .rsrc section) corresponds to a file offset of 0xa1d. Because each section has its own base RVA, each valid RVA has a one-to-one mapping with a particular file offset. PE headers As I said above, most of the header information isn't relevant to .NET assemblies. To help show what's going on, I've created a diagram identifying all the various parts of the first 512 bytes of a .NET executable assembly. I've highlighted the relevant bytes that I will refer to in this post: Bear in mind that all numbers are stored in the assembly in little-endian format; the hex number 0x0123 will appear as 23 01 in the diagram. The first 64 bytes of every file is the DOS header. This starts with the magic number 'MZ' (0x4D, 0x5A in hex), identifying this file as an executable file of some sort (an .exe or .dll). Most of the rest of this header is zeroed out. The important part of this header is at offset 0x3C - this contains the file offset of the PE signature (0x80). Between the DOS header & PE signature is the DOS stub - this is a stub program that simply prints out 'This program cannot be run in DOS mode.\r\n' to the console. I will be having a closer look at this stub later on. The PE signature starts at offset 0x80, with the magic number 'PE\0\0' (0x50, 0x45, 0x00, 0x00), identifying this file as a PE executable, followed by the PE file header (also known as the COFF header). The relevant field in this header is in the last two bytes, and it specifies whether the file is an executable or a dll; bit 0x2000 is set for a dll. Next up is the PE standard fields, which start with a magic number of 0x010b for x86 and AnyCPU assemblies, and 0x20b for x64 assemblies. Most of the rest of the fields are to do with the CLR loader stub, which I will be covering in a later post. After the PE standard fields comes the NT-specific fields; again, most of these are not relevant for .NET assemblies. The one that is is the highlighted Subsystem field, and specifies if this is a GUI or console app - 0x20 for a GUI app, 0x30 for a console app. Data directories & section headers After the PE and COFF headers come the data directories; each directory specifies the RVA (first 4 bytes) and size (next 4 bytes) of various important parts of the executable. The only relevant ones are the 2nd (Import table), 13th (Import Address table), and 15th (CLI header). The Import and Import Address table are only used by the startup stub, so we will look at those later on. The 15th points to the CLI header, where the CLR-specific metadata begins. After the data directories comes the section headers; one for each section in the file. Each header starts with the section's ASCII name, null-padded to 8 bytes. Again, most of each header is irrelevant, but I've highlighted the base RVA and file offset in each header. In the diagram, you can see the following sections: .text: base RVA 0x2000, file offset 0x200 .rsrc: base RVA 0x4000, file offset 0xa00 .reloc: base RVA 0x6000, file offset 0x1000 The .text section contains all the CLR metadata and code, and so is by far the largest in .NET assemblies. The .rsrc section contains the data you see in the Details page in the right-click file properties page, but is otherwise unused. The .reloc section contains address relocations, which we will look at when we study the CLR startup stub. What about the CLR? As you can see, most of the first 512 bytes of an assembly are largely irrelevant to the CLR, and only a few bytes specify needed things like the bitness (AnyCPU/x86 or x64), whether this is an exe or dll, and the type of app this is. There are some bytes that I haven't covered that affect the layout of the file (eg. the file alignment, which determines where in a file each section can start). These values are pretty much constant in most .NET assemblies, and don't affect the CLR data directly. Conclusion To summarize, the important data in the first 512 bytes of a file is: DOS header. This contains a pointer to the PE signature. DOS stub, which we'll be looking at in a later post. PE signature PE file header (aka COFF header). This specifies whether the file is an exe or a dll. PE standard fields. This specifies whether the file is AnyCPU/32bit or 64bit. PE NT-specific fields. This specifies what type of app this is, if it is an app. Data directories. The 15th entry (at offset 0x168) contains the RVA and size of the CLI header inside the .text section. Section headers. These are used to map between RVA and file offset. The important one is .text, which is where all the CLR data is stored. In my next post, we'll start looking at the metadata used by the CLR directly, which is all inside the .text section.

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• More Fun With Math

  - by PointsToShare

  More Fun with Math   The runaway student – three different ways of solving one problem Here is a problem I read in a Russian site: A student is running away. He is moving at 1 mph. Pursuing him are a lion, a tiger and his math teacher. The lion is 40 miles behind and moving at 6 mph. The tiger is 28 miles behind and moving at 4 mph. His math teacher is 30 miles behind and moving at 5 mph. Who will catch him first? Analysis Obviously we have a set of three problems. They are all basically the same, but the details are different. The problems are of the same class. Here is a little excursion into computer science. One of the things we strive to do is to create solutions for classes of problems rather than individual problems. In your daily routine, you call it re-usability. Not all classes of problems have such solutions. If a class has a general (re-usable) solution, it is called computable. Otherwise it is unsolvable. Within unsolvable classes, we may still solve individual (some but not all) problems, albeit with different approaches to each. Luckily the vast majority of our daily problems are computable, and the 3 problems of our runaway student belong to a computable class. So, let’s solve for the catch-up time by the math teacher, after all she is the most frightening. She might even make the poor runaway solve this very problem – perish the thought! Method 1 – numerical analysis. At 30 miles and 5 mph, it’ll take her 6 hours to come to where the student was to begin with. But by then the student has advanced by 6 miles. 6 miles require 6/5 hours, but by then the student advanced by another 6/5 of a mile as well. And so on and so forth. So what are we to do? One way is to write code and iterate it until we have solved it. But this is an infinite process so we’ll end up with an infinite loop. So what to do? We’ll use the principles of numerical analysis. Any calculator – your computer included – has a limited number of digits. A double floating point number is good for about 14 digits. Nothing can be computed at a greater accuracy than that. This means that we will not iterate ad infinidum, but rather to the point where 2 consecutive iterations yield the same result. When we do financial computations, we don’t even have to go that far. We stop at the 10th of a penny.  It behooves us here to stop at a 10th of a second (100 milliseconds) and this will how we will avoid an infinite loop. Interestingly this alludes to the Zeno paradoxes of motion – in particular “Achilles and the Tortoise”. Zeno says exactly the same. To catch the tortoise, Achilles must always first come to where the tortoise was, but the tortoise keeps moving – hence Achilles will never catch the tortoise and our math teacher (or lion, or tiger) will never catch the student, or the policeman the thief. Here is my resolution to the paradox. The distance and time in each step are smaller and smaller, so the student will be caught. The only thing that is infinite is the iterative solution. The race is a convergent geometric process so the steps are diminishing, but each step in the solution takes the same amount of effort and time so with an infinite number of steps, we’ll spend an eternity solving it.  This BTW is an original thought that I have never seen before. But I digress. Let’s simply write the code to solve the problem. To make sure that it runs everywhere, I’ll do it in JavaScript. function LongCatchUpTime(D, PV, FV) // D is Distance; PV is Pursuers Velocity; FV is Fugitive’ Velocity {     var t = 0;     var T = 0;     var d = parseFloat(D);     var pv = parseFloat (PV);     var fv = parseFloat (FV);     t = d / pv;     while (t > 0.000001) //a 10th of a second is 1/36,000 of an hour, I used 1/100,000     {         T = T + t;         d = t * fv;         t = d / pv;     }     return T;     } By and large, the higher the Pursuer’s velocity relative to the fugitive, the faster the calculation. Solving this with the 10th of a second limit yields: 7.499999232000001 Method 2 – Geometric Series. Each step in the iteration above is smaller than the next. As you saw, we stopped iterating when the last step was small enough, small enough not to really matter.  When we have a sequence of numbers in which the ratio of each number to its predecessor is fixed we call the sequence geometric. When we are looking at the sum of sequence, we call the sequence of sums series.  Now let’s look at our student and teacher. The teacher runs 5 times faster than the student, so with each iteration the distance between them shrinks to a fifth of what it was before. This is a fixed ratio so we deal with a geometric series.  We normally designate this ratio as q and when q is less than 1 (0 < q < 1) the sum of  + … +  is  – 1) / (q – 1). When q is less than 1, it is easier to use ) / (1 - q). Now, the steps are 6 hours then 6/5 hours then 6/5*5 and so on, so q = 1/5. And the whole series is multiplied by 6. Also because q is less than 1 , 1/  diminishes to 0. So the sum is just  / (1 - q). or 1/ (1 – 1/5) = 1 / (4/5) = 5/4. This times 6 yields 7.5 hours. We can now continue with some algebra and take it back to a simpler formula. This is arduous and I am not going to do it here. Instead let’s do some simpler algebra. Method 3 – Simple Algebra. If the time to capture the fugitive is T and the fugitive travels at 1 mph, then by the time the pursuer catches him he travelled additional T miles. Time is distance divided by speed, so…. (D + T)/V = T  thus D + T = VT  and D = VT – T = (V – 1)T  and T = D/(V – 1) This “strangely” coincides with the solution we just got from the geometric sequence. This is simpler ad faster. Here is the corresponding code. function ShortCatchUpTime(D, PV, FV) {     var d = parseFloat(D);     var pv = parseFloat (PV);     var fv = parseFloat (FV);     return d / (pv - fv); } The code above, for both the iterative solution and the algebraic solution are actually for a larger class of problems.  In our original problem the student’s velocity (speed) is 1 mph. In the code it may be anything as long as it is less than the pursuer’s velocity. As long as PV > FV, the pursuer will catch up. Here is the really general formula: T = D / (PV – FV) Finally, let’s run the program for each of the pursuers.  It could not be worse. I know he’d rather be eaten alive than suffering through yet another math lesson. See the code run? Select  “Catch Up Time” in www.mgsltns.com/games.htm The host is running on Unix, so the link is case sensitive. That’s All Folks

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• Thoughts on the Nomination Committee Campaign 2014

  - by Testas

  Congratulations to Erin, Andy and Allen on making the Nomination Committee for 2014. As Mark Broadbent (@retracement) stated in his tweet, there’s a great set of individuals for the Nom Com, and I could not agree more. I know Erin and Allen, and I know how much value they will bring to the process. I don’t know Andy as well, but I am sure he will do a great job and I hope I can meet him at PASS soon. The final candidate appointed by the PASS board is Rick Bolesta, who brings a wealth of experience to the process. I also want to take the opportunity to thank all who have voted. Not just for me, but for all the candidates during the election. Your contribution is greatly appreciated. Would I apply for the Nom Com again?  Yes I would. My first election experience has been a learning experience in itself. So I accept the result and look forward to applying next year. Moving on from this, I do want to express my opinion about the lack of international representation in the election process. One of the tweets that I saw after the result was from Adam Machanic (@AdamMachanic) who commented on the lack of international members on the Nom Com. If truth be told, I was disappointed – when the candidate list was released -- that for the second time in recent elections there was a lack of international candidates on the candidate list. It feels that only Brits and Americans partake in such elections. This is a real shame, and I can’t help thinking why this is the case. Hugo Kornelis (@Hugo_Kornelis) wrote a blog here to express his thoughts. He did raise some valid points. I don’t know why there is an absence of international candidates. I know that the team at PASS are looking to improve the situation, so I do not want to give the impression that PASS are doing nothing. For reference please see Bill Graziano’ s article here to see how PASS are addressing the situation. There is a clear direction to change the rules within PASS to give greater inclusion of international members. In addition to this, I wanted to explore a couple of potential approaches to address the situation. I am not saying that they are the right answer, but when I see challenges, I like to bring potential solutions to the table. 1.       Use the PASS mission statement to define a tactical objective that engages community leaders into the election process. If you are not familiar with the PASS mission statement, let me provide it here as laid out on the PASS website. “Empower data professionals who leverage Microsoft technologies to connect, share, and learn through networking, knowledge sharing, and peer-based learning” PASS fulfil this mission statement regularly. Whether you attend SQL Saturday, SQLRally, SQLPASS and BA conference itself. The biggest value of PASS is the ability to bring our profession together. And the 24 hour hop allows you to learn from the comfort of your own office/home. This mission should be extended to define a tactical objectives that bring greater networking and knowledge sharing between PASS Chapter leaders/Regional Mentors and PASS HQ. It should help educate the leaders about the opportunities of elections and how leaders can become involved. I know PASS engage with Chapter leaders on a regular basis to discuss community matters for the benefit of PASS members. How could this be achieved? Perhaps PASS could perform a quarterly virtual meeting that specifically looks at helping leaders become more involved with the election process 2.       Evolve the Global Growth Strategy into a Global Engagement Strategy. One of the remits of the PASS board over the last couple of years is the Global Growth strategy. This has been very successful as we have seen the massive growth of events across the world. For that, I congratulate the board for this success. Perhaps the time is now right to look at solidifying this success, through a Global Engagement Strategy that starts with the collaboration of Chapter Leaders, Regional Mentors and Evangelists in their respective Countries or Regions. The engagement strategy should look at increasing collaboration between community leaders for the benefit of their respective communities. It should also provide a channel for encouraging leaders to put themselves forward for the elections. How could this be achieved? In the UK, there has been a big growth in PASS Chapters and SQL Server Events that was approaching saturation point. The introduction of the Community Engagement Day -- channelled through the SQLBits conference -- has enabled Chapter Leaders to collaborate, connect and share with PASS, Sponsors and Microsoft. It also provides the ability for Chapter Leaders to speak directly to the PASS representatives from PASSHQ. This brings with it the ability for PASS community evangelists to communicate PASS objectives. It has also been the event where we have found out; and/or encouraged, Chapter Leaders to put themselves forward for elections. People like encouragement and validation when going for something like an election, and being able to discuss this with peers at a dedicated event provides a useful platform. PASS has the people in place already to facilitate such an event. Regional Mentors could potentially help organise such events on an annual basis, with PASSHQ providing support in providing a room/Lync access for the event to take place. It would be really good if a PASSHQ representative could attend in person as well.   3.       Restrict candidates to serve only a limited number of terms. A frequent comment I saw on social networking was that the elections can be seen by some as a popularity conference. Perhaps by limiting the number of terms that an individual can serve on either the Nom Com or the BOD, other candidates may be encouraged to be more actively involved within the PASS election process. I don’t think that the current byelaws deal with this particular suggestion. I also saw a couple of tweets that stated that more active community members did not apply for the Nom Com. I struggled to understand how the individuals of the tweets measured “more active”. It just also further solidified the subjective nature of elections. In the absence of how candidates are put forward for the elections. Then a restriction of terms enables the opportunity to be extended to others. How could this be achieved? Set a resolution that is put to a community vote as to the viability of such a solution. For example, the questions for the vote could be: Should individuals in the Nom Com and BoD be limited to a certain number of terms?  Yes/No. What is the maximum number of terms a candidate could serve?   It would be simple to execute such a vote, and the community will have an opportunity to have a say in an important aspect of the PASS organisation. And is the change is successful, then add it as a byelaw.   So there are some of my thoughts. I am not saying they are right or wrong. But I do hope that there is a concerted effort to encourage more candidates from other reaches of the Globe to become involved with future elections.   It would be good to hear your thoughts   Thanks   Chris

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• WhatsApp &amp; Tasker for Android &ndash; Read &amp; Write messages

  - by Shaurya Anand

  So, I finally gave up on all my previous the Microsoft Mobile/Phone OS devices and made my switch to Android this year. I am using my Samsung Galaxy Note GT-N7000 with CyanogenMod 9.1.0 (http://get.cm/get/jenkins/7086/cm-9.1.0-n7000.zip) and ClockworkMod 6.0.1.2 (http://download2.clockworkmod.com/recoveries/recovery-clockwork-6.0.1.2-n7000.zip) since August this year and I am so happy with the performance and the flexibility it offers me. As a software developer by profession, I would expect most of my gadget to be highly customizable and programmable (one time or at intervals) to suit my needs as close as it can. I was introduced to Automation for Android – Tasker (https://play.google.com/store/apps/details?id=net.dinglisch.android.taskerm&hl=en) via reddit (http://www.reddit.com/r/tasker) and the word ‘automation’ was enough for me to dive right into this app. Only automation that I did earlier was switching profiles depending on location on there phones. And now, just imagine a complete set of possibilities that can be automate on the phone or via the phone. I did my research and found a couple of other tools that do the same/as close as what Tasker can do and few of them are even free. There’s one even by Microsoft called on{X} (https://play.google.com/store/apps/details?id=com.microsoft.onx.app&hl=en). Microsoft’s on{X} really caught my eye. You can write code for your phone on the web application by them, deploy it on your phone and even trace the flow all using your PC. Really brilliant, I love the fact that it’s all JavaScript. Here comes the but, it is still very very young and it’s policy of accessing my News Feed on Facebook is not something that I can not digest. On{X} is good, but as I said earlier, the API is not very mature and hence, I gave up on it. I bought Tasker, the best 5,00 € I spent in ages and I want to talk about it in this post. I am still a “noob” while operating this tool, but I tried my shot at automating WhatsApp (https://play.google.com/store/apps/details?id=com.whatsapp&hl=en), a popular messenger for various platform. The requirement for the automation is that, if I send a WhatsApp ‘wru’ message to the phone, it should respond back giving the location and battery level of my phone. It could be useful, if you like to locate your misplaced phone or automatically reply to your partner/friend, honestly, I don’t know what you will use it - through this post, I am just introducing automating WhatsApp using Tasker. Before we begin, the following script only works when your phone is rooted as we will be accessing the WhatsApp database and type some special characters like ‘:’. Let’s follow the code line by line: Profile:         Location request from XYZ. (12) // Name of your profile. Event:         Notification [ Owner Application:WhatsApp Title:* ] // When a new notification comes from WhatsApp, this event is fired. Read the end note, if you face problems with Chrome app after enabling Tasker accessibility. Enter:         A1: Run Shell [ Command:sqlite3 // We will access the WhatsApp database and check if the message comes from designated phone number or not. We mustn’t reply to every message.                 /data/data/com.whatsapp/databases/msgstore.db "SELECT _id, data FROM                  messages WHERE key_from_me='0' AND key_remote_jid LIKE '%XXXXXXXXXXX%' // Replace XXXXXXXXXXX with the phone number of your message sender.                 ORDER BY _id DESC LIMIT 1;" Timeout (Seconds):10 Use Root:On Store // I made a timeout for 10 seconds, if in case WhatsApp is busy accessing the database.                 Result In:%WHATSAPP_CURRREQ ] // Store the read Id and the last message on to the variable %WHATSAPP_CURRREQ         A2: If [ %WHATSAPP_CURRREQ ~R .*[wW][rR][uU].* ] // Check if the pattern of the message is correct and we are all set to send the location.                 A3: If [ %WHATSAPP_CURRREQ !~ %WHATSAPP_LASTREQ ] // Verify that the message is different from the last request. Remember every message has a unique Id.                         A4: Notify [ Title:WhatsApp location request... Text:Sending location // Just a notification that the location message is being prepared.                                 to Krati Gupta... Icon:<icon> Number:0 Permanent:On Priority:3 ] // Make a note it is a permanent notification, we will clear it later.                         A5: Secure Settings [ Configuration:Pattern Lock Disabled // I am disabling the pattern lock, that I use using the plugin Secure Settings.                                 Package:com.intangibleobject.securesettings.plugin Name:Secure // You can download the plugin from here: https://play.google.com/store/apps/details?id=com.intangibleobject.securesettings.plugin&hl=en                                 Settings ]                         A6: Secure Settings [ Configuration:Keyguard Disabled // Disable the keygaurd, it is useful, when your phone is on lock and you want to automate everything, even the typing.                                 Package:com.intangibleobject.securesettings.plugin Name:Secure                                 Settings ]                         A7: Secure Settings [ Configuration:GPS Enabled // Pretty clear, turn on the GPS and get location at A8                                 Package:com.intangibleobject.securesettings.plugin Name:Secure                                 Settings ]                         A8: AutoShortcut [ Configuration:WhatsApp: Some One // I am using AutoShortcut plugin (https://play.google.com/store/apps/details?id=com.joaomgcd.autoshortcut) to start WhatsApp with the indented recipient.                                 Package:com.joaomgcd.autoshortcut Name:AutoShortcut ] // Replace Some One, actually choose it from the plugin, the right recipient.                         A9: Get Location [ Source:Any Timeout (Seconds):30 Continue Task // I am getting the location, timeout is 30 seconds, adjust it accordingly.                                 Immediately:Off Keep Tracking:Off ]                         A10: Secure Settings [ Configuration:Screen Dim // Now, this extension of the plugin Secure Settings, wakes your device so that you can type out the string on the WhatsApp app.                                 5 Seconds Package:com.intangibleobject.securesettings.plugin                                 Name:Secure Settings ]                         A11: Run Shell [ Command:input text // Now, I am using the shell script to type the text to the window, because the ‘:’ while not be typed from the Type task in Tasker.                                 LOCATION:maps.google.com/maps?q=%LOC Timeout (Seconds):0 Use Root:On // And also, this is way faster, but remember you need root for this, not for the other way of typing.                                 Store Result In: ]                         A12: Dpad [ Button:Right Repeat Times:1 ] // Focus the Send button                         A13: Dpad [ Button:Press Repeat Times:1 ] // And press it.                         A14: Dpad [ Button:Left Repeat Times:1 ] // Get back to the typing box.                         A15: Run Shell [ Command:input text LOCATION_ACCURACY:%LOCACC Timeout                                 (Seconds):0 Use Root:On Store Result In: ]                         A16: Dpad [ Button:Right Repeat Times:1 ]                         A17: Dpad [ Button:Press Repeat Times:1 ]                         A18: Dpad [ Button:Left Repeat Times:1 ]                         A19: Run Shell [ Command:input text BATTERY_LEVEL:%BATT% Timeout // I am adding Battery level in my case as well.                                 (Seconds):0 Use Root:On Store Result In: ]                         A20: Dpad [ Button:Right Repeat Times:1 ]                         A21: Dpad [ Button:Press Repeat Times:1 ]                         A22: Variable Set [ Name:%WHATSAPP_LASTREQ To:%WHATSAPP_CURRREQ Do // And now, we say, request is done.                                 Maths:Off Append:Off ]                         A23: Button [ Button:Back ] // I am exiting the WhatsApp nicely and not killing it. If you are the murderer kind, kill it, just know, you don’t have any place in the heaven.                         A24: Button [ Button:Back ]                         A25: Notify Cancel [ Title: Warn Not Exist:Off ] // Remove the permanent notification.                         A26: Notify [ Title:WhatsApp location request Text:Location sent // Make a temporary notification, and say, location is sent.                                 successfully. Icon:<icon> Number:0 Permanent:Off Priority:3 ]                                                         A27: Secure Settings [ Configuration:GPS Disabled // Disable all the horrible things we turned on earlier.                                 Package:com.intangibleobject.securesettings.plugin Name:Secure                                 Settings ]                         A28: Secure Settings [ Configuration:Pattern Lock Enabled                                 Package:com.intangibleobject.securesettings.plugin Name:Secure                                 Settings ]                         A29: Secure Settings [ Configuration:Keyguard Enabled                                 Package:com.intangibleobject.securesettings.plugin Name:Secure                                 Settings ]                 A30: End If         A31: End If Download this Task from here: http://db.tt/9vRmbhyb That’s it in the above small example – you can read/write messages from/to WhatsApp app. I am using n7000-cm9.1-cwr6. Oh yea, and if you are having the Talkback auto enabled for Chrome browser, you need to turn Off the Web scripts to run. Tasker is amazing, I have automated a lot of tasks using this tool. I will share a few none generic ones with you in my coming post here.

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• Grow Your Business with Security

  - by Darin Pendergraft

  Author: Kevin Moulton Kevin Moulton has been in the security space for more than 25 years, and with Oracle for 7 years. He manages the East EnterpriseSecurity Sales Consulting Team. He is also a Distinguished Toastmaster. Follow Kevin on Twitter at twitter.com/kevin_moulton, where he sometimes tweets about security, but might also tweet about running, beer, food, baseball, football, good books, or whatever else grabs his attention. Kevin will be a regular contributor to this blog so stay tuned for more posts from him. It happened again! There I was, reading something interesting online, and realizing that a friend might find it interesting too. I clicked on the little email link, thinking that I could easily forward this to my friend, but no! Instead, a new screen popped up where I was asked to create an account. I was expected to create a User ID and password, not to mention providing some personally identifiable information, just for the privilege of helping that website spread their word. Of course, I didn’t want to have to remember a new account and password, I didn’t want to provide the requisite information, and I didn’t want to waste my time. I gave up, closed the web page, and moved on to something else. I was left with a bad taste in my mouth, and my friend might never find her way to this interesting website. If you were this content provider, would this be the outcome you were looking for? A few days later, I had a similar experience, but this one went a little differently. I was surfing the web, when I happened upon some little chotcke that I just had to have. I added it to my cart. When I went to buy the item, I was again brought to a page to create account. Groan! But wait! On this page, I also had the option to sign in with my OpenID account, my Facebook account, my Yahoo account, or my Google Account. I have all of those! No new account to create, no new password to remember, and no personally identifiable information to be given to someone else (I’ve already given it all to those other guys, after all). In this case, the vendor was easy to deal with, and I happily completed the transaction. That pleasant experience will bring me back again. This is where security can grow your business. It’s a differentiator. You’ve got to have a presence on the web, and that presence has to take into account all the smart phones everyone’s carrying, and the tablets that took over cyber Monday this year. If you are a company that a customer can deal with securely, and do so easily, then you are a company customers will come back to again and again. I recently had a need to open a new bank account. Every bank has a web presence now, but they are certainly not all the same. I wanted one that I could deal with easily using my laptop, but I also wanted 2-factor authentication in case I had to login from a shared machine, and I wanted an app for my iPad. I found a bank with all three, and that’s who I am doing business with. Let’s say, for example, that I’m in a regular Texas Hold-em game on Friday nights, so I move a couple of hundred bucks from checking to savings on Friday afternoons. I move a similar amount each week and I do it from the same machine. The bank trusts me, and they trust my machine. Most importantly, they trust my behavior. This is adaptive authentication. There should be no reason for my bank to make this transaction difficult for me. Now let's say that I login from a Starbucks in Uzbekistan, and I transfer $2,500. What should my bank do now? Should they stop the transaction? Should they call my home number? (My former bank did exactly this once when I was taking money out of an ATM on a business trip, when I had provided my cell phone number as my primary contact. When I asked them why they called my home number rather than my cell, they told me that their “policy” is to call the home number. If I'm on the road, what exactly is the use of trying to reach me at home to verify my transaction?) But, back to Uzbekistan… Should my bank assume that I am happily at home in New Jersey, and someone is trying to hack into my account? Perhaps they think they are protecting me, but I wouldn’t be very happy if I happened to be traveling on business in Central Asia. What if my bank were to automatically analyze my behavior and calculate a risk score? Clearly, this scenario would be outside of my typical behavior, so my risk score would necessitate something more than a simple login and password. Perhaps, in this case, a one-time password to my cell phone would prove that this is not just some hacker half way around the world. But, what if you're not a bank? Do you need this level of security? If you want to be a business that is easy to deal with while also protecting your customers, then of course you do. You want your customers to trust you, but you also want them to enjoy doing business with you. Make it easy for them to do business with you, and they’ll come back, and perhaps even Tweet about it, or Like you, and then their friends will follow. How can Oracle help? Oracle has the technology and expertise to help you to grown your business with security. Oracle Adaptive Access Manager will help you to prevent fraud while making it easier for your customers to do business with you by providing the risk analysis I discussed above, step-up authentication, and much more. Oracle Mobile and Social Access Service will help you to secure mobile access to applications by expanding on your existing back-end identity management infrastructure, and allowing your customers to transact business with you using the social media accounts they already know. You also have device fingerprinting and metrics to help you to grow your business securely. Security is not just a cost anymore. It’s a way to set your business apart. With Oracle’s help, you can be the business that everyone’s tweeting about. Image courtesy of Flickr user shareski

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• Guide to MySQL & NoSQL, Webinar Q&A

  - by Mat Keep

  0 0 1 959 5469 Homework 45 12 6416 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} Yesterday we ran a webinar discussing the demands of next generation web services and how blending the best of relational and NoSQL technologies enables developers and architects to deliver the agility, performance and availability needed to be successful. Attendees posted a number of great questions to the MySQL developers, serving to provide additional insights into areas like auto-sharding and cross-shard JOINs, replication, performance, client libraries, etc. So I thought it would be useful to post those below, for the benefit of those unable to attend the webinar. Before getting to the Q&A, there are a couple of other resources that maybe useful to those looking at NoSQL capabilities within MySQL: - On-Demand webinar (coming soon!) - Slides used during the webinar - Guide to MySQL and NoSQL whitepaper  - MySQL Cluster demo, including NoSQL interfaces, auto-sharing, high availability, etc.  So here is the Q&A from the event  Q. Where does MySQL Cluster fit in to the CAP theorem? A. MySQL Cluster is flexible. A single Cluster will prefer consistency over availability in the presence of network partitions. A pair of Clusters can be configured to prefer availability over consistency. A full explanation can be found on the MySQL Cluster & CAP Theorem blog post.  Q. Can you configure the number of replicas? (the slide used a replication factor of 1) Yes. A cluster is configured by an .ini file. The option NoOfReplicas sets the number of originals and replicas: 1 = no data redundancy, 2 = one copy etc. Usually there's no benefit in setting it >2. Q. Interestingly most (if not all) of the NoSQL databases recommend having 3 copies of data (the replication factor).    Yes, with configurable quorum based Reads and writes. MySQL Cluster does not need a quorum of replicas online to provide service. Systems that require a quorum need > 2 replicas to be able to tolerate a single failure. Additionally, many NoSQL systems take liberal inspiration from the original GFS paper which described a 3 replica configuration. MySQL Cluster avoids the need for a quorum by using a lightweight arbitrator. You can configure more than 2 replicas, but this is a tradeoff between incrementally improved availability, and linearly increased cost. Q. Can you have cross node group JOINS? Wouldn't that run into the risk of flooding the network? MySQL Cluster 7.2 supports cross nodegroup joins. A full cross-join can require a large amount of data transfer, which may bottleneck on network bandwidth. However, for more selective joins, typically seen with OLTP and light analytic applications, cross node-group joins give a great performance boost and network bandwidth saving over having the MySQL Server perform the join. Q. Are the details of the benchmark available anywhere? According to my calculations it results in approx. 350k ops/sec per processor which is the largest number I've seen lately The details are linked from Mikael Ronstrom's blog The benchmark uses a benchmarking tool we call flexAsynch which runs parallel asynchronous transactions. It involved 100 byte reads, of 25 columns each. Regarding the per-processor ops/s, MySQL Cluster is particularly efficient in terms of throughput/node. It uses lock-free minimal copy message passing internally, and maximizes ID cache reuse. Note also that these are in-memory tables, there is no need to read anything from disk. Q. Is access control (like table) planned to be supported for NoSQL access mode? Currently we have not seen much need for full SQL-like access control (which has always been overkill for web apps and telco apps). So we have no plans, though especially with memcached it is certainly possible to turn-on connection-level access control. But specifically table level controls are not planned. Q. How is the performance of memcached APi with MySQL against memcached+MySQL or any other Object Cache like Ecache with MySQL DB? With the memcache API we generally see a memcached response in less than 1 ms. and a small cluster with one memcached server can handle tens of thousands of operations per second. Q. Can .NET can access MemcachedAPI? Yes, just use a .Net memcache client such as the enyim or BeIT memcache libraries. Q. Is the row level locking applicable when you update a column through memcached API? An update that comes through memcached uses a row lock and then releases it immediately. Memcached operations like "INCREMENT" are actually pushed down to the data nodes. In most cases the locks are not even held long enough for a network round trip. Q. Has anyone published an example using something like PHP? I am assuming that you just use the PHP memcached extension to hook into the memcached API. Is that correct? Not that I'm aware of but absolutely you can use it with php or any of the other drivers Q. For beginner we need more examples. Take a look here for a fully worked example Q. Can I access MySQL using Cobol (Open Cobol) or C and if so where can I find the coding libraries etc? A. There is a cobol implementation that works well with MySQL, but I do not think it is Open Cobol. Also there is a MySQL C client library that is a standard part of every mysql distribution Q. Is there a place to go to find help when testing and/implementing the NoSQL access? If using Cluster then you can use the [email protected] alias or post on the MySQL Cluster forum Q. Are there any white papers on this?  Yes - there is more detail in the MySQL Guide to NoSQL whitepaper If you have further questions, please don’t hesitate to use the comments below!

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• Rebuilding CoasterBuzz, Part III: The architecture using the "Web stack of love"

  - by Jeff

  This is the third post in a series about rebuilding one of my Web sites, which has been around for 12 years. I hope to relaunch in the next month or two. More: Part I: Evolution, and death to WCF Part II: Hot data objects I finally hit a point in the re-do of CoasterBuzz where I feel like the major pieces are in place... rewritten, ported and what not, so that I can focus now on front-end design and more interesting creative problems. I've been asked on more than one occasion (OK, just twice) what's going on under the covers, so I figure this might be a good time to explain the overall architecture. As it turns out, I'm using a whole lof of the "Web stack of love," as Scott Hanselman likes to refer to it. Oh that Hanselman. First off, at the center of it all, is BizTalk. Just kidding. That's "enterprise architecture" humor, where every discussion starts with how they'll use BizTalk. Here are the bigger moving parts: It's fairly straight forward. A common library lives in a number of Web apps, all of which are (or will be) powered by ASP.NET MVC 4. They all talk to the same database. There is the main Web site, which also has the endpoint for the Silverlight-based Feed app. The cstr.bz site handles redirects, which are generated when news items are published and sent to Twitter. Facebook publishing is handled via the RSS Graffiti Facebook app. The API site handles requests from the Windows Phone app. The main site depends very heavily on POP Forums, the open source, MVC-based forum I maintain. It serves a number of functions, primarily handling users. These user objects serve in non-forum roles to handle things like news and database contributions, maintaining track records (coaster nerd for "list of rides I've been on") and, perhaps most importantly, paid club memberships. Before I get into more specifics, note that the "glue" for everything is Ninject, the dependency injection framework. I actually prefer StructureMap these days, but I started with Ninject in POP Forums a long time ago. POP Forums has a static class, PopForumsActivation, that new's up an instance of the container, and you can call it from where ever. The downside is that the forums require Ninject in your MVC app as the default dependency resolver. At some point, I'll decouple it, but for now it's not in the way. In the general sense, the entire set of apps follow a repository-service-controller-view pattern. Repos just do data access, service classes do business logic, controllers compose and route, views view. The forum also provides Scoring Game functionality. The Scoring Game is a reasonably abstract framework to award users points based on certain actions, and then award achievements when a certain number of point events happen. For example, the forum already awards a point when someone plus-one's a post you made. You can set up an achievement that says, "Give the user an award when they've had 100 posts plus'd." It also does zero-point entries into the ledger, so if you make a post, you could award an achievement based on 100 posts made. Wiring in the scoring game to CoasterBuzz functionality is just a matter of going to the Ninject container and getting an instance of the event publisher, and passing it events. Forum adapters were introduced into POP Forums a few versions ago, and they can intercept the model generated for forum topic lists and threads and designate an alternate view. These are used to make the "Day in Pictures" forum, where users can upload photos as frame-by-frame photo threads. Another adapter adds an association UI, so users can associate specific amusement parks with their trip report posts. The Silverlight-based Feed app talks to a simple JSON endpoint in the main app. This uses an underlying library I wrote ages ago, simply called Feeds, that aggregates event information. You inherit from a base class that creates instances of a publisher interface, and then use that class to send it an event type and any number of data fields. Feeds has two publishers: One is to the database, and that's used for the endpoint that talks to the Silverlight app. The second publisher publishes to Twitter, if the event is of the type "news." The wiring is a little strange, because for the new posts and topics events, I'm actually pulling out the forum repository classes from the Ninject container and replacing them with overridden methods to publish. I should probably be doing this at the service class level, but whatever. It's my mess. cstr.bz doesn't do anything interesting. It looks up the path, and if it has a match, does a 301 redirect to the long URL. The API site just serves up JSON for the Windows Phone app. The Windows Phone app is Silverlight, of course, and there isn't much to it. It does use the control toolkit, but beyond that, it relies on a simple class that creates a Webclient and calls the server for JSON to deserialize. The same class is now used by the Feed app, which used to use WCF. Simple is better. Data access in POP Forums is all straight SQL, because a lot of it was ported from the ASP.NET version. Most CoasterBuzz data access is handled by the Entity Framework, using the code-first model. The context class in this case does a lot of work to make sure that the table and key mapping works, since much of it breaks from the normal conventions of EF. One of the more powerful things you can do with EF, once you understand the little gotchas, is split tables by row into different entities. For example, a roller coaster photo has everything in the same row, including the metadata, the thumbnail bytes and the image itself. Obviously, if you want to get a list of photos to iterate over in a view, you don't want to get the image data. The use of navigation properties makes it easier to get just what you want. The front end includes Razor views in MVC, and jQuery is used for client-side goodness. I'm also using jQuery UI in a few places, for tabs, a dialog box and autocomplete. I'm also, tentatively, using jQuery Mobile. I've already ported most forum views to Mobile, but they need some work as v1.1 isn't finished yet. I'm not sure if I'll ship CoasterBuzz with mobile views or not yet. It's on the radar, but not something in my delivery criteria. That covers all of the big frameworks in play. Next time I hope to talk more about the front-end experience, which to me is where most of the fun is these days. Hoping to launch in the next month or two. Getting tired of looking at the old site!

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• Testing Workflows &ndash; Test-After

  - by Timothy Klenke

  Originally posted on: http://geekswithblogs.net/TimothyK/archive/2014/05/30/testing-workflows-ndash-test-after.aspxIn this post I’m going to outline a few common methods that can be used to increase the coverage of of your test suite.  This won’t be yet another post on why you should be doing testing; there are plenty of those types of posts already out there.  Assuming you know you should be testing, then comes the problem of how do I actual fit that into my day job.  When the opportunity to automate testing comes do you take it, or do you even recognize it? There are a lot of ways (workflows) to go about creating automated tests, just like there are many workflows to writing a program.  When writing a program you can do it from a top-down approach where you write the main skeleton of the algorithm and call out to dummy stub functions, or a bottom-up approach where the low level functionality is fully implement before it is quickly wired together at the end.  Both approaches are perfectly valid under certain contexts. Each approach you are skilled at applying is another tool in your tool belt.  The more vectors of attack you have on a problem – the better.  So here is a short, incomplete list of some of the workflows that can be applied to increasing the amount of automation in your testing and level of quality in general.  Think of each workflow as an opportunity that is available for you to take. Test workflows basically fall into 2 categories:  test first or test after.  Test first is the best approach.  However, this post isn’t about the one and only best approach.  I want to focus more on the lesser known, less ideal approaches that still provide an opportunity for adding tests.  In this post I’ll enumerate some test-after workflows.  In my next post I’ll cover test-first. Bug Reporting When someone calls you up or forwards you a email with a vague description of a bug its usually standard procedure to create or verify a reproduction plan for the bug via manual testing and log that in a bug tracking system.  This can be problematic.  Often reproduction plans when written down might skip a step that seemed obvious to the tester at the time or they might be missing some crucial environment setting. Instead of data entry into a bug tracking system, try opening up the test project and adding a failing unit test to prove the bug.  The test project guarantees that all aspects of the environment are setup properly and no steps are missing.  The language in the test project is much more precise than the English that goes into a bug tracking system. This workflow can easily be extended for Enhancement Requests as well as Bug Reporting. Exploratory Testing Exploratory testing comes in when you aren’t sure how the system will behave in a new scenario.  The scenario wasn’t planned for in the initial system requirements and there isn’t an existing test for it.  By definition the system behaviour is “undefined”. So write a new unit test to define that behaviour.  Add assertions to the tests to confirm your assumptions.  The new test becomes part of the living system specification that is kept up to date with the test suite. Examples This workflow is especially good when developing APIs.  When you are finally done your production API then comes the job of writing documentation on how to consume the API.  Good documentation will also include code examples.  Don’t let these code examples merely exist in some accompanying manual; implement them in a test suite. Example tests and documentation do not have to be created after the production API is complete.  It is best to write the example code (tests) as you go just before the production code. Smoke Tests Every system has a typical use case.  This represents the basic, core functionality of the system.  If this fails after an upgrade the end users will be hosed and they will be scratching their heads as to how it could be possible that an update got released with this core functionality broken. The tests for this core functionality are referred to as “smoke tests”.  It is a good idea to have them automated and run with each build in order to avoid extreme embarrassment and angry customers. Coverage Analysis Code coverage analysis is a tool that reports how much of the production code base is exercised by the test suite.  In Visual Studio this can be found under the Test main menu item. The tool will report a total number for the code coverage, which can be anywhere between 0 and 100%.  Coverage Analysis shouldn’t be used strictly for numbers reporting.  Companies shouldn’t set minimum coverage targets that mandate that all projects must have at least 80% or 100% test coverage.  These arbitrary requirements just invite gaming of the coverage analysis, which makes the numbers useless. The analysis tool will break down the coverage by the various classes and methods in projects.  Instead of focusing on the total number, drill down into this view and see which classes have high or low coverage.  It you are surprised by a low number on a class this is an opportunity to add tests. When drilling through the classes there will be generally two types of reaction to a surprising low test coverage number.  The first reaction type is a recognition that there is low hanging fruit to be picked.  There may be some classes or methods that aren’t being tested, which could easy be.  The other reaction type is “OMG”.  This were you find a critical piece of code that isn’t under test.  In both cases, go and add the missing tests. Test Refactoring The general theme of this post up to this point has been how to add more and more tests to a test suite.  I’ll step back from that a bit and remind that every line of code is a liability.  Each line of code has to be read and maintained, which costs money.  This is true regardless whether the code is production code or test code. Remember that the primary goal of the test suite is that it be easy to read so that people can easily determine the specifications of the system.  Make sure that adding more and more tests doesn’t interfere with this primary goal. Perform code reviews on the test suite as often as on production code.  Hold the test code up to the same high readability standards as the production code.  If the tests are hard to read then change them.  Look to remove duplication.  Duplicate setup code between two or more test methods that can be moved to a shared function.  Entire test methods can be removed if it is found that the scenario it tests is covered by other tests.  Its OK to delete a test that isn’t pulling its own weight anymore. Remember to only start refactoring when all the test are green.  Don’t refactor the tests and the production code at the same time.  An automated test suite can be thought of as a double entry book keeping system.  The unchanging, passing production code serves as the tests for the test suite while refactoring the tests. As with all refactoring, it is best to fit this into your regular work rather than asking for time later to get it done.  Fit this into the standard red-green-refactor cycle.  The refactor step no only applies to production code but also the tests, but not at the same time.  Perhaps the cycle should be called red-green-refactor production-refactor tests (not quite as catchy).   That about covers most of the test-after workflows I can think of.  In my next post I’ll get into test-first workflows.

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• flex and bison: wrong output

  - by user2972227

  I am doing a homework using flex and bison to make a complex number calculator. But my program cannot give a correct output. .lex file: %option noyywrap %{ #include<stdio.h> #include<stdlib.h> #include "complex_cal.h" #define YYSTYPE complex #include "complex_cal.tab.h" void RmWs(char* str); %} /* Add your Flex definitions here */ /* Some definitions are already provided to you*/ ws [ \t]+ digits [0-9] number (0|[1-9]+{digits}*)\.?{digits}* im [i] complexnum {ws}*[-]*{ws}*{number}{ws}*[+|-]{ws}*{number}{ws}*{im}{ws}* op [-+*/()] %% {complexnum} {RmWs(yytext); sscanf(yytext,"%lf %lf",&(yylval.real),&(yylval.img)); return CNUMBER;} {ws} /**/ {op} return *yytext; %% /* function provided to student to remove */ /* all the whitespaces from a string. */ void RmWs(char* str){ int i=0,j=0; char temp[strlen(str)+1]; strcpy(temp,str); while (temp[i]!='\0'){ while (temp[i]==' '){i++;} str[j]=temp[i]; i++; j++; } str[j]='\0'; } .y file: %{ #include <stdio.h> #include <stdlib.h> #include "complex_cal.h" /* prototypes of the provided functions */ complex complex_add (complex, complex); complex complex_sub (complex, complex); complex complex_mul (complex, complex); complex complex_div (complex, complex); /* prototypes of the provided functions */ int yylex(void); int yyerror(const char*); %} %token CNUMBER %left '+' '-' %left '*' '/' %nonassoc '(' ')' %% /* start: Add your grammar rules and actions here */ complexexp: complexexp '+' complexexpmultidiv {$$=complex_add($1, $3);} | complexexp '-' complexexpmultidiv {$$=complex_sub($1, $3);} | complexexpmultidiv {$$.real=$1.real;$$.img=$1.img;} ; complexexpmultidiv: complexexpmultidiv '*' complexsimple {$$=complex_mul($1, $3);} | complexexpmultidiv '/' complexsimple {$$=complex_div($1, $3);} | complexsimple {$$.real=$1.real;$$.img=$1.img;} ; complexsimple: '(' complexexp ')' {$$.real=$2.real;$$.img=$2.img;} | '(' CNUMBER ')' {$$.real=$2.real;$$.img=$2.img;} ; /* end: Add your grammar rules and actions here */ %% int main(){ return yyparse(); } int yyerror(const char* s){ printf("%s\n", s); return 0; } /* function provided to do complex addition */ /* input : complex numbers c1, c2 */ /* output: nothing */ /* side effect : none */ /* return value: result of addition in c3 */ complex complex_add (complex c1, complex c2){ /* c1 + c2 */ complex c3; c3.real = c1.real + c2.real; c3.img = c1.img + c2.img; return c3; } /* function provided to do complex subtraction */ /* input : complex numbers c1, c2 */ /* output: nothing */ /* side effect : none */ /* return value: result of subtraction in c3 */ complex complex_sub (complex c1, complex c2){ /* c1 - c2 */ complex c3; c3.real = c1.real - c2.real; c3.img = c1.img - c2.img; return c3; } /* function provided to do complex multiplication */ /* input : complex numbers c1, c2 */ /* output: nothing */ /* side effect : none */ /* return value: result of multiplication in c3 */ complex complex_mul (complex c1, complex c2){ /* c1 * c2 */ complex c3; c3.real = c1.real*c2.real - c1.img*c2.img; c3.img = c1.img*c2.real + c1.real*c2.img; return c3; } /* function provided to do complex division */ /* input : complex numbers c1, c2 */ /* output: nothing */ /* side effect : none */ /* return value: result of c1/c2 in c3 */ complex complex_div (complex c1, complex c2){ /* c1 / c2 (i.e. c1 divided by c2 ) */ complex c3; double d; /*divisor calculation using the conjugate of c2*/ d = c2.real*c2.real + c2.img*c2.img; c3.real = (c1.real*c2.real + c1.img*c2.img)/d; c3.img = (c1.img*c2.real - c1.real*c2.img)/d; return c3; } .h file: #include <string.h> /* struct for holding a complex number */ typedef struct { double real; double img; } complex; /* define the return type of FLEX */ #define YYSTYPE complex Script for compiling the file: bison -d -v complex_cal.y flex -ocomplex_cal.lex.yy.c complex_cal.lex gcc -o complex_cal complex_cal.lex.yy.c complex_cal.tab.c ./complex_cal Some correct sample run of the program: input:(5+6i)*(6+1i) output:24.000000+41.000000i input:(7+8i)/(-3-4i)*(5+7i) output:-11.720000-14.040000i input:(7+8i)/((-3-4i)*(5+7i)) output:-0.128108+0.211351i But when I run this program, the program only give an output which is identical to my input. For example, when I input (5+6i)(6+1i), it just gives (5+6i)(6+1i). Even if I input any other things, for example, input "abc" it just gives "abc" and is not syntax error. I don't know where the problem is and I hope to know how to solve it.

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• Configuring Oracle HTTP Server 12c for WebLogic Server Domain

  - by Emin Askerov

  Oracle HTTP Server (OHS) 12c 12.1.2 which was released in July 2013 as a part of Oracle Web Tier 12c is the web server component of Oracle Fusion Middleware. In essence this is Apache HTTP Server 2.2.22 (with critical bug fixes from higher versions) which includes modules developed specifically by Oracle. It provides a listener functionality for Oracle WebLogic Server and the framework for hosting static pages, dynamic pages, and applications over the Web. OHS can be easily managed by Weblogic Management Framework, a set of tools which provides administrative capabilities (start, stop, lifecycle operations, etc.) for Oracle Fusion Middleware products. In other words all tools which are familiar to us (Node Manager, WLST, Administration Console, Fusion Middleware Control etc.) presented as a part of Weblogic Management Framework and using for managing Java and System Components both for Weblogic Server and Standalone Domain types. You can familiarize yourself with these terms using related documentation: 1. Introduction to Oracle HTTP Server: http://docs.oracle.com/middleware/1212/webtier/index.html 2. Weblogic Management Framework: http://docs.oracle.com/middleware/1212/core/ASCON/terminology.htm#ASCON11260 In the given post I would like to cover rather simple use case how to configure OHS as web proxy in Weblogic Cluster environment. For example, we have existing Weblogic Domain where some managed servers have been joined to cluster and host business applications. We need to configure web proxy component which will act as entry point, load balancer for our cluster for user requests. Of course, we could install old good Apache HTTP Server and configure mod_wl plugin. However this solution not optimal from manageability perspective: we need to install Apache, install additional plugin then configure it by editing configuration file which is not really convenient for FMW Administrators and often increase time of performing of simple administrative task. Alternatively, we could use OHS as System Component within Weblogic Domain and use full power of Weblogic Management Framework in order to configure, manage and monitor it! I like this idea! What about you? I hope after reading this post you will agree with me. First of all it is necessary to download OHS binaries. You can use this link for downloading: http://www.oracle.com/technetwork/java/webtier/downloads/index2-303202.html As we will use Fusion Middleware Control for managing OHS instances it is necessary to extend your domain with Enterprise Manager and Oracle ADF and JRF templates. This is not topic for focusing in this post, but you could get more information from documentation or one of my previous posts: http://docs.oracle.com/middleware/1212/wls/WLDTR/fmw_templates.htm#sthref64 https://blogs.oracle.com/imc/entry/the_specifics_of_adf_12c Note: you should have properly configured Node Manager utility for managing OHS instances Let’s consider configuration process step by step: 1. Shut down all Weblogic instances of existing domain including Admin Server; 2. Install Oracle HTTP Server. You should use your Fusion Middleware Home Path (e.g. /u01/Oracle/FMW12) for Installation Location and select Colocated HTTP Server option as Installation Type. I will not focus on this topic in this post. All information related to OHS installation you could find here: http://docs.oracle.com/middleware/1212/webtier/WTINS/install_gui.htm#i1082009 3. Next we need to extend our existing domain with OHS component. In order to do this you should do the following: a. Run Fusion Middleware Configuration Wizard (ORACLE_HOME/oracle_common/common/bin/config.sh); b. On the step 1 select Update an existing domain option and point your Fusion Middleware Home Path; c. On the step 2 check Oracle HTTP Server, Oracle Enterprise Manager Plugin for WEBTIER templates; d. Go through other steps without any changes and finish configuration process. 4. Start Admin Server and all managed servers related to your cluster 5. Log in to Enterprise Manager FMW Control using http://<hostname>:<port>/em URL 6. Now we will create OHS instance within our Weblogic Domain Infrastructure. Navigate to Weblogic Domain -> Administration -> Create/Delete OHS menu item; 7. Enter to edit mode, clicking Changes -> Lock&Edit menu item; 8. Create new OHS instance clicking Create button; 9. Define Instance Name (e.g. DevOSH) and Machine parameters; 10. Now we need to define listen port. By default OHS will use 7777 port number for income HTTP requests. We could change it to any free port number we would like to use. In order to do it, right click on our created OHS instance (left hand panel) and navigate to Administration -> Port Configuration; 11. Click on record with port number 7777 and then click Edit button; 12. Change port number value (in our case this will be 8080) and then click OK button; 13. Now we need to edit mod_wl_ohs configuration in order to enable OHS to act as proxy for WebLogic Server Instances/Cluster; 14. In order to do it right click on our created OHS instance (left panel) and navigate to Administration -> mod_wl_ohs Configuration; a. In Weblogic Cluster you should enter cluster address (define <host:port> for all managed servers which participated in cluster), e.g: 192.168.56.2:7004,192.168.56.2:7005 b. Define Weblogic Port parameter at which the Oracle WebLogic Server host is listening for connection requests from the module (or from other servers); c. Check Dynamic Server List option. This will dynamically update cluster list for every request; d. In the Location table define list of endpoint locations which you would like to process. In order to do this click Add Row button and define Location, Weblogic Cluster, Path Trim and Path Prefix parameters (if required); e. Click Apply button in order to save changes. 15. Activate changes clicking Changes ? Activate Changes menu item; 16. Finally we will start configured OHS instance. Right click on OHS instance tree item under Web Tier folder, select Control -> Start Up menu item; 17. Ensure that OHS instance up and running and then test your environment. Run deployed application to your Weblogic Cluster accessing via OHS web proxy; Normal 0 false false false RU X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;}

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• DTracing TCP congestion control

  - by user12820842

  In a previous post, I showed how we can use DTrace to probe TCP receive and send window events. TCP receive and send windows are in effect both about flow-controlling how much data can be received - the receive window reflects how much data the local TCP is prepared to receive, while the send window simply reflects the size of the receive window of the peer TCP. Both then represent flow control as imposed by the receiver. However, consider that without the sender imposing flow control, and a slow link to a peer, TCP will simply fill up it's window with sent segments. Dealing with multiple TCP implementations filling their peer TCP's receive windows in this manner, busy intermediate routers may drop some of these segments, leading to timeout and retransmission, which may again lead to drops. This is termed congestion, and TCP has multiple congestion control strategies. We can see that in this example, we need to have some way of adjusting how much data we send depending on how quickly we receive acknowledgement - if we get ACKs quickly, we can safely send more segments, but if acknowledgements come slowly, we should proceed with more caution. More generally, we need to implement flow control on the send side also. Slow Start and Congestion Avoidance From RFC2581, let's examine the relevant variables: "The congestion window (cwnd) is a sender-side limit on the amount of data the sender can transmit into the network before receiving an acknowledgment (ACK). Another state variable, the slow start threshold (ssthresh), is used to determine whether the slow start or congestion avoidance algorithm is used to control data transmission" Slow start is used to probe the network's ability to handle transmission bursts both when a connection is first created and when retransmission timers fire. The latter case is important, as the fact that we have effectively lost TCP data acts as a motivator for re-probing how much data the network can handle from the sending TCP. The congestion window (cwnd) is initialized to a relatively small value, generally a low multiple of the sending maximum segment size. When slow start kicks in, we will only send that number of bytes before waiting for acknowledgement. When acknowledgements are received, the congestion window is increased in size until cwnd reaches the slow start threshold ssthresh value. For most congestion control algorithms the window increases exponentially under slow start, assuming we receive acknowledgements. We send 1 segment, receive an ACK, increase the cwnd by 1 MSS to 2*MSS, send 2 segments, receive 2 ACKs, increase the cwnd by 2*MSS to 4*MSS, send 4 segments etc. When the congestion window exceeds the slow start threshold, congestion avoidance is used instead of slow start. During congestion avoidance, the congestion window is generally updated by one MSS for each round-trip-time as opposed to each ACK, and so cwnd growth is linear instead of exponential (we may receive multiple ACKs within a single RTT). This continues until congestion is detected. If a retransmit timer fires, congestion is assumed and the ssthresh value is reset. It is reset to a fraction of the number of bytes outstanding (unacknowledged) in the network. At the same time the congestion window is reset to a single max segment size. Thus, we initiate slow start until we start receiving acknowledgements again, at which point we can eventually flip over to congestion avoidance when cwnd ssthresh. Congestion control algorithms differ most in how they handle the other indication of congestion - duplicate ACKs. A duplicate ACK is a strong indication that data has been lost, since they often come from a receiver explicitly asking for a retransmission. In some cases, a duplicate ACK may be generated at the receiver as a result of packets arriving out-of-order, so it is sensible to wait for multiple duplicate ACKs before assuming packet loss rather than out-of-order delivery. This is termed fast retransmit (i.e. retransmit without waiting for the retransmission timer to expire). Note that on Oracle Solaris 11, the congestion control method used can be customized. See here for more details. In general, 3 or more duplicate ACKs indicate packet loss and should trigger fast retransmit . It's best not to revert to slow start in this case, as the fact that the receiver knew it was missing data suggests it has received data with a higher sequence number, so we know traffic is still flowing. Falling back to slow start would be excessive therefore, so fast recovery is used instead. Observing slow start and congestion avoidance The following script counts TCP segments sent when under slow start (cwnd ssthresh). #!/usr/sbin/dtrace -s #pragma D option quiet tcp:::connect-request / start[args[1]-cs_cid] == 0/ { start[args[1]-cs_cid] = 1; } tcp:::send / start[args[1]-cs_cid] == 1 && args[3]-tcps_cwnd tcps_cwnd_ssthresh / { @c["Slow start", args[2]-ip_daddr, args[4]-tcp_dport] = count(); } tcp:::send / start[args[1]-cs_cid] == 1 && args[3]-tcps_cwnd args[3]-tcps_cwnd_ssthresh / { @c["Congestion avoidance", args[2]-ip_daddr, args[4]-tcp_dport] = count(); } As we can see the script only works on connections initiated since it is started (using the start[] associative array with the connection ID as index to set whether it's a new connection (start[cid] = 1). From there we simply differentiate send events where cwnd ssthresh (congestion avoidance). Here's the output taken when I accessed a YouTube video (where rport is 80) and from an FTP session where I put a large file onto a remote system. # dtrace -s tcp_slow_start.d ^C ALGORITHM RADDR RPORT #SEG Slow start 10.153.125.222 20 6 Slow start 138.3.237.7 80 14 Slow start 10.153.125.222 21 18 Congestion avoidance 10.153.125.222 20 1164 We see that in the case of the YouTube video, slow start was exclusively used. Most of the segments we sent in that case were likely ACKs. Compare this case - where 14 segments were sent using slow start - to the FTP case, where only 6 segments were sent before we switched to congestion avoidance for 1164 segments. In the case of the FTP session, the FTP data on port 20 was predominantly sent with congestion avoidance in operation, while the FTP session relied exclusively on slow start. For the default congestion control algorithm - "newreno" - on Solaris 11, slow start will increase the cwnd by 1 MSS for every acknowledgement received, and by 1 MSS for each RTT in congestion avoidance mode. Different pluggable congestion control algorithms operate slightly differently. For example "highspeed" will update the slow start cwnd by the number of bytes ACKed rather than the MSS. And to finish, here's a neat oneliner to visually display the distribution of congestion window values for all TCP connections to a given remote port using a quantization. In this example, only port 80 is in use and we see the majority of cwnd values for that port are in the 4096-8191 range. # dtrace -n 'tcp:::send { @q[args[4]-tcp_dport] = quantize(args[3]-tcps_cwnd); }' dtrace: description 'tcp:::send ' matched 10 probes ^C 80 value ------------- Distribution ------------- count -1 | 0 0 |@@@@@@ 5 1 | 0 2 | 0 4 | 0 8 | 0 16 | 0 32 | 0 64 | 0 128 | 0 256 | 0 512 | 0 1024 | 0 2048 |@@@@@@@@@ 8 4096 |@@@@@@@@@@@@@@@@@@@@@@@@@@ 23 8192 | 0

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• Benchmarking MySQL Replication with Multi-Threaded Slaves

  - by Mat Keep

  0 0 1 1145 6530 Homework 54 15 7660 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} The objective of this benchmark is to measure the performance improvement achieved when enabling the Multi-Threaded Slave enhancement delivered as a part MySQL 5.6. As the results demonstrate, Multi-Threaded Slaves delivers 5x higher replication performance based on a configuration with 10 databases/schemas. For real-world deployments, higher replication performance directly translates to: · Improved consistency of reads from slaves (i.e. reduced risk of reading "stale" data) · Reduced risk of data loss should the master fail before replicating all events in its binary log (binlog) The multi-threaded slave splits processing between worker threads based on schema, allowing updates to be applied in parallel, rather than sequentially. This delivers benefits to those workloads that isolate application data using databases - e.g. multi-tenant systems deployed in cloud environments. Multi-Threaded Slaves are just one of many enhancements to replication previewed as part of the MySQL 5.6 Development Release, which include: · Global Transaction Identifiers coupled with MySQL utilities for automatic failover / switchover and slave promotion · Crash Safe Slaves and Binlog · Optimized Row Based Replication · Replication Event Checksums · Time Delayed Replication These and many more are discussed in the “MySQL 5.6 Replication: Enabling the Next Generation of Web & Cloud Services” Developer Zone article  Back to the benchmark - details are as follows. Environment The test environment consisted of two Linux servers: · one running the replication master · one running the replication slave. Only the slave was involved in the actual measurements, and was based on the following configuration: - Hardware: Oracle Sun Fire X4170 M2 Server - CPU: 2 sockets, 6 cores with hyper-threading, 2930 MHz. - OS: 64-bit Oracle Enterprise Linux 6.1 - Memory: 48 GB Test Procedure Initial Setup: Two MySQL servers were started on two different hosts, configured as replication master and slave. 10 sysbench schemas were created, each with a single table: CREATE TABLE `sbtest` (    `id` int(10) unsigned NOT NULL AUTO_INCREMENT,    `k` int(10) unsigned NOT NULL DEFAULT '0',    `c` char(120) NOT NULL DEFAULT '',    `pad` char(60) NOT NULL DEFAULT '',    PRIMARY KEY (`id`),    KEY `k` (`k`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 10,000 rows were inserted in each of the 10 tables, for a total of 100,000 rows. When the inserts had replicated to the slave, the slave threads were stopped. The slave data directory was copied to a backup location and the slave threads position in the master binlog noted. 10 sysbench clients, each configured with 10 threads, were spawned at the same time to generate a random schema load against each of the 10 schemas on the master. Each sysbench client executed 10,000 "update key" statements: UPDATE sbtest set k=k+1 WHERE id = <random row> In total, this generated 100,000 update statements to later replicate during the test itself. Test Methodology: The number of slave workers to test with was configured using: SET GLOBAL slave_parallel_workers=<workers> Then the slave IO thread was started and the test waited for all the update queries to be copied over to the relay log on the slave. The benchmark clock was started and then the slave SQL thread was started. The test waited for the slave SQL thread to finish executing the 100k update queries, doing "select master_pos_wait()". When master_pos_wait() returned, the benchmark clock was stopped and the duration calculated. The calculated duration from the benchmark clock should be close to the time it took for the SQL thread to execute the 100,000 update queries. The 100k queries divided by this duration gave the benchmark metric, reported as Queries Per Second (QPS). Test Reset: The test-reset cycle was implemented as follows: · the slave was stopped · the slave data directory replaced with the previous backup · the slave restarted with the slave threads replication pointer repositioned to the point before the update queries in the binlog. The test could then be repeated with identical set of queries but a different number of slave worker threads, enabling a fair comparison. The Test-Reset cycle was repeated 3 times for 0-24 number of workers and the QPS metric calculated and averaged for each worker count. MySQL Configuration The relevant configuration settings used for MySQL are as follows: binlog-format=STATEMENT relay-log-info-repository=TABLE master-info-repository=TABLE As described in the test procedure, the slave_parallel_workers setting was modified as part of the test logic. The consequence of changing this setting is: 0 worker threads:    - current (i.e. single threaded) sequential mode    - 1 x IO thread and 1 x SQL thread    - SQL thread both reads and executes the events 1 worker thread:    - sequential mode    - 1 x IO thread, 1 x Coordinator SQL thread and 1 x Worker thread    - coordinator reads the event and hands it to the worker who executes 2+ worker threads:    - parallel execution    - 1 x IO thread, 1 x Coordinator SQL thread and 2+ Worker threads    - coordinator reads events and hands them to the workers who execute them Results Figure 1 below shows that Multi-Threaded Slaves deliver ~5x higher replication performance when configured with 10 worker threads, with the load evenly distributed across our 10 x schemas. This result is compared to the current replication implementation which is based on a single SQL thread only (i.e. zero worker threads). Figure 1: 5x Higher Performance with Multi-Threaded Slaves The following figure shows more detailed results, with QPS sampled and reported as the worker threads are incremented. The raw numbers behind this graph are reported in the Appendix section of this post. Figure 2: Detailed Results As the results above show, the configuration does not scale noticably from 5 to 9 worker threads. When configured with 10 worker threads however, scalability increases significantly. The conclusion therefore is that it is desirable to configure the same number of worker threads as schemas. Other conclusions from the results: · Running with 1 worker compared to zero workers just introduces overhead without the benefit of parallel execution. · As expected, having more workers than schemas adds no visible benefit. Aside from what is shown in the results above, testing also demonstrated that the following settings had a very positive effect on slave performance: relay-log-info-repository=TABLE master-info-repository=TABLE For 5+ workers, it was up to 2.3 times as fast to run with TABLE compared to FILE. Conclusion As the results demonstrate, Multi-Threaded Slaves deliver significant performance increases to MySQL replication when handling multiple schemas. This, and the other replication enhancements introduced in MySQL 5.6 are fully available for you to download and evaluate now from the MySQL Developer site (select Development Release tab). You can learn more about MySQL 5.6 from the documentation  Please don’t hesitate to comment on this or other replication blogs with feedback and questions. Appendix – Detailed Results

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• PHP + Code Igniter Timecode Calculation Logic Error

  - by Tim

  Hello everyone, I have what I suspect to be a logic problem with an algorithm I am using to work with Video timecode in PHP. All help is appreciated. The Objective Well basically I want to work with timecode and perform calculations For those not familiar with timecode it looks like this 01:10:58:12 or HH:MM:SS:FF 'AKA' HOURS:MINUTES:SECONDS:FRAMES I have used the script from HERE to help me with working with this format. The Problem Now can i just say that this script works!!! Timecode calculations (in this case additions) are being performed correctly. However this script continually throws the following errors, yet still produces the correct output when I try and do the following calculation 00:01:26:00 + 00:02:00:12 The errors from this calculation are shown below A PHP Error was encountered Severity: Notice Message: Undefined index: key Filename: staff/tools.php Line Number: 169 A PHP Error was encountered Severity: Notice Message: Undefined index: key Filename: staff/tools.php Line Number: 169 Line Number 169 is in the parseInput() function // feed it into the tc array $i=0; foreach ($tc AS $key=>$value) { if ( is_numeric($array["$i"]) ) { $tc["$key"]= $array["$i"]; if ($tc["$key"] < 10 && $tc["$key"] > 0 && strlen($tc['key'])==1 ) $tc["$key"]= "0".$tc["$key"]; } $i++; } return $tc; Now I should also mention that the number of times the above error is thrown depends on what I am calculating 00:00:00:00 + 00:00:00:00 returns no errors. 01:01:01:01 + 02:02:02:02 produces 8 of the above errors. For your reference, here is the code in it's entirety function add_cue_sheet_clips_process() { $sheetID = $_POST['sheet_id']; $clipName = $_POST['clip_name']; $tcIn = $_POST['tc_in']; $tcOut = $_POST['tc_out']; // string $input // returns an associative array of hours, minutes, seconds, and frames // function parseInput ($input) { // timecode should look something like hh:mm:ss;ff // allowed separators are : ; . , // values may be single or double digits // hours are least-significant -- 5.4 == 00:00:05;04 $tc= array("frames"=>"00", "seconds"=>"00", "minutes"=>"00", "hours"=>"00"); $punct= array(":", ";", ".", ","); // too big? too small? $input= trim($input); if (strlen($input)>11 || $input=="") { // invalid input, too long -- bzzt return $tc; } // normalize punctuation $input= str_replace( $punct, ":", $input); // blow it up and reverse it so frames come first $array= explode(":", $input); $array= array_reverse($array); // feed it into the tc array $i=0; foreach ($tc AS $key=>$value) { if ( is_numeric($array["$i"]) ) { $tc["$key"]= $array["$i"]; if ($tc["$key"] < 10 && $tc["$key"] > 0 && strlen($tc['key'])==1 ) $tc["$key"]= "0".$tc["$key"]; } $i++; } return $tc; } // array $tc // returns a float number of seconds // function tcToSec($tc) { $wholeseconds= ($tc['hours']*3600) + ($tc['minutes'] * 60) + ($tc['seconds']); $partseconds= ( $tc['frames'] / 25 ); $seconds= $wholeseconds + $partseconds; return $seconds; } // float $seconds // bool $subtract // returns a timecode array // function secToTc ($seconds=0, $subtract=0) { $tc= array("frames"=>"00", "seconds"=>"00", "minutes"=>"00", "hours"=>"00"); $partseconds= fmod($seconds, 1); $wholeseconds= $seconds - $partseconds; // frames if ($subtract==1) $tc['frames']= floor( $partseconds * 25 ); else $tc['frames']= floor( $partseconds * 25 ); // hours $tc['hours']= floor( $wholeseconds / 3600 ); $minsec= ($wholeseconds - ($tc['hours'] * 3600)); // minutes $tc['minutes']= floor( $minsec / 60 ); // seconds $tc['seconds']= ( $minsec - ($tc['minutes'] * 60) ); // padding foreach ( $tc AS $key=>$value ) { if ($value > 0 && $value < 10) $tc["$key"]= "0".$value; if ($value=="0") $tc["$key"]= "00"; } return $tc; } // array $tc // returns string of well-formed timecode // function tcToString (&$tc) { return $tc['hours'].":".$tc['minutes'].":".$tc['seconds'].";".$tc['frames']; } $timecodeIN = parseInput($tcIn); $timecodeOUT = parseInput($tcOut); // normalized inputs... $tc1 = tcToString($timecodeIN); $tc2 = tcToString($timecodeOUT); // get seconds $seconds1 = tcToSec($timecodeIN); $seconds2 = tcToSec($timecodeOUT); $result = $seconds1 + $seconds2; $timecode3 = secToTc($result, 0); $timecodeDUR = tcToString($timecode3); $clipArray = array('clip_name' => $clipName, 'tc_in' => $tcIn, 'tc_out' => $tcOut, 'tc_duration' => $timecodeDUR); $this->db->insert('tools_cue_sheets_clips', $clipArray); redirect('staff/tools/add_cue_sheet_clips/'.$sheetID); } I hope this is enough information for someone to help me get on top of this, I would be extremely greatful. Thanks, Tim

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