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  • Actionscript: How Can I Know When The Source Property Of An Image Is Completely Updated

    - by Joshua
    var I:Image=new Image(); I.source='C:\\Abc.png'; var H:int=I.height; H is always Zero! I am presuming this is because the image hasn't finished reading the png file off the disk yet. What event can I monitor to know when it's width and height will have the right values? The 'Complete' event only seems to work for DOWNLOADED images. The 'Render' event happens EVERY FRAME. The (undocumented?) 'sourceChanged', happens as soon as source changes, and has the same problem! What event do I watch that will let me know when the image's width and height properties will have valid values? Or is there some Synchronous version of I.source='xxx.png', that I don't know about? P.S. Yes, I know I shouldn't use "C:\" in an Air Program. This was just for illustrative purposes, so that you won't suggest I use "Complete", which never even seems to fire when the file indicated by source is local.

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  • Problem when compressing SWF in Linux with java.util.zip

    - by CaioToOn
    Hi! I've created a servlet that changes the binaries of a SWF file and output it to the user. The SWF is compressed by ZLIB by default. Then I inflate, change the binaries, deflate and output the result. Everything was running right on a Windows Server 2008 (also in 2003). Currently, we need change the server to Linux, and then, this servlet is somehow outputing a corrupted SWF File... what could be the problem? What intrigues me more is that there is no difference between the Windows and Linux servlet versions. Is there any undocumented linux specific behaviour for the java.util.zip package? My Windows Server is (where the servlet is working): Windows Server 2008 (6.0 - x86) Apache 2.2.11 Tomcat 6.0.16.0 Java JDK 1.6.0_12-b04 My CentOS Server is (where te servlet doesn't work) CentOS 5.4 (2.6.18-164.15.1.el5 - i386) Apache 2.2.3 Tomcat 6.0.16.0 Java JDK 1.6.0_12-b04 Any lead would be appreciated! Cheers, CaioToOn!

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  • Can anyone provide a good "idiot's guide" to creating an installer in VS2008 (C#) Pro?

    - by paxdiablo
    I have Visual C# 2008 Professional and have developed the first half of a C# application (console mode) with the second half in progress now (GUI). I'm looking for an easy path to creating an installer for it. What are the steps that need to be taken to produce a professional installer? There's a similar question here regarding the Express edition but I have Pro, and I would like as much as possible to stick with just the standard VS stuff (if you think you can convince me that a third party installer creator is much better than a VS-only solution, give it a shot, by all means). Keep in mind that I have no interest in upgrading to VS2010 yet, even if it's a hundred times easier to create an installer. That can come later, when the revenue starts rolling in :-) Also be aware that the GUI component of this application is a totally separate executable from the console part. The console part is a simple "open file 1, do some work on it, write file 2" type and the GUI is a fairly standard "open file, do some stuff" beast so there's no tricky or wildly undocumented behaviour happening. Basically, I'm looking for (at least) the following: professional looking installer. ability to specify where the application files go. changes to the registry to allow double-clicks on my file extension to open the GUI app with the file as an argument. needs to install everything required (my stuff, .Net if required, and so on).

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  • UIImagePickerController Crash after 5 to 7 pictures - again

    - by Sophtware
    OK, I know this one has been beaten to death on this forum, but I'm still having the memory problem and I have tried all the techniques on the web to get around this. I have an application that uses the UIImagePickerController to capture an image from the camera. I've tried both creating and destroying the controller for each picture, and keeping it around for the life of the app. Both are failing. The first way crashes the phone almost immediately. While the second, leaving the controller around, crashes the app after about 5 to 7 pictures. My original app used an undocumented API to get around this issue, but Apple rejected it because of this. I really need to get my app to the store. Does anyone have code showing how they got around the issue? I know there is a way because there are apps on the store using the camera, but I just can't seem to get it. Any help is greatly appreciated! I can post my code here too, if needed.

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  • android.intent.action.NOTIFICATION_REMOVE not available on all devices?

    - by Matt McMinn
    I've got a receiver set up in my android application to catch android.intent.action.NOTIFICATION_REMOVE intents. On my Evo, it works fine - when a notification is cleared from the notification bar, I catch that event and can run some code. I tried running this on a Samsung Moment though, and it is never caught. So now I'm trying to figure out why, and I can't seem to find anything on Google about this intent action - and I set this code up a few months ago, so I don't remember where I even found this action, it doesn't seem to be in the API. The evo is running 2.2, and the moment is running 2.1-update1, so I'm guessing that it's undocumented, and only available in 2.2. Is there any other way to catch an event that a notification has been cleared? Note that I'm not trying to cancel a notification that I put up, or trying to cancel another app's notification, just catch an event when a notification has been cleared. Here's my receiver in AndroidManafest.xml: <receiver android:name=".NotificationClearedReciever"> <intent-filter> <action android:name="android.intent.action.NOTIFICATION_REMOVE" /> </intent-filter> </receiver>

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  • My website keeps crashing IE, can't debug

    - by Ninja rhino
    I have a website that suddenly started to crash internet explorer. The website loads and starts executing javascript but somewhere in there the machinery explodes. I don't even get a script error, it just crashes. I've tried to manually step through every single line of js with the built in debugger but then of course the problem doesn't occur. If i choose to debug the application when it crashes i see the following message. Unhandled exception at 0x6c5dedf5 in iexplore.exe: 0xC0000005: Access violation reading location 0x00000090. The top 5 items in the call stack looks like this VGX.dll!6c5dedf5() [Frames below may be incorrect and/or missing, no symbols loaded for VGX.dll] VGX.dll!6c594d70() VGX.dll!6c594f63() VGX.dll!6c595350() VGX.dll!6c58f5e3() mshtml.dll!6f88dd17() VGX.dll seems to be part of the vml renderer and i am in fact using VML. I'm not suprised because i've had so many problems with vml, attributes has to be set in specific order, sometimes you cant set attributes when you have elements attached to the dom or vice versa (everything undocumented btw) but then the problems can usually be reproduced when debugging but not now :( The problem also occurs in no plugin-mode. Is there a better approach than trial and error to solve this? Edit: Adding a console outputting every suspect modification to the DOM made the problem only occur sometimes. (the console is also implemented in javascript on the same page, i'm able to see the output even after a crash as the window is still visible) Apparently it seems to be some kind of race condition. I managed to track it down even further, and it seems to occur when you remove an object from the DOM too quickly after it's just been added. (most likely only for vml-elements with some special attribute, didn't try further) And it can't be fixed by adding a dead loop in front of removeChild(pretty bad solution anyway), the page has to be rendered by the browser once after the addChild before you can call removeChild. sigh

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  • Areca 1280ml RAID6 volume set failed

    - by Richard
    Today we hit some kind of worst case scenario and are open to any kind of good ideas. Here is our problem: We are using several dedicated storage servers to host our virtual machines. Before I continue, here are the specs: Dedicated Server Machine Areca 1280ml RAID controller, Firmware 1.49 12x Samsung 1TB HDDs We configured one RAID6-set with 10 discs that contains one logical volume. We have two hot spares in the system. Today one HDD failed. This happens from time to time, so we replaced it. Upon rebuilding a second disc failed. Normally this is no fun. We stopped heavy IO-operations to ensure a stable RAID rebuild. Sadly the hot-spare disc failed while rebuilding and the whole thing stopped. Now we have the following situation: The controller says that the raid set is rebuilding The controller says that the volume failed It is a RAID 6 system and two discs failed, so the data has to be intact, but we cannot bring the volume online again to access the data. While searching we found the following leads. I don't know whether they are good or bad: Mirroring all the discs to a second set of drives. So we would have the possibility to try different things without loosing more than we already have. Trying to rebuild the array in R-Studio. But we have no real experience with the software. Pulling all drives, rebooting the system, changing into the areca controller bios, reinserting the HDDs one-by-one. Some people are saying that the brought the system online by this. Some are saying that the effect is zero. Some say, that they blew the whole thing. Using undocumented areca commands like "rescue" or "LeVel2ReScUe". Contacting a computer forensics service. But whoa... primary estimates by phone exceeded 20.000€. That's why we would kindly ask for help. Maybe we are missing the obvious? And yes of course, we have backups. But some systems lost one week of data, thats why we'd like to get the system up and running again. Any help, suggestions and questions are more than welcome.

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  • Man pages not finding entry

    - by Mike
    So, I'm not sure what is going on with my system (ubuntu 12.04), but my man pages do not seem to be working. I try man gcc and get the following response No manual entry for gcc See 'man 7 undocumented' for help when manual pages are not available. However I see the man entry in /usr/share/man/man1/gcc.1.gz Here is what my /etc/manpath.config file looks like # manpath.config # # This file is used by the man-db package to configure the man and cat paths. # It is also used to provide a manpath for those without one by examining # their PATH environment variable. For details see the manpath(5) man page. # # Lines beginning with `#' are comments and are ignored. Any combination of # tabs or spaces may be used as `whitespace' separators. # # There are three mappings allowed in this file: # -------------------------------------------------------- # MANDATORY_MANPATH manpath_element # MANPATH_MAP path_element manpath_element # MANDB_MAP global_manpath [relative_catpath] #--------------------------------------------------------- # every automatically generated MANPATH includes these fields # #MANDATORY_MANPATH /usr/src/pvm3/man # MANDATORY_MANPATH /usr/man MANDATORY_MANPATH /usr/share/man MANDATORY_MANPATH /usr/local/share/man #--------------------------------------------------------- # set up PATH to MANPATH mapping # ie. what man tree holds man pages for what binary directory. # # *PATH* -> *MANPATH* # MANPATH_MAP /bin /usr/share/man MANPATH_MAP /usr/bin /usr/share/man MANPATH_MAP /sbin /usr/share/man MANPATH_MAP /usr/sbin /usr/share/man MANPATH_MAP /usr/local/bin /usr/local/man MANPATH_MAP /usr/local/bin /usr/local/share/man MANPATH_MAP /usr/local/sbin /usr/local/man MANPATH_MAP /usr/local/sbin /usr/local/share/man MANPATH_MAP /usr/X11R6/bin /usr/X11R6/man MANPATH_MAP /usr/bin/X11 /usr/X11R6/man MANPATH_MAP /usr/games /usr/share/man MANPATH_MAP /opt/bin /opt/man MANPATH_MAP /opt/sbin /opt/man #--------------------------------------------------------- # For a manpath element to be treated as a system manpath (as most of those # above should normally be), it must be mentioned below. Each line may have # an optional extra string indicating the catpath associated with the # manpath. If no catpath string is used, the catpath will default to the # given manpath. # # You *must* provide all system manpaths, including manpaths for alternate # operating systems, locale specific manpaths, and combinations of both, if # they exist, otherwise the permissions of the user running man/mandb will # be used to manipulate the manual pages. Also, mandb will not initialise # the database cache for any manpaths not mentioned below unless explicitly # requested to do so. # # In a per-user configuration file, this directive only controls the # location of catpaths and the creation of database caches; it has no effect # on privileges. # # Any manpaths that are subdirectories of other manpaths must be mentioned # *before* the containing manpath. E.g. /usr/man/preformat must be listed # before /usr/man. # # *MANPATH* -> *CATPATH* # MANDB_MAP /usr/man /var/cache/man/fsstnd MANDB_MAP /usr/share/man /var/cache/man MANDB_MAP /usr/local/man /var/cache/man/oldlocal MANDB_MAP /usr/local/share/man /var/cache/man/local MANDB_MAP /usr/X11R6/man /var/cache/man/X11R6 MANDB_MAP /opt/man /var/cache/man/opt # #--------------------------------------------------------- # Program definitions. These are commented out by default as the value # of the definition is already the default. To change: uncomment a # definition and modify it. # #DEFINE pager pager -s #DEFINE cat cat #DEFINE tr tr '\255\267\264\327' '\055\157\047\170' #DEFINE grep grep #DEFINE troff groff -mandoc #DEFINE nroff nroff -mandoc #DEFINE eqn eqn #DEFINE neqn neqn #DEFINE tbl tbl #DEFINE col col #DEFINE vgrind vgrind #DEFINE refer refer #DEFINE grap grap #DEFINE pic pic -S # #DEFINE compressor gzip -c7 #--------------------------------------------------------- # Misc definitions: same as program definitions above. # #DEFINE whatis_grep_flags -i #DEFINE apropos_grep_flags -iEw #DEFINE apropos_regex_grep_flags -iE #--------------------------------------------------------- # Section names. Manual sections will be searched in the order listed here; # the default is 1, n, l, 8, 3, 0, 2, 5, 4, 9, 6, 7. Multiple SECTION # directives may be given for clarity, and will be concatenated together in # the expected way. # If a particular extension is not in this list (say, 1mh), it will be # displayed with the rest of the section it belongs to. The effect of this # is that you only need to explicitly list extensions if you want to force a # particular order. Sections with extensions should usually be adjacent to # their main section (e.g. "1 1mh 8 ..."). # SECTION 1 n l 8 3 2 3posix 3pm 3perl 5 4 9 6 7 # #--------------------------------------------------------- # Range of terminal widths permitted when displaying cat pages. If the # terminal falls outside this range, cat pages will not be created (if # missing) or displayed. # #MINCATWIDTH 80 #MAXCATWIDTH 80 # # If CATWIDTH is set to a non-zero number, cat pages will always be # formatted for a terminal of the given width, regardless of the width of # the terminal actually being used. This should generally be within the # range set by MINCATWIDTH and MAXCATWIDTH. # #CATWIDTH 0 # #--------------------------------------------------------- # Flags. # NOCACHE keeps man from creating cat pages. #NOCACHE Thanks for any help (p.s. even 'man man' fails) Edit: When I run ls -l /usr/share/man/man1/gcc* I get the following output lrwxrwxrwx 1 root root 12 May 27 15:41 /usr/share/man/man1/gcc.1.gz -> gcc-4.6.1.gz -rw-r--r-- 1 root root 217776 Apr 15 17:34 /usr/share/man/man1/gcc-4.6.1.gz

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  • Azure Mobile Services: available modules

    - by svdoever
    Azure Mobile Services has documented a set of objects available in your Azure Mobile Services server side scripts at their documentation page Mobile Services server script reference. Although the documented list is a nice list of objects for the common things you want to do, it will be sooner than later that you will look for more functionality to be included in your script, especially with the new provided feature that you can now create your custom API’s. If you use GIT it is now possible to add any NPM module (node package manager module, say the NuGet of the node world), but why include a module if it is already available out of the box. And you can only use GIT with Azure Mobile Services if you are an administrator on your Azure Mobile Service, not if you are a co-administrator (will be solved in the future). Until now I did some trial and error experimentation to test if a certain module was available. This is easiest to do as follows:   Create a custom API, for example named experiment. In this API use the following code: exports.get = function (request, response) { var module = "nonexistingmodule"; var m = require(module); response.send(200, "Module '%s' found.", module); }; You can now test your service with the following request in your browser: https://yourservice.azure-mobile.net/api/experiment If you get the result: {"code":500,"error":"Error: Internal Server Error"} you know that the module does not exist. In your logs you will find the following error: Error in script '/api/experiment.json'. Error: Cannot find module 'nonexistingmodule' [external code] atC:\DWASFiles\Sites\yourservice\VirtualDirectory0\site\wwwroot\App_Data\config\scripts\api\experiment.js:3:13[external code] If you require an existing (undocumented) module like the OAuth module in the following code, you will get success as a result: exports.get = function (request, response) { var module = "oauth"; var m = require(module); response.send(200, "Module '" + module + "' found."); }; If we look at the standard node.js documentation we see an extensive list of modules that can be used from your code. If we look at the list of files available in the Azure Mobile Services platform as documented in the blog post Azure Mobile Services: what files does it consist of? we see a folder node_modules with many more modules are used to build the Azure Mobile Services functionality on, but that can also be utilized from your server side node script code: apn - An interface to the Apple Push Notification service for Node.js. dpush - Send push notifications to Android devices using GCM. mpns - A Node.js interface to the Microsoft Push Notification Service (MPNS) for Windows Phone. wns - Send push notifications to Windows 8 devices using WNS. pusher - Node library for the Pusher server API (see also: http://pusher.com/) azure - Windows Azure Client Library for node. express - Sinatra inspired web development framework. oauth - Library for interacting with OAuth 1.0, 1.0A, 2 and Echo. Provides simplified client access and allows for construction of more complex apis and OAuth providers. request - Simplified HTTP request client. sax - An evented streaming XML parser in JavaScript sendgrid - A NodeJS implementation of the SendGrid Api. sqlserver – In node repository known as msnodesql - Microsoft Driver for Node.js for SQL Server. tripwire - Break out from scripts blocking node.js event loop. underscore - JavaScript's functional programming helper library. underscore.string - String manipulation extensions for Underscore.js javascript library. xml2js - Simple XML to JavaScript object converter. xmlbuilder - An XML builder for node.js. As stated before, many of these modules are used to provide the functionality of Azure Mobile Services platform, and in general should not be used directly. On the other hand, I needed OAuth badly to authenticate to the new v1.1 services of Twitter, and was very happy that a require('oauth') and a few lines of code did the job. Based on the above modules and a lot of code in the other javascript files in the Azure Mobile Services platform a set of global objects is provided that can be used from your server side node.js script code. In future blog posts I will go into more details with respect to how this code is built-up, all starting at the node.js express entry point app.js.

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  • Five development tools I can't live without

    - by bconlon
    When applying to join Geeks with Blogs I had to specify the development tools I use every day. That got me thinking, it's taken a long time to whittle my tools of choice down to the selection I use, so it might be worth sharing. Before I begin, I appreciate we all have our preferred development tools, but these are the ones that work for me. Microsoft Visual Studio Microsoft Visual Studio has been my development tool of choice for more years than I care to remember. I first used this when it was Visual C++ 1.5 (hats off to those who started on 1.0) and by 2.2 it had everything I needed from a C++ IDE. Versions 4 and 5 followed and if I had to guess I would expect more Windows applications are written in VC++ 6 and VB6 than any other language. Then came the not so great versions Visual Studio .Net 2002 (7.0) and 2003 (7.1). If I'm honest I was still using v6. 2005 was better and 2008 was simply brilliant. Everything worked, the compiler was super fast and I was happy again...then came 2010...oh dear. 2010 is a big step backwards for me. It's not encouraging for my upcoming WPF exploits that 2010 is fronted in WPF technology, with the forever growing Find/Replace dialog, the issues with C++ intellisense, and the buggy debugger. That said it is still my tool of choice but I hope they sort the issue in SP1. I've tried other IDEs like Visual Age and Eclipse, but for me Visual Studio is the best. A really great tool. Liquid XML Studio XML development is a tricky business. The W3C standards are often difficult to get to the bottom of so it's great to have a graphical tool to help. I first used Liquid Technologies 5 or 6 years back when I needed to process XML data in C++. Their excellent XML Data Binding tool has an easy to use Wizard UI (as compared to Castor or JAXB command line tools) and allows you to generate code from an XML Schema. So instead of having to deal with untyped nodes like with a DOM parser, instead you get an Object Model providing a custom API in C++, C#, VB etc. More recently they developed a graphical XML IDE with XML Editor, XSLT, XQuery debugger and other XML tools. So now I can develop an XML Schema graphically, click a button to generate a Sample XML document, and click another button to run the Wizard to generate code including a Sample Application that will then load my Sample XML document into the generated object model. This is a very cool toolset. Note: XML Data Binding is nothing to do with WPF Data Binding, but I hope to cover both in more detail another time. .Net Reflector Note: I've just noticed that starting form the end of February 2011 this will no longer be a free tool !! .Net Reflector turns .Net byte code back into C# source code. But how can it work this magic? Well the clue is in the name, it uses reflection to inspect a compiled .Net assembly. The assembly is compiled to byte code, it doesn't get compiled to native machine code until its needed using a just-in-time (JIT) compiler. The byte code still has all of the information needed to see classes, variables. methods and properties, so reflector gathers this information and puts it in a handy tree. I have used .Net Reflector for years in order to understand what the .Net Framework is doing as it sometimes has undocumented, quirky features. This really has been invaluable in certain instances and I cannot praise enough kudos on the original developer Lutz Roeder. Smart Assembly In order to stop nosy geeks looking at our code using a tool like .Net Reflector, we need to obfuscate (mess up) the byte code. Smart Assembly is a tool that does this. Again I have used this for a long time. It is very quick and easy to use. Another excellent tool. Coincidentally, .Net Reflector and Smart Assembly are now both owned by Red Gate. Again kudos goes to the original developer Jean-Sebastien Lange. TortoiseSVN SVN (Apache Subversion) is a Source Control System developed as an open source project. TortoiseSVN is a graphical UI wrapper over SVN that hooks into Windows Explorer to enable files to be Updated, Committed, Merged etc. from the right click menu. This is an essential tool for keeping my hard work safe! Many years ago I used Microsoft Source Safe and I disliked CVS type systems. But TortoiseSVN is simply the best source control tool I have ever used. --- So there you have it, my top 5 development tools that I use (nearly) every day and have helped to make my working life a little easier. I'm sure there are other great tools that I wish I used but have never heard of, but if you have not used any of the above, I would suggest you check them out as they are all very, very cool products. #

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  • Solaris 11.2: Functional Deprecation

    - by alanc
    In Solaris 11.1, I updated the system headers to enable use of several attributes on functions, including noreturn and printf format, to give compilers and static analyzers more information about how they are used to give better warnings when building code. In Solaris 11.2, I've gone back in and added one more attribute to a number of functions in the system headers: __attribute__((__deprecated__)). This is used to warn people building software that they’re using function calls we recommend no longer be used. While in many cases the Solaris Binary Compatibility Guarantee means we won't ever remove these functions from the system libraries, we still want to discourage their use. I made passes through both the POSIX and C standards, and some of the Solaris architecture review cases to come up with an initial list which the Solaris architecture review committee accepted to start with. This set is by no means a complete list of Obsolete function interfaces, but should be a reasonable start at functions that are well documented as deprecated and seem useful to warn developers away from. More functions may be flagged in the future as they get deprecated, or if further passes are made through our existing deprecated functions to flag more of them. Header Interface Deprecated by Alternative Documented in <door.h> door_cred(3C) PSARC/2002/188 door_ucred(3C) door_cred(3C) <kvm.h> kvm_read(3KVM), kvm_write(3KVM) PSARC/1995/186 Functions on kvm_kread(3KVM) man page kvm_read(3KVM) <stdio.h> gets(3C) ISO C99 TC3 (Removed in ISO C11), POSIX:2008/XPG7/Unix08 fgets(3C) gets(3C) man page, and just about every gets(3C) reference online from the past 25 years, since the Morris worm proved bad things happen when it’s used. <unistd.h> vfork(2) PSARC/2004/760, POSIX:2001/XPG6/Unix03 (Removed in POSIX:2008/XPG7/Unix08) posix_spawn(3C) vfork(2) man page. <utmp.h> All functions from getutent(3C) man page PSARC/1999/103 utmpx functions from getutentx(3C) man page getutent(3C) man page <varargs.h> varargs.h version of va_list typedef ANSI/ISO C89 standard <stdarg.h> varargs(3EXT) <volmgt.h> All functions PSARC/2005/672 hal(5) API volmgt_check(3VOLMGT), etc. <sys/nvpair.h> nvlist_add_boolean(3NVPAIR), nvlist_lookup_boolean(3NVPAIR) PSARC/2003/587 nvlist_add_boolean_value, nvlist_lookup_boolean_value nvlist_add_boolean(3NVPAIR) & (9F), nvlist_lookup_boolean(3NVPAIR) & (9F). <sys/processor.h> gethomelgroup(3C) PSARC/2003/034 lgrp_home(3LGRP) gethomelgroup(3C) <sys/stat_impl.h> _fxstat, _xstat, _lxstat, _xmknod PSARC/2009/657 stat(2) old functions are undocumented remains of SVR3/COFF compatibility support If the above table is cut off when viewing in the blog, try viewing this standalone copy of the table. To See or Not To See To see these warnings, you will need to be building with either gcc (versions 3.4, 4.5, 4.7, & 4.8 are available in the 11.2 package repo), or with Oracle Solaris Studio 12.4 or later (which like Solaris 11.2, is currently in beta testing). For instance, take this oversimplified (and obviously buggy) implementation of the cat command: #include <stdio.h> int main(int argc, char **argv) { char buf[80]; while (gets(buf) != NULL) puts(buf); return 0; } Compiling it with the Studio 12.4 beta compiler will produce warnings such as: % cc -V cc: Sun C 5.13 SunOS_i386 Beta 2014/03/11 % cc gets_test.c "gets_test.c", line 6: warning: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 The exact warning given varies by compilers, and the compilers also have a variety of flags to either raise the warnings to errors, or silence them. Of couse, the exact form of the output is Not An Interface that can be relied on for automated parsing, just shown for example. gets(3C) is actually a special case — as noted above, it is no longer part of the C Standard Library in the C11 standard, so when compiling in C11 mode (i.e. when __STDC_VERSION__ >= 201112L), the <stdio.h> header will not provide a prototype for it, causing the compiler to complain it is unknown: % gcc -std=c11 gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: implicit declaration of function ‘gets’ [-Wimplicit-function-declaration] while (gets(buf) != NULL) ^ The gets(3C) function of course is still in libc, so if you ignore the error or provide your own prototype, you can still build code that calls it, you just have to acknowledge you’re taking on the risk of doing so yourself. Solaris Studio 12.4 Beta % cc gets_test.c "gets_test.c", line 6: warning: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 % cc -errwarn=E_DEPRECATED_ATT gets_test.c "gets_test.c", line 6: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 cc: acomp failed for gets_test.c This warning is silenced in the 12.4 beta by cc -erroff=E_DEPRECATED_ATT No warning is currently issued by Studio 12.3 & earler releases. gcc 3.4.3 % /usr/sfw/bin/gcc gets_test.c gets_test.c: In function `main': gets_test.c:6: warning: `gets' is deprecated (declared at /usr/include/iso/stdio_iso.h:221) Warning is completely silenced with gcc -Wno-deprecated-declarations gcc 4.7.3 % /usr/gcc/4.7/bin/gcc gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Wdeprecated-declarations] % /usr/gcc/4.7/bin/gcc -Werror=deprecated-declarations gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: error: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Werror=deprecated-declarations] cc1: some warnings being treated as errors Warning is completely silenced with gcc -Wno-deprecated-declarations gcc 4.8.2 % /usr/bin/gcc gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Wdeprecated-declarations] while (gets(buf) != NULL) ^ % /usr/bin/gcc -Werror=deprecated-declarations gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: error: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Werror=deprecated-declarations] while (gets(buf) != NULL) ^ cc1: some warnings being treated as errors Warning is completely silenced with gcc -Wno-deprecated-declarations

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  • How does mysql define DISTINCT() in reference documentation

    - by goran
    EDIT: This question is about finding definitive reference to MySQL syntax on SELECT modifying keywords and functions. /EDIT AFAIK SQL defines two uses of DISTINCT keywords - SELECT DISTINCT field... and SELECT COUNT(DISTINCT field) ... However in one of web applications that I administer I've noticed performance issues on queries like SELECT DISTINCT(field1), field2, field3 ... DISTINCT() on a single column makes no sense and I am almost sure it is interpreted as SELECT DISTINCT field1, field2, field3 ... but how can I prove this? I've searched mysql site for a reference on this particular syntax, but could not find any. Does anyone have a link to definition of DISTINCT() in mysql or knows about other authoritative source on this? Best EDIT After asking the same question on mysql forums I learned that while parsing the SQL mysql does not care about whitespace between functions and column names (but I am still missing a reference). As it seems you can have whitespace between functions and the parenthesis SELECT LEFT (field1,1), field2... and get mysql to understand it as SELECT LEFT(field,1) Similarly SELECT DISTINCT(field1), field2... seems to get decomposed to SELECT DISTINCT (field1), field2... and then DISTINCT is taken not as some undefined (or undocumented) function, but as SELECT modifying keyword and the parenthesis around field1 are evaluated as if they were part of field expression. It would be great if someone would have a pointer to documentation where it is stated that the whitespace between functions and parenthesis is not significant or to provide links to apropriate MySQL forums, mailing lists where I could raise a question to put this into reference. EDIT I have found a reference to server option IGNORE SPACE. It states that "The IGNORE SPACE SQL mode can be used to modify how the parser treats function names that are whitespace-sensitive", later on it states that recent versions of mysql have reduced this number from 200 to 30. One of the remaining 30 is COUNT for example. With IGNORE SPACE enabled both SELECT COUNT(*) FROM mytable; SELECT COUNT (*) FROM mytable; are legal. So if this is an exception, I am left to conclude that normally functions ignore space by default. If functions ignore space by default then if the context is ambiguous, such as for the first function on a first item of the select expression, then they are not distinguishable from keywords and the error can not be thrown and MySQL must accept them as keywords. Still, my conclusions feel like they have lot of assumptions, I would still be grateful and accept any pointers to see where to follow up on this.

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  • Playing dynamically embedded sound object via Javascript

    - by Vikram Goyal
    I need to background load some WAV files for an HTML page using AJAX. I use AJAX to get the details of the WAV files, then use the embed tag, and I can confirm that the files have loaded successfully because when I set autostart to true, the files play. However, I need the files to play only when the user clicks on a button (or an event is fired). The following is my code to preload these files: function preloadMedia() { for(var i = 0; i < testQuestions.length; i++) { var soundEmbed = document.createElement("embed"); soundEmbed.setAttribute("src", "/media/sounds/" + testQuestions[i].mediaFile); soundEmbed.setAttribute("hidden", true); soundEmbed.setAttribute("id", testQuestions[i].id); soundEmbed.setAttribute("autostart", false); soundEmbed.setAttribute("width", 0); soundEmbed.setAttribute("height", 0); soundEmbed.setAttribute("enablejavascript", true); document.body.appendChild((soundEmbed)); } } I use the following code to play the file (based on what sound file that user wants to play) function soundPlay(which) { var sounder = document.getElementById(which); sounder.Play(); } Something is wrong here, as none of the browsers I have tested on play the files using the code above. There are no errors, and the code just returns. I would have left it at that (that is - I would have convinced the client to convert all WAV's to MP3 and use MooTools). But I realized that I could play the sound files, which were not dynamically embeded. Thus, the same soundPlay function would work for a file embeded in the following manner: <embed src="/media/sounds/hug_sw1.wav" id="sound2" width="0" heigh="0" autostart="false" enablejavascript="true"/> anywhere within the HTML. And it plays well in all the browsers. Anyone have a clue on this? Is this some sort of undocumented security restriction in all the browsers? (Please remember that the files do get preloaded dynamically, as I can confirm by setting the autostart property to true - They all play). Any help appreciated.

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  • Rails ActiveResource Associations

    - by brad
    I have some ARes models (see below) that I'm trying to use associations with (which seems to be wholly undocumented and maybe not possible but I thought I'd give it a try) So on my service side, my ActiveRecord object will render something like render :xml => @group.to_xml(:include => :customers) (see generated xml below) The models Group and Customers are HABTM On my ARes side, I'm hoping that it can see the <customers> xml attribute and automatically populate the .customers attribute of that Group object , but the has_many etc methods aren't supported (at least as far as I can tell) So I'm wondering how ARes does it's reflection on the XML to set the attributes of an object. In AR for instance I could create a def customers=(customer_array) and set it myself, but this doesn't seem to work in ARes. One suggestion I found for an "association" is the just have a method def customers Customer.find(:all, :conditions => {:group_id => self.id}) end But this has the disadvantage that it makes a second service call to look up those customers... not cool I'd like my ActiveResource model to see that the customers attribute in the XML and automatically populate my model. Anyone have any experience with this?? # My Services class Customer < ActiveRecord::Base has_and_belongs_to_many :groups end class Group < ActiveRecord::Base has_and_belongs_to_many :customer end # My ActiveResource accessors class Customer < ActiveResource::Base; end class Group < ActiveResource::Base; end # XML from /groups/:id?customers=true <group> <domain>some.domain.com</domain> <id type="integer">266</id> <name>Some Name</name> <customers type="array"> <customer> <active type="boolean">true</active> <id type="integer">1</id> <name>Some Name</name> </customer> <customer> <active type="boolean" nil="true"></active> <id type="integer">306</id> <name>Some Other Name</name> </customer> </customers> </group>

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  • How do I access SourceGear Web services using SOAP::Lite?

    - by user565793
    For some reason SourceGear provide an undocumented Web service on their installations. They actually ask developers to use the API instead because the Web service is kinda messy, but this is a problem in my case because I cannot use this API on a Perl environment, so their solution for my specific case is to use the Web service. This shouldn't be a problem. Using SOAP::Lite I have connected to several Web services in the past in the same way. But the lack of documentation is a major chaos if you don't know where the SOAP calls can be made. I only have an XML to decipher where to and how to make these calls. It would be great if a real SOAP genius could help me out in this. This is an example of the login call and the expected response: Request POST /fortress/dragnetwebservice.asmx HTTP/1.1 Host: velecloudserver Content-Type: text/xml; charset=utf-8 Content-Length: length SOAPAction: "http://www.sourcegear.com/schemas/dragnet/LoginPlainText" <?xml version="1.0" encoding="utf-8"?> <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> <soap:Body> <LoginPlainText xmlns="http://www.sourcegear.com/schemas/dragnet"> <strLogin>string</strLogin> <strPassword>string</strPassword> </LoginPlainText> </soap:Body> </soap:Envelope> Response HTTP/1.1 200 OK Content-Type: text/xml; charset=utf-8 Content-Length: length <?xml version="1.0" encoding="utf-8"?> <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> <soap:Body> <LoginPlainTextResponse xmlns="http://www.sourcegear.com/schemas/dragnet"> <LoginPlainTextResult>int</LoginPlainTextResult> <strAuthTicket>string</strAuthTicket> </LoginPlainTextResponse> </soap:Body> </soap:Envelope> I'm looking for a way to be able to assemble this somehow. This is my Perl example: my $soap = SOAP::Lite -> uri ('http://velecloudserver/fortress/dragnetwebservice.asmx') -> proxy('http://velecloudserver/fortress/dragnetwebservice.asmx/LoginPlainText'); my $som = $soap->call('LoginPlainText', SOAP::Data->name('LoginPlainText')->value( \SOAP::Data->value([ SOAP::Data->name('strLogin')->value( 'admin' ), SOAP::Data->name('strPassword')->value('Adm1234'), ])) ); Any tip would be appreciated.

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  • XmlHttpRequest bug?

    - by valdo
    Hello all. I'm writing a program that among other things needs to download a file given its URL. I'm too lazy to implement the Http/Https protocols manually, so that I needed some library/object/function that'll do the job. Critical requirement: The download must be asynchronous. That is, the thread that issued the download must be able to do something else "while" downloading the file, plus the download must be able to be aborted anytime without any barbaric side effects (such as internal call to TerminateThread). Nice-to-have requirements: Should be able to download the file "into memory". Means - read the contents of the file as they arrive, not necessarily save it into some "file system" file. It'd be nice to have some convenient Win32 progress notification mechanism (waitable event, semahpore, completion port, etc.), rather than just periodically polling the download status. I've chosen the XmlHttpRequest COM object to do the work. It seemed to work fine enough, plus it supported asynchronous mode. However I noticed that after some period it just stops working. That is, after several successful file downloads it stops downloading anything. I periodically poll it to get its status, it reports "in-progress", but nothing actually happens, and there's no network activity. Moreover, when the same process creates another instance of XmlHttpRequest object to perform new downloads - the effect is the same. The object reports "in progress", whereas it doesn't even try to connect to the server (according to network sniffers and system TCP state). The only way to make this object work back is to restart the process. This makes me suspect that there's a sort of a bug (sorry, I meant undocumented feature) in the object. Also it's not a bug at the level of an individual object, since the problem persists when the object is destroyed and another one is created. It's probably some global state of the DLL that implements this object. Does anyone know something about this? Is this a known bug? I'm pretty sure there's no chance that I have another bug in my code, because of which it seems to me to be the bug is in the XmlHttpRequest. I've done enoughtests and spent time with the debugger to conclude without reasonable doubt that it's just the object stops working. BTW, while the object should work, I do all the waiting via MsgWaitXXXX API calls. So that if this object needs the message loop to work properly (for instance, it may create a hidden notification window and bind it to a socket via WSAAsyncSelect) - I give it the opportunity.

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  • how to deal with the position in a c# stream

    - by CapsicumDreams
    The (entire) documentation for the position property on a stream says: When overridden in a derived class, gets or sets the position within the current stream. The Position property does not keep track of the number of bytes from the stream that have been consumed, skipped, or both. That's it. OK, so we're fairly clear on what it doesn't tell us, but I'd really like to know what it in fact does stand for. What is 'the position' for? Why would we want to alter or read it? If we change it - what happens? In a pratical example, I have a a stream that periodically gets written to, and I have a thread that attempts to read from it (ideally ASAP). From reading many SO issues, I reset the position field to zero to start my reading. Once this is done: Does this affect where the writer to this stream is going to attempt to put the data? Do I need to keep track of the last write position myself? (ie if I set the position to zero to read, does the writer begin to overwrite everything from the first byte?) If so, do I need a semaphore/lock around this 'position' field (subclassing, perhaps?) due to my two threads accessing it? If I don't handle this property, does the writer just overflow the buffer? Perhaps I don't understand the Stream itself - I'm regarding it as a FIFO pipe: shove data in at one end, and suck it out at the other. If it's not like this, then do I have to keep copying the data past my last read (ie from position 0x84 on) back to the start of my buffer? I've seriously tried to research all of this for quite some time - but I'm new to .NET. Perhaps the Streams have a long, proud (undocumented) history that everyone else implicitly understands. But for a newcomer, it's like reading the manual to your car, and finding out: The accelerator pedal affects the volume of fuel and air sent to the fuel injectors. It does not affect the volume of the entertainment system, or the air pressure in any of the tires, if fitted. Technically true, but seriously, what we want to know is that if we mash it to the floor you go faster..

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  • What is the proper way to change the UINavigationController transition effect

    - by Felipe Sabino
    I have seen lots of people asking on how to push/pop UINavigationControllers using other animations besides the default one, like flip or curl. The problem is that either the question/answer was relative old, which means the have some things like [UIView beginAnimations:] (example here) or they use two very different approaches. The first is to use UIView's transitionFromView:toView:duration:options:completion: selector before pushing the controller (with the animation flag set to NO), like the following: UIViewController *ctrl = [[UIViewController alloc] init]; [UIView transitionFromView:self.view toView:ctrl.view duration:1 options:UIViewAnimationOptionTransitionFlipFromTop completion:nil]; [self.navigationController pushViewController:ctrl animated:NO]; Another one is to use CoreAnimation explicitly with a CATransaction like the following: // remember you will have to have the QuartzCore framework added to your project for this approach and also add <QuartzCore/QuartzCore.h> to the class this code is used CATransition* transition = [CATransition animation]; transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]; transition.duration = 1.0f; transition.type = @"flip"; transition.subtype = @"fromTop"; [self.navigationController.view.layer removeAllAnimations]; [self.navigationController.view.layer addAnimation:transition forKey:kCATransition]; UIViewController *ctrl = [[UIViewController alloc] init]; [self.navigationController pushViewController:ctrl animated:NO]; There are pros and cons for both approaches. The first approach gives me a much cleaner code but restricts me from using animations like "suckEffect", "cube" and others. The second approach feels wrong just by looking at it. It starts by using undocumented transitions types (i.e. not present in the Common transition types documentation from CATransition Class Reference) which might get your app rejected from App Store (I mean might as I could not found any reference of apps being rejected because it was using this transactions, which I would also appreciate any clarification on this matter), but it gives you much more flexibility on your animations, as I can use other animation types such as "cameraIris", "rippleEffect" and so on. Regarding all that, do I really need to appeal for QuartzCore and CoreAnimation whenever I need a fancier UINavigationController transition? Is there any other way to accomplish the same effect using only UIKit? If not, will the use of string values like "flip" and "cube" instead of the pre-defined constants (kCATransitionFade, kCATransitionMoveIn, etc...) be an issue regarding my app approval in the App Store? Also, are there other pros and cons regarding both approaches that could help me deciding whether to choose each one of them?

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  • Huawei b153 limit of devices

    - by bdecaf
    I set up my home network all through this 3G wifi router. Problem is it only allows 5 devices to connect. That's not much especially if a wifi printer and gaming consoles keep hogging these slots. On the other hand I don't see the point on blocking these devices. They are (should) not doing anything online just intern in my network. The documentation I can find is surpirisingly unhelpful and focuses how to plug the device in a power socket. So what would be my options. Notes: I have already been able to get a shell on the device using ssh. It's running some Busybox. But I fail to find the how and where this limit is enforced/created. Notes 2: Specifically my device is a 3WebCube - unfortunately not specifically marked with the Huawei Model number. Successes so far After enabling ssh in the options I can login: ssh -T [email protected] [email protected]'s password: ------------------------------- -----Welcome to ATP Cli------ ------------------------------- unfortunately because of this -T - the tab key does not work for autocomplete and all inputted commands will be echoed. Also no history with arrow keys. ATP interface this custom interface is not very useful: ATP>help help Welcome to ATP command line tool. If any question, please input "?" at the end of command. ATP>? ? cls debug help save ? exit ATP>save? save? Command failed. ATP>save ? save ? ATP>debug ? debug ? display set trace ? Shell BUT undocumented - I somehow found on a auto translated chinese website - all you need to do is input sh ATP>sh sh BusyBox vv1.9.1 (2011-03-27 11:59:11 CST) built-in shell (ash) Enter 'help' for a list of built-in commands. # builtin commands # help Built-in commands: ------------------- . : alias bg break cd chdir command continue eval exec exit export false fg getopts hash help jobs kill let local pwd read readonly return set shift source times trap true type ulimit umask unalias unset wait shows standard unix structure: # ls / var tmp proc linuxrc init etc bin usr sbin mnt lib html dev in /bin # ls /bin zebra strace ppps ln echo cat wscd startbsp pppc klog ebtables busybox wlancmd sshd ping kill dns brctl web sntp netstat iwpriv dhcps auth usbdiagd sms mount iwcontrol dhcpc atserver upnp sleep mknod iptables date atcmd upg siproxd mkdir ipcheck cp at umount sh mini_upnpd ip console ash test_at rm mic igmpproxy cms telnetd ripd ls ethcmd cmgr swapdev ps log equipcmd cli in /sbin # ls /sbin vconfig reboot insmod ifconfig arp route poweroff init halt using tftp after installing tftp on my desktop I was able to send files with tftp -s -l curcfg.xml 192.168.1.103 and to download onto the huawei with tftp -g -r curcfg.xml 192.168.1.103 I think I'll need that - because I don't see any editor installed. readout stuff (still playing around where I would get interesting info) For confirmation of hardware: # cat /var/log/modem_hardware_name ^HWVER:"WL1B153M001"# # cat /var/log/modem_software_name 1096.11.03.02.107 # cat /var/log/product_name B153

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  • Process not Listed by PS or in /proc/

    - by Hammer Bro.
    I'm trying to figure out how to operate a rather large Java program, 'prog'. If I go to its /bin/ dir and configure its setenv.sh and prog.sh to use local directories and my current user account. Then I try to run it via "./prog.sh start". Here are all the relevant bits of prog.sh: USER=(my current account) _CMD="/opt/jdk/bin/java -server -Xmx768m -classpath "${CLASSPATH}" -jar "${DIR}/prog.jar"" case "${ACTION}" in start) nohup su ${USER} -c "exec ${_CMD} >>${_LOGFILE} 2>&1" >/dev/null & echo $! >${_PID} echo "Prog running. PID="`cat ${_PID}` ;; stop) PID=`cat ${_PID} 2>/dev/null` echo "Shutting down prog: ${PID} kill -QUIT ${PID} 2>/dev/null kill ${PID} 2>/dev/null kill -KILL ${PID} 2>/dev/null rm -f ${_PID} echo "STOPPED `date`" >>${_LOGFILE} ;; When I actually do ./prog.sh start, it starts. But I can't find it at all on the process list. Nor can I kill it manually, using the same command the shell script uses. But I can tell it's running, because if I do ./prog.sh stop, it stops (and some temporary files elsewhere clean themselves out). ./prog.sh start Prog running. PID=1234 ps eaux | grep 1234 ps eaux | grep -i prog.jar ps eaux >> pslist.txt (It's not there either by PID or any clear name I can find: prog, java or jar.) cd /proc/1234/ -bash: cd: /proc/1234/: No such file or directory kill -QUIT 1234 kill 1234 kill -KILL 1234 -bash: kill: (1234) - No such process ./prog.sh stop Shutting down prog: 1234 As far as I can tell, the process is running yet not in any way listed by the system. I can't find it in ps or /proc/, nor can I kill it. But the shell script can still stop it properly. So my question is, how can something like this happen? Is the process supremely hidden, actually unlisted, or am I just missing it in some fashion? I'm trying to figure out what makes this program tick, and I can barely prove that it's ticking! Edit: ps eu | grep prog.sh (after having restarted; so random PID) 50038 19381 0.0 0.0 4412 632 pts/3 S+ 16:09 0:00 grep prog.sh HOSTNAME=machine.server.com TERM=vt100 SHELL=/bin/bash HISTSIZE=1000 SSH_CLIENT=::[STUFF] 1754 22 CVSROOT=:[DIR] SSH_TTY=/dev/pts/3 ANT_HOME=/opt/apache-ant-1.7.1 USER=[USER] LS_COLORS=[COLORS] SSH_AUTH_SOCK=[DIR] KDEDIR=/usr MAIL=[DIR] PATH=[DIRS] INPUTRC=/etc/inputrc PWD=[PWD] JAVA_HOME=/opt/jdk1.6.0_21 LANG=en_US.UTF-8 SSH_ASKPASS=/usr/libexec/openssh/gnome-ssh-askpass M2_HOME=/opt/apache-maven-2.2.1 SHLVL=1 HOME=[~] LOGNAME=[USER] SSH_CONNECTION=::[STUFF] LESSOPEN=|/usr/bin/lesspipe.sh %s G_BROKEN_FILENAMES=1 _=/bin/grep OLDPWD=[DIR] I just realized that the stop) part of prog.sh isn't actually a guarantee that the process it claims to be stopping is running -- it just tries to kill the PID and suppresses all output then deletes the temporary file and manually inserts STOPPED into the log file. So I'm no longer so certain that the process is always running when I ps for it, although the code sample above indicates that it at least runs erratically. I'll continue looking into this undocumented behemoth when I return to work tomorrow.

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  • CodePlex Daily Summary for Sunday, May 09, 2010

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

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  • Merge replication stopping without errors in SQL 2008 R2

    - by Rob Farley
    A non-SQL MVP friend of mine, who also happens to be a client, asked me for some help again last week. I was planning on writing this up even before Rob Volk (@sql_r) listed his T-SQL Tuesday topic for this month. Earlier in the year, I (well, LobsterPot Solutions, although I’d been the person mostly involved) had helped out with a merge replication problem. The Merge Agent on the subscriber was just stopping every time, shortly after it started. With no errors anywhere – not in the Windows Event Log, the SQL Agent logs, not anywhere. We’d managed to get the system working again, but didn’t have a good reason about what had happened, and last week, the problem occurred again. I asked him about writing up the experience in a blog post, largely because of the red herrings that we encountered. It was an interesting experience for me, also because I didn’t end up touching my computer the whole time – just tapping on my phone via Twitter and Live Msgr. You see, the thing with replication is that a useful troubleshooting option is to reinitialise the thing. We’d done that last time, and it had started to work again – eventually. I say eventually, because the link being used between the sites is relatively slow, and it took a long while for the initialisation to finish. Meanwhile, we’d been doing some investigation into what the problem could be, and were suitably pleased when the problem disappeared. So I got a message saying that a replication problem had occurred again. Reinitialising wasn’t going to be an option this time either. In this scenario, the subscriber having the problem happened to be in a different domain to the publisher. The other subscribers (within the domain) were fine, just this one in a different domain had the problem. Part of the problem seemed to be a log file that wasn’t being backed up properly. They’d been trying to back up to a backup device that had a corruption, and the log file was growing. Turned out, this wasn’t related to the problem, but of course, any time you’re troubleshooting and you see something untoward, you wonder. Having got past that problem, my next thought was that perhaps there was a problem with the account being used. But the other subscribers were using the same account, without any problems. The client pointed out that that it was almost exactly six months since the last failure (later shown to be a complete red herring). It sounded like something might’ve expired. Checking through certificates and trusts showed no sign of anything, and besides, there wasn’t a problem running a command-prompt window using the account in question, from the subscriber box. ...except that when he ran the sqlcmd –E –S servername command I recommended, it failed with a Named Pipes error. I’ve seen problems with firewalls rejecting connections via Named Pipes but letting TCP/IP through, so I got him to look into SQL Configuration Manager to see what kind of connection was being preferred... Everything seemed fine. And strangely, he could connect via Management Studio. Turned out, he had a typo in the servername of the sqlcmd command. That particular red herring must’ve been reflected in his cheeks as he told me. During the time, I also pinged a friend of mine to find out who I should ask, and Ted Kruger (@onpnt) ‘s name came up. Ted (and thanks again, Ted – really) reconfirmed some of my thoughts around the idea of an account expiring, and also suggesting bumping up the logging to level 4 (2 is Verbose, 4 is undocumented ridiculousness). I’d just told the client to push the logging up to level 2, but the log file wasn’t appearing. Checking permissions showed that the user did have permission on the folder, but still no file was appearing. Then it was noticed that the user had been switched earlier as part of the troubleshooting, and switching it back to the real user caused the log file to appear. Still no errors. A lot more information being pushed out, but still no errors. Ted suggested making sure the FQDNs were okay from both ends, in case the servers were unable to talk to each other. DNS problems can lead to hassles which can stop replication from working. No luck there either – it was all working fine. Another server started to report a problem as well. These two boxes were both SQL 2008 R2 (SP1), while the others, still working, were SQL 2005. Around this time, the client tried an idea that I’d shown him a few years ago – using a Profiler trace to see what was being called on the servers. It turned out that the last call being made on the publisher was sp_MSenumschemachange. A quick interwebs search on that showed a problem that exists in SQL Server 2008 R2, when stored procedures have more than 4000 characters. Running that stored procedure (with the same parameters) manually on SQL 2005 listed three stored procedures, the first of which did indeed have more than 4000 characters. Still no error though, and the problem as listed at http://support.microsoft.com/kb/2539378 describes an error that should occur in the Event log. However, this problem is the type of thing that is fixed by a reinitialisation (because it doesn’t need to send the procedure change across as a transaction). And a look in the change history of the long stored procs (you all keep them, right?), showed that the problem from six months earlier could well have been down to this too. Applying SP2 (with sufficient paranoia about backups and how to get back out again if necessary) fixed the problem. The stored proc changes went through immediately after the service pack was applied, and it’s been running happily since. The funny thing is that I didn’t solve the problem. He had put the Profiler trace on the server, and had done the search that found a forum post pointing at this particular problem. I’d asked Ted too, and although he’d given some useful information, nothing that he’d come up with had actually been the solution either. Sometimes, asking for help is the most useful thing you can do. Often though, you don’t end up getting the help from the person you asked – the sounding board is actually what you need. @rob_farley

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  • Checking who is connected to your server, with PowerShell.

    - by Fatherjack
    There are many occasions when, as a DBA, you want to see who is connected to your SQL Server, along with how they are connecting and what sort of activities they are carrying out. I’m going to look at a couple of ways of getting this information and compare the effort required and the results achieved of each. SQL Server comes with a couple of stored procedures to help with this sort of task – sp_who and its undocumented counterpart sp_who2. There is also the pumped up version of these called sp_whoisactive, written by Adam Machanic which does way more than these procedures. I wholly recommend you try it out if you don’t already know how it works. When it comes to serious interrogation of your SQL Server activity then it is absolutely indispensable. Anyway, back to the point of this blog, we are going to look at getting the information from sp_who2 for a remote server. I wrote this Powershell script a week or so ago and was quietly happy with it for a while. I’m relatively new to Powershell so forgive both my rather low threshold for entertainment and the fact that something so simple is a moderate achievement for me. $Server = 'SERVERNAME' $SMOServer = New-Object Microsoft.SQLServer.Management.SMO.Server $Server # connection and query stuff         $ConnectionStr = "Server=$Server;Database=Master;Integrated Security=True" $Query = "EXEC sp_who2" $Connection = new-object system.Data.SQLClient.SQLConnection $Table = new-object "System.Data.DataTable" $Connection.connectionstring = $ConnectionStr try{ $Connection.open() $Command = $Connection.CreateCommand() $Command.commandtext = $Query $result = $Command.ExecuteReader() $Table.Load($result) } catch{ # Show error $error[0] | format-list -Force } $Title = "Data access processes (" + $Table.Rows.Count + ")" $Table | Out-GridView -Title $Title $Connection.close() So this is pretty straightforward, create an SMO object that represents our chosen server, define a connection to the database and a table object for the results when we get them, execute our query over the connection, load the results into our table object and then, if everything is error free display these results to the PowerShell grid viewer. The query simply gets the results of ‘EXEC sp_who2′ for us. Depending on how many connections there are will influence how long the query runs. The grid viewer lets me sort and search the results so it can be a pretty handy way to locate troublesome connections. Like I say, I was quite pleased with this, it seems a pretty simple script and was working well for me, I have added a few parameters to control the output and give me more specific details but then I see a script that uses the $SMOServer object itself to provide the process information and saves having to define the connection object and query specifications. $Server = 'SERVERNAME' $SMOServer = New-Object Microsoft.SQLServer.Management.SMO.Server $Server $Processes = $SMOServer.EnumProcesses() $Title = "SMO processes (" + $Processes.Rows.Count + ")" $Processes | Out-GridView -Title $Title Create the SMO object of our server and then call the EnumProcesses method to get all the process information from the server. Staggeringly simple! The results are a little different though. Some columns are the same and we can see the same basic information so my first thought was to which runs faster – so that I can get my results more quickly and also so that I place less stress on my server(s). PowerShell comes with a great way of testing this – the Measure-Command function. All you have to do is wrap your piece of code in Measure-Command {[your code here]} and it will spit out the time taken to execute the code. So, I placed both of the above methods of getting SQL Server process connections in two Measure-Command wrappers and pressed F5! The Powershell console goes blank for a while as the code is executed internally when Measure-Command is used but the grid viewer windows appear and the console shows this. You can take the output from Measure-Command and format it for easier reading but in a simple comparison like this we can simply cross refer the TotalMilliseconds values from the two result sets to see how the two methods performed. The query execution method (running EXEC sp_who2 ) is the first set of timings and the SMO EnumProcesses is the second. I have run these on a variety of servers and while the results vary from execution to execution I have never seen the SMO version slower than the other. The difference has varied and the time for both has ranged from sub-second as we see above to almost 5 seconds on other systems. This difference, I would suggest is partly due to the cost overhead of having to construct the data connection and so on where as the SMO EnumProcesses method has the connection to the server already in place and just needs to call back the process information. There is also the difference in the data sets to consider. Let’s take a look at what we get and where the two methods differ Query execution method (sp_who2) SMO EnumProcesses Description - Urn What looks like an XML or JSON representation of the server name and the process ID SPID Spid The process ID Status Status The status of the process Login Login The login name of the user executing the command HostName Host The name of the computer where the  process originated BlkBy BlockingSpid The SPID of a process that is blocking this one DBName Database The database that this process is connected to Command Command The type of command that is executing CPUTime Cpu The CPU activity related to this process DiskIO - The Disk IO activity related to this process LastBatch - The time the last batch was executed from this process. ProgramName Program The application that is facilitating the process connection to the SQL Server. SPID1 - In my experience this is always the same value as SPID. REQUESTID - In my experience this is always 0 - Name In my experience this is always the same value as SPID and so could be seen as analogous to SPID1 from sp_who2 - MemUsage An indication of the memory used by this process but I don’t know what it is measured in (bytes, Kb, Mb…) - IsSystem True or False depending on whether the process is internal to the SQL Server instance or has been created by an external connection requesting data. - ExecutionContextID In my experience this is always 0 so could be analogous to REQUESTID from sp_who2. Please note, these are my own very brief descriptions of these columns, detail can be found from MSDN for columns in the sp_who results here http://msdn.microsoft.com/en-GB/library/ms174313.aspx. Where the columns are common then I would use that description, in other cases then the information returned is purely for interpretation by the reader. Rather annoyingly both result sets have useful information that the other doesn’t. sp_who2 returns Disk IO and LastBatch information which is really useful but the SMO processes method give you IsSystem and MemUsage which have their place in fault diagnosis methods too. So which is better? On reflection I think I prefer to use the sp_who2 method primarily but knowing that the SMO Enumprocesses method is there when I need it is really useful and I’m sure I’ll use it regularly. I’m OK with the fact that it is the slower method because Measure-Command has shown me how close it is to the other option and that it really isn’t a large enough margin to matter.

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  • SQL SERVER – Repair a SQL Server Database Using a Transaction Log Explorer

    - by Pinal Dave
    In this blog, I’ll show how to use ApexSQL Log, a SQL Server transaction log viewer. You can download it for free, install, and play along. But first, let’s describe some disaster recovery scenarios where it’s useful. About SQL Server disaster recovery Along with database development and administration, you must work on a good recovery plan. Disasters do happen and no one’s immune. What you can do is take all actions needed to be ready for a disaster and go through it with minimal data loss and downtime. Besides creating a recovery plan, it’s necessary to have a list of steps that will be executed when a disaster occurs and to test them before a disaster. This way, you’ll know that the plan is good and viable. Testing can also be used as training for all team members, so they can all understand and execute it when the time comes. It will show how much time is needed to have your servers fully functional again and how much data you can lose in a real-life situation. If these don’t meet recovery-time and recovery-point objectives, the plan needs to be improved. Keep in mind that all major changes in environment configuration, business strategy, and recovery objectives require a new recovery plan testing, as these changes most probably induce a recovery plan changing and tweaking. What is a good SQL Server disaster recovery plan? A good SQL Server disaster recovery strategy starts with planning SQL Server database backups. An efficient strategy is to create a full database backup periodically. Between two successive full database backups, you can create differential database backups. It is essential is to create transaction log backups regularly between full database backups. Keep in mind that transaction log backups can be created only on databases in the full recovery model. In other words, a simple, but efficient backup strategy would be a full database backup every night, a transaction log backup every hour, or every 15 minutes. The frequency depends on how much data you can afford to lose and how busy the database is. Another option, instead of creating a full database backup every night, is to create a full database backup once a week (e.g. on Friday at midnight) and differential database backup every night until next Friday when you will create a full database backup again. Once you create your SQL Server database backup strategy, schedule the backups. You can do that easily using SQL Server maintenance plans. Why are transaction logs important? Transaction log backups contain transactions executed on a SQL Server database. They provide enough information to undo and redo the transactions and roll back or forward the database to a point in time. In SQL Server disaster recovery situations, transaction logs enable to repair a SQL Server database and bring it to the state before the disaster. Be aware that even with regular backups, there will be some data missing. These are the transactions made between the last transaction log backup and the time of the disaster. In some situations, to repair your SQL Server database it’s not necessary to re-create the database from its last backup. The database might still be online and all you need to do is roll back several transactions, such as wrong update, insert, or delete. The restore to a point in time feature is available in SQL Server, but for large databases, it is very time-consuming, as SQL Server first restores a full database backup, and then restores transaction log backups, one after another, up to the recovery point. During that time, the database is unavailable. This is where a SQL Server transaction log viewer can help. For optimal recovery, besides having a database in the full recovery model, it’s important that you haven’t manually truncated the online transaction log. This ensures that all transactions made after the last transaction log backup are still in the online transaction log. All you have to do is read and replay them. How to read a SQL Server transaction log? SQL Server doesn’t provide an option to read transaction logs. There are several SQL Server commands and functions that read the content of a transaction log file (fn_dblog, fn_dump_dblog, and DBCC PAGE), but they are undocumented. They require T-SQL knowledge, return a large number of not easy to read and understand columns, sometimes in binary or hexadecimal format. Another challenge is reading UPDATE statements, as it’s necessary to match it to a value in the MDF file. When you finally read the transactions executed, you have to create a script for it. How to easily repair a SQL database? The easiest solution is to use a transaction log reader that will not only read the transactions in the transaction log files, but also automatically create scripts for the read transactions. In the following example, I will show how to use ApexSQL Log to repair a SQL database after a crash. If a database has crashed and both MDF and LDF files are lost, you have to rely on the full database backup and all subsequent transaction log backups. In another scenario, the MDF file is lost, but the LDF file is available. First, restore the last full database backup on SQL Server using SQL Server Management Studio. I’ll name it Restored_AW2014. Then, start ApexSQL Log It will automatically detect all local servers. If not, click the icon right to the Server drop-down list, or just type in the SQL Server instance name. Select the Windows or SQL Server authentication type and select the Restored_AW2014 database from the database drop-down list. When all options are set, click Next. ApexSQL Log will show the online transaction log file. Now, click Add and add all transaction log backups created after the full database backup I used to restore the database. In case you don’t have transaction log backups, but the LDF file hasn’t been lost during the SQL Server disaster, add it using Add.   To repair a SQL database to a point in time, ApexSQL Log needs to read and replay all the transactions in the transaction log backups (or the LDF file saved after the disaster). That’s why I selected the Whole transaction log option in the Filter setup. ApexSQL Log offers a range of various filters, which are useful when you need to read just specific transactions. You can filter transactions by the time of the transactions, operation type (e.g. to read only data inserts), table name, SQL Server login that made the transaction, etc. In this scenario, to repair a SQL database, I’ll check all filters and make sure that all transactions are included. In the Operations tab, select all schema operations (DDL). If you omit these, only the data changes will be read so if there were any schema changes, such as a new function created, or an existing table modified, they will be ignored and database will not be properly repaired. The data repair for modified tables will fail. In the Tables tab, I’ll make sure all tables are selected. I will uncheck the Show operations on dropped tables option, to reduce the number of transactions. Click Next. ApexSQL Log offers three options. Select Open results in grid, to get a user-friendly presentation of the transactions. As you can see, details are shown for every transaction, including the old and new values for updated columns, which are clearly highlighted. Now, select them all and then create a redo script by clicking the Create redo script icon in the menu.   For a large number of transactions and in a critical situation, when acting fast is a must, I recommend using the Export results to file option. It will save some time, as the transactions will be directly scripted into a redo file, without showing them in the grid first. Select Generate reconstruction (REDO) script , change the output path if you want, and click Finish. After the redo T-SQL script is created, ApexSQL Log shows the redo script summary: The third option will create a command line statement for a batch file that you can use to schedule execution, which is not really applicable when you repair a SQL database, but quite useful in daily auditing scenarios. To repair your SQL database, all you have to do is execute the generated redo script using an integrated developer environment tool such as SQL Server Management Studio or any other, against the restored database. You can find more information about how to read SQL Server transaction logs and repair a SQL database on ApexSQL Solution center. There are solutions for various situations when data needs to be recovered, restored, or transactions rolled back. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • Hello Operator, My Switch Is Bored

    - by Paul White
    This is a post for T-SQL Tuesday #43 hosted by my good friend Rob Farley. The topic this month is Plan Operators. I haven’t taken part in T-SQL Tuesday before, but I do like to write about execution plans, so this seemed like a good time to start. This post is in two parts. The first part is primarily an excuse to use a pretty bad play on words in the title of this blog post (if you’re too young to know what a telephone operator or a switchboard is, I hate you). The second part of the post looks at an invisible query plan operator (so to speak). 1. My Switch Is Bored Allow me to present the rare and interesting execution plan operator, Switch: Books Online has this to say about Switch: Following that description, I had a go at producing a Fast Forward Cursor plan that used the TOP operator, but had no luck. That may be due to my lack of skill with cursors, I’m not too sure. The only application of Switch in SQL Server 2012 that I am familiar with requires a local partitioned view: CREATE TABLE dbo.T1 (c1 int NOT NULL CHECK (c1 BETWEEN 00 AND 24)); CREATE TABLE dbo.T2 (c1 int NOT NULL CHECK (c1 BETWEEN 25 AND 49)); CREATE TABLE dbo.T3 (c1 int NOT NULL CHECK (c1 BETWEEN 50 AND 74)); CREATE TABLE dbo.T4 (c1 int NOT NULL CHECK (c1 BETWEEN 75 AND 99)); GO CREATE VIEW V1 AS SELECT c1 FROM dbo.T1 UNION ALL SELECT c1 FROM dbo.T2 UNION ALL SELECT c1 FROM dbo.T3 UNION ALL SELECT c1 FROM dbo.T4; Not only that, but it needs an updatable local partitioned view. We’ll need some primary keys to meet that requirement: ALTER TABLE dbo.T1 ADD CONSTRAINT PK_T1 PRIMARY KEY (c1);   ALTER TABLE dbo.T2 ADD CONSTRAINT PK_T2 PRIMARY KEY (c1);   ALTER TABLE dbo.T3 ADD CONSTRAINT PK_T3 PRIMARY KEY (c1);   ALTER TABLE dbo.T4 ADD CONSTRAINT PK_T4 PRIMARY KEY (c1); We also need an INSERT statement that references the view. Even more specifically, to see a Switch operator, we need to perform a single-row insert (multi-row inserts use a different plan shape): INSERT dbo.V1 (c1) VALUES (1); And now…the execution plan: The Constant Scan manufactures a single row with no columns. The Compute Scalar works out which partition of the view the new value should go in. The Assert checks that the computed partition number is not null (if it is, an error is returned). The Nested Loops Join executes exactly once, with the partition id as an outer reference (correlated parameter). The Switch operator checks the value of the parameter and executes the corresponding input only. If the partition id is 0, the uppermost Clustered Index Insert is executed, adding a row to table T1. If the partition id is 1, the next lower Clustered Index Insert is executed, adding a row to table T2…and so on. In case you were wondering, here’s a query and execution plan for a multi-row insert to the view: INSERT dbo.V1 (c1) VALUES (1), (2); Yuck! An Eager Table Spool and four Filters! I prefer the Switch plan. My guess is that almost all the old strategies that used a Switch operator have been replaced over time, using things like a regular Concatenation Union All combined with Start-Up Filters on its inputs. Other new (relative to the Switch operator) features like table partitioning have specific execution plan support that doesn’t need the Switch operator either. This feels like a bit of a shame, but perhaps it is just nostalgia on my part, it’s hard to know. Please do let me know if you encounter a query that can still use the Switch operator in 2012 – it must be very bored if this is the only possible modern usage! 2. Invisible Plan Operators The second part of this post uses an example based on a question Dave Ballantyne asked using the SQL Sentry Plan Explorer plan upload facility. If you haven’t tried that yet, make sure you’re on the latest version of the (free) Plan Explorer software, and then click the Post to SQLPerformance.com button. That will create a site question with the query plan attached (which can be anonymized if the plan contains sensitive information). Aaron Bertrand and I keep a close eye on questions there, so if you have ever wanted to ask a query plan question of either of us, that’s a good way to do it. The problem The issue I want to talk about revolves around a query issued against a calendar table. The script below creates a simplified version and adds 100 years of per-day information to it: USE tempdb; GO CREATE TABLE dbo.Calendar ( dt date NOT NULL, isWeekday bit NOT NULL, theYear smallint NOT NULL,   CONSTRAINT PK__dbo_Calendar_dt PRIMARY KEY CLUSTERED (dt) ); GO -- Monday is the first day of the week for me SET DATEFIRST 1;   -- Add 100 years of data INSERT dbo.Calendar WITH (TABLOCKX) (dt, isWeekday, theYear) SELECT CA.dt, isWeekday = CASE WHEN DATEPART(WEEKDAY, CA.dt) IN (6, 7) THEN 0 ELSE 1 END, theYear = YEAR(CA.dt) FROM Sandpit.dbo.Numbers AS N CROSS APPLY ( VALUES (DATEADD(DAY, N.n - 1, CONVERT(date, '01 Jan 2000', 113))) ) AS CA (dt) WHERE N.n BETWEEN 1 AND 36525; The following query counts the number of weekend days in 2013: SELECT Days = COUNT_BIG(*) FROM dbo.Calendar AS C WHERE theYear = 2013 AND isWeekday = 0; It returns the correct result (104) using the following execution plan: The query optimizer has managed to estimate the number of rows returned from the table exactly, based purely on the default statistics created separately on the two columns referenced in the query’s WHERE clause. (Well, almost exactly, the unrounded estimate is 104.289 rows.) There is already an invisible operator in this query plan – a Filter operator used to apply the WHERE clause predicates. We can see it by re-running the query with the enormously useful (but undocumented) trace flag 9130 enabled: Now we can see the full picture. The whole table is scanned, returning all 36,525 rows, before the Filter narrows that down to just the 104 we want. Without the trace flag, the Filter is incorporated in the Clustered Index Scan as a residual predicate. It is a little bit more efficient than using a separate operator, but residual predicates are still something you will want to avoid where possible. The estimates are still spot on though: Anyway, looking to improve the performance of this query, Dave added the following filtered index to the Calendar table: CREATE NONCLUSTERED INDEX Weekends ON dbo.Calendar(theYear) WHERE isWeekday = 0; The original query now produces a much more efficient plan: Unfortunately, the estimated number of rows produced by the seek is now wrong (365 instead of 104): What’s going on? The estimate was spot on before we added the index! Explanation You might want to grab a coffee for this bit. Using another trace flag or two (8606 and 8612) we can see that the cardinality estimates were exactly right initially: The highlighted information shows the initial cardinality estimates for the base table (36,525 rows), the result of applying the two relational selects in our WHERE clause (104 rows), and after performing the COUNT_BIG(*) group by aggregate (1 row). All of these are correct, but that was before cost-based optimization got involved :) Cost-based optimization When cost-based optimization starts up, the logical tree above is copied into a structure (the ‘memo’) that has one group per logical operation (roughly speaking). The logical read of the base table (LogOp_Get) ends up in group 7; the two predicates (LogOp_Select) end up in group 8 (with the details of the selections in subgroups 0-6). These two groups still have the correct cardinalities as trace flag 8608 output (initial memo contents) shows: During cost-based optimization, a rule called SelToIdxStrategy runs on group 8. It’s job is to match logical selections to indexable expressions (SARGs). It successfully matches the selections (theYear = 2013, is Weekday = 0) to the filtered index, and writes a new alternative into the memo structure. The new alternative is entered into group 8 as option 1 (option 0 was the original LogOp_Select): The new alternative is to do nothing (PhyOp_NOP = no operation), but to instead follow the new logical instructions listed below the NOP. The LogOp_GetIdx (full read of an index) goes into group 21, and the LogOp_SelectIdx (selection on an index) is placed in group 22, operating on the result of group 21. The definition of the comparison ‘the Year = 2013’ (ScaOp_Comp downwards) was already present in the memo starting at group 2, so no new memo groups are created for that. New Cardinality Estimates The new memo groups require two new cardinality estimates to be derived. First, LogOp_Idx (full read of the index) gets a predicted cardinality of 10,436. This number comes from the filtered index statistics: DBCC SHOW_STATISTICS (Calendar, Weekends) WITH STAT_HEADER; The second new cardinality derivation is for the LogOp_SelectIdx applying the predicate (theYear = 2013). To get a number for this, the cardinality estimator uses statistics for the column ‘theYear’, producing an estimate of 365 rows (there are 365 days in 2013!): DBCC SHOW_STATISTICS (Calendar, theYear) WITH HISTOGRAM; This is where the mistake happens. Cardinality estimation should have used the filtered index statistics here, to get an estimate of 104 rows: DBCC SHOW_STATISTICS (Calendar, Weekends) WITH HISTOGRAM; Unfortunately, the logic has lost sight of the link between the read of the filtered index (LogOp_GetIdx) in group 22, and the selection on that index (LogOp_SelectIdx) that it is deriving a cardinality estimate for, in group 21. The correct cardinality estimate (104 rows) is still present in the memo, attached to group 8, but that group now has a PhyOp_NOP implementation. Skipping over the rest of cost-based optimization (in a belated attempt at brevity) we can see the optimizer’s final output using trace flag 8607: This output shows the (incorrect, but understandable) 365 row estimate for the index range operation, and the correct 104 estimate still attached to its PhyOp_NOP. This tree still has to go through a few post-optimizer rewrites and ‘copy out’ from the memo structure into a tree suitable for the execution engine. One step in this process removes PhyOp_NOP, discarding its 104-row cardinality estimate as it does so. To finish this section on a more positive note, consider what happens if we add an OVER clause to the query aggregate. This isn’t intended to be a ‘fix’ of any sort, I just want to show you that the 104 estimate can survive and be used if later cardinality estimation needs it: SELECT Days = COUNT_BIG(*) OVER () FROM dbo.Calendar AS C WHERE theYear = 2013 AND isWeekday = 0; The estimated execution plan is: Note the 365 estimate at the Index Seek, but the 104 lives again at the Segment! We can imagine the lost predicate ‘isWeekday = 0’ as sitting between the seek and the segment in an invisible Filter operator that drops the estimate from 365 to 104. Even though the NOP group is removed after optimization (so we don’t see it in the execution plan) bear in mind that all cost-based choices were made with the 104-row memo group present, so although things look a bit odd, it shouldn’t affect the optimizer’s plan selection. I should also mention that we can work around the estimation issue by including the index’s filtering columns in the index key: CREATE NONCLUSTERED INDEX Weekends ON dbo.Calendar(theYear, isWeekday) WHERE isWeekday = 0 WITH (DROP_EXISTING = ON); There are some downsides to doing this, including that changes to the isWeekday column may now require Halloween Protection, but that is unlikely to be a big problem for a static calendar table ;)  With the updated index in place, the original query produces an execution plan with the correct cardinality estimation showing at the Index Seek: That’s all for today, remember to let me know about any Switch plans you come across on a modern instance of SQL Server! Finally, here are some other posts of mine that cover other plan operators: Segment and Sequence Project Common Subexpression Spools Why Plan Operators Run Backwards Row Goals and the Top Operator Hash Match Flow Distinct Top N Sort Index Spools and Page Splits Singleton and Range Seeks Bitmaps Hash Join Performance Compute Scalar © 2013 Paul White – All Rights Reserved Twitter: @SQL_Kiwi

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