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  • When does "proper" programming no longer matter?

    - by Kai Qing
    I've been a full time programmer for about 8 years now. Web based mostly, ranging in weird jobs for clients. Never anything I "want" to do. So my experience is limited to what I've been contracted to do, having no real incentive to master anything in particular. So here's my scenario and ultimately what I wonder about... I've been building an android game in my spare time. It's using the libgdx library so quite a bit of the heavy lifting is done for me. I don't read much of the docs cause unless it's in tutorial format I will just not care, and ultimately most of my questions have already been asked on stackoverflow. I get along fine and my game works as expected... Suspiciously well, even. So much so that I wonder why one should bother to be "proper" when coding if the end result is ultimately the same. To be more specific, I used a hashtable because I wanted something close to an associative array. Human readable key values. In other places to achieve similar things, I use a vector. I know libgdx has vector2 and vector3 classes, but I've never used them. When I come across weird problems and search stackoverflow for help, I see a lot of people just reaming the questions that use a certain datatype when another one is technically "proper." Like using an ArrayList because it does not require defined bounds versus re-defining an int[] with new known boundaries. Or even something trivial like this: for(int i = 0; i < items.length; i ++) { // do something } I know it evaluates item.length on every iteration. I just don't care. I know items will never be more than 15 to 20 items. So why bother caring if I evaluate items.length on every iteration? So I wonder - why does everyone get all up in arms over this? Who cares if I use a less efficient datatype to get the job done? I ran some tests to see how the app performs using the lazy, get it done fast and don't look back method I just described versus the proper, follow the tutorial and use the exact data types suggested by the community. The results: Same thing. Average 45 fps. I opened every app on the phone and galaxy tab. Same deal. No difference. My game is pretty graphic intensive. It's not like it's just a simple thing. I expected it to perform kind of badly since I don't care to optimize image assets or... well, you probably get the idea. I'm making the game for fun. As a joke, really. But in doing so I'm working outside the normal scope of my job, which is to always follow the rules and do it the right way. So to say, I am without bounds here and this has caused me to wonder why I ever really care to be "proper" So I guess my question to you is this: Is there a threshold when it no longer matters to be proper? Is there a lasting, longer term consequence to the lazy, get it done and don't look back route? Is it ok to say - "so long as it gets the job done, I don't care?" Disclaimer: When I program my game, I am almost always drunk. I do it to remember why I got into this stuff to begin with because the monotony of client based web work will make you hate being a programmer. I'm having a blast and my game is not crashing, tests well, performs well, looks good on all devices so far and has no noticeable negative impact on any of my testing devices. I expected failure because I was being so drunkenly careless with my code, but to my surprise, it had no noticeable impact. I am now starting to question the need to be careful. Help me regain the ability to care! ... or explain why it's not a bad thing to not care. Secondary disclaimer: I am aware of the benefits of maintainability. For myself and others. Agreed. But it's not like someone happening across my inefficient int[] loop won't know what it does. As an experienced programmer those kinds of things are just clear on sight. I document the complex stuff for myself knowing I was drunk and will probably need a reminder. Those notes would clarify any confusion for someone who might ever gaze upon my ridiculous game - though the reality is that either I maintain it myself or it fades into time. I'm ok with that. But if it doesn't slow the device down, or crash, then crossing the t's and dotting the i's might actually require more time than it's worth.

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  • Handbrake-powered VidCoder gets a native 64-bit version

    A while back, VidCoder -- the Windows video disc ripping program -- added support for Blu-ray discs. With Handbrake's engine under the hood, VidCoder offers an easy-to-use interface and simple batch processing of your video files. With the release of version 0.8, there's also now a native 64-bit version for those of you running Windows x64. A number of stability tweaks have also been introduced. As Baz pointed out in our comments last time, VidCoder is particular useful on netbooks. If you've got a 1024x600 screen, Handbrake may not even launch for you -- but VidCoder will fire up just fine. Take the new 64-bit version for a spin, and share your thoughts in the comments. Download VidCoderHandbrake-powered VidCoder gets a native 64-bit version originally appeared on Download Squad on Fri, 07 Jan 2011 17:00:00 EST. Please see our terms for use of feeds.Permalink | Email this | Comments

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  • How do I Set PATH in /etc/profile.d?

    - by Rodrigo Sasaki
    I'm using zsh as my shell, and I'm trying to configure my environment. I usually define my $JAVA_HOME variable by creating a file: /etc/profile.d/java.sh with the following content export JAVA_HOME=/path/to/jdk export PATH=$JAVA_HOME/bin:$PATH then I logout and back in, and it all works, but for some reason the PATH variable is not set. It recognizes JAVA_HOME, but not the new PATH, see this terminal snippet: ~ echo $JAVA_HOME /usr/lib/jvm/jdk1.8.0_05 ~ echo $PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games and I confirmed it by trying to run a command form the jvm ~ java -version zsh: command not found: java the PATH doesn't include the $JAVA_HOME as it should. is there something else I should check? EDIT I have checked that if I run source /etc/profile.d/java.sh it all runs correctly and my variables get set as they should, but shouldn't the scripts in /etc/profile.d run automatically?

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  • Maintain proper symbol order when applying an armature in flash

    - by Michael Taufen
    I am trying to animate a character's leg in flash CS 5.5 for a game I am working on. I decided to use the bone tool because it's awesome. The problem I am having, however, is that for my character to be animated properly, the symbols that make up his leg (upper leg, lower leg, and shoe) need to be on top of each other in a specific way (otherwise the shoe looks like its next to the leg, etc). Applying the bones results in the following problem: the first symbol I apply it to is placed in the rear on the armature layer, the next on top of it, and so on, until the final symbol is already on top. I need them to be in the opposite order, but arrange send to back does nothing on the armature layer. How can I fix this? tl;dr: The bone tool is not maintaining the stacking order of my objects, please help. Thanks for helping :).

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  • Gnome, Desktop, Gui, Menu Panel : Upgrading from 10.04 to 11.04

    - by Avukonke Peter
    After upgrading from ubuntu 10.04 to ubuntu 11.04, my gnome (Desktop) is completely messed up. Because I was hesitant to remove all the packages that were on y desktop. I chose to keep all the dependent files during my upgrade to Ubuntu 11.04. After the upgrade my GUI is simply not working. I think it's because of the conflicting files that I choose to keep while upgrading. I can launch nautilus manually,but still I don't have access to any of the menus available in ubuntu. Is there a way I can upgrade from 11.04 to 11.10 and restore my GUI. I tried to upgrade using aptitude, but it doesn't detect the latest ubuntu release, is there a way I can specify where to find the latest release as well get my GUI back ?

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  • how to do partial updates in OpenGL?

    - by Will
    It is general wisdom that you redraw the entire viewport on each frame. I would like to use partial updates; what are the various ways can do that, and what are their pros, cons and relative performance? (Using textures, FBOs, the accumulator buffer, any kind of scissors that can affect swapbuffers etc?) A scenario: a scene with a fair few thousand visible trees; although the textures are mipmapped and they are drawn via VBOs roughly front-to-back with so on, its still a lot of polys. Would streaming a single screen-sized texture be better than throwing them at the screen every frame? You'd have to redraw and recapture them only on camera movement or as often as your wind model updates or whatever, which need not be every frame.

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  • Invisible boundary on Synergy client

    - by Jayson Rowe
    I have a Desktop system (named 'desktop') with 2 monitors attached (one 1680x1050 and another 1920x1080 resolution), running a synergy server. I also have a small ITX machine (named 'tiny') to my right that has a single monitor running at 1280x1024. The dual-monitor desktop is the synergy "server" and the single monitor system is the "client". Synergy works fine with one exception; if I move the mouse to the client, I can't move my mouse below the top two-thirds of the screen - it just stops. I can grab a mouse attached to the computer, and it moves all the way down, but as soon as I touch the mouse attached to the server, it jumps back to the top of the screen. Is there an issue with my config? section: screens desktop: tiny: end section: links desktop: right = tiny tiny: left = desktop end Thanks in advance for any suggestions. +----------------------------+-----------------------------+ | | | | | | | | +-----------------+ | | | | | desktop 1680x1050 | desktop 1920x1080 | | | | | | | | | tiny 1280x1024 | | | |+---------------+| | | |XXXXXXXXXXXXXXXXX| +----------------------------+-----------------------------+-----------------+

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  • Apple Announces iPad 2 Event On March 2

    - by Gopinath
    All those holy rumours about iPad 2 (or what ever the new device is going to be called) launch in the next week are true. Apple has sent a media event invite to prominent blogs and media guys. Here is the invitation Image looks like unwrapping of iPad 2 right? Very obvious. But the details of hardware and new features of next version of iPad are very secret. According to the rumours it may have – front & back camera, Facetime, Retina Display, NFC, 7″ ipads and thinner iPads. These are all the rumours we are hearing for the past 1 month. Only on March 2nd we can get to know the actual details. Till then keep reading the rumours This article titled,Apple Announces iPad 2 Event On March 2, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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  • I think I killed my portable HD will trying to make Ubuntu bootable from it. How to undo?

    - by Jack
    I have OSX. My HD appears as two drives; one formatted for OSX, and the other FAT32 for everything. Note: I am a complete Terminal noob. I followed the How to create a bootable USB stick on OS X page. I installed it to the Mac formatted partition, which I'm 95% sure was a mistake. I was thinking more in terms of free space than proper format. Anyway, it doesn't boot, and I can't get the HD to appear when I plug it back into OSX. I have no idea how to undo what I did in Terminal. Any ideas?

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  • ATI Proprietary Driver Over/Underscan setting ignored after reboot

    - by Lassi
    I installed the proprietary driver (fglrx-updates) on Ubuntu 12.10 64-bit for my graphics card (ATI Radeon HD 7570). I am using two displays, one connected with DVI, one with HDMI. I set the desktop to be expanded to both screens and disabled the under scan for the HDMI screen, which is always for some reason enabled on HDMI screens. Now the issue. Everything was fine until I restarted my computer. After reboot, the screen connected with HDMI cable had the black borders again, meaning that the under scan is again enabled. I checked the ATI CCC, and under scan was disabled. However, moving the slider to enable under scan and then back to zero fixed the issue -- temporarily. The same issue is repeated every time I restart my computer. The settings remains the same, but the computer seems to ignore it. Any ideas how I could solve the issue?

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  • Why can't I upgrade my kernel via the terminal?

    - by Alvar
    If I type sudo apt-get update && sudo apt-get upgrade I can only see that the kernel packages are kept back, and not installed. As the screenshot shows. If I then start the update manager I can install the kernel, with no problems at all. As the second screenshot shows. Why is this? The kernel is a new package and not an upgrade of an old one, this is why you can't use the command upgrade that upgrades packages. You need to use the command dist-upgrade to install new packages.

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  • Is php|architect any good?

    - by Andrew Heath
    Kind of a hard topic to search for, as architect turns up a lot about software architects instead. After 8 months of PHP self-study, I finally stumbled across the php|architect site. The length of time it took me to find it makes me suspicious of its quality. 3 related questions: do professional PHP coders read/care about php|architect? is it a good source for PHP beginners? assuming yes to either of the above, how far back in the archives to articles remain relevant? (ex: does stuff written about PHP4 still matter?)

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  • Why does the MaxReceiveMessageSize in WCF matter in case of Streaming

    The default value of MaxReceiveMessageSize in WCF is 65,536.  When you choose streaming as TransferMode, WCF runtime will create 8192 as buffer size. So what happened now is that WCF channel stack will read the first 8192 bytes, and decode the first couple of bytes as the size of the entire envelope. Then we will do a size check, and send back fault if the actual size exceeds the limit.   According to MSDN documentation, the MaxReceiveMessageSize is something that prevents a DOS attack,...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Ubuntu 12.04 Boot Error

    - by Aman
    My Laptop was working just fine a day back but it started show the following error on booting: error: couldn't read file So, I googled about it and used a Live-CD to use Boot-Repair as told here: "can't read file" error after installation causes system to not boot I was given this link: http://paste.ubuntu.com/1441528/ if there are issues still. I also tried to do it again by a Boot-Repair-Disk this time and now I am getting the following error: error: couldn't read file error: you need to load the kernel first The boot-repair-disk gave me this link: http://paste2.org/p/2609703 if there are further issues.

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  • Is php|architect any good?

    - by Andrew Heath
    Kind of a hard topic to search for, as architect turns up a lot about software architects instead. After 8 months of PHP self-study, I finally stumbled across the php|architect site. The length of time it took me to find it makes me suspicious of its quality. 3 related questions: do professional PHP coders read/care about php|architect? is it a good source for PHP beginners? assuming yes to either of the above, how far back in the archives to articles remain relevant? (ex: does stuff written about PHP4 still matter?)

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  • Columnstore Case Study #2: Columnstore faster than SSAS Cube at DevCon Security

    - by aspiringgeek
    Preamble This is the second in a series of posts documenting big wins encountered using columnstore indexes in SQL Server 2012 & 2014.  Many of these can be found in my big deck along with details such as internals, best practices, caveats, etc.  The purpose of sharing the case studies in this context is to provide an easy-to-consume quick-reference alternative. See also Columnstore Case Study #1: MSIT SONAR Aggregations Why Columnstore? As stated previously, If we’re looking for a subset of columns from one or a few rows, given the right indexes, SQL Server can do a superlative job of providing an answer. If we’re asking a question which by design needs to hit lots of rows—DW, reporting, aggregations, grouping, scans, etc., SQL Server has never had a good mechanism—until columnstore. Columnstore indexes were introduced in SQL Server 2012. However, they're still largely unknown. Some adoption blockers existed; yet columnstore was nonetheless a game changer for many apps.  In SQL Server 2014, potential blockers have been largely removed & they're going to profoundly change the way we interact with our data.  The purpose of this series is to share the performance benefits of columnstore & documenting columnstore is a compelling reason to upgrade to SQL Server 2014. The Customer DevCon Security provides home & business security services & has been in business for 135 years. I met DevCon personnel while speaking to the Utah County SQL User Group on 20 February 2012. (Thanks to TJ Belt (b|@tjaybelt) & Ben Miller (b|@DBADuck) for the invitation which serendipitously coincided with the height of ski season.) The App: DevCon Security Reporting: Optimized & Ad Hoc Queries DevCon users interrogate a SQL Server 2012 Analysis Services cube via SSRS. In addition, the SQL Server 2012 relational back end is the target of ad hoc queries; this DW back end is refreshed nightly during a brief maintenance window via conventional table partition switching. SSRS, SSAS, & MDX Conventional relational structures were unable to provide adequate performance for user interaction for the SSRS reports. An SSAS solution was implemented requiring personnel to ramp up technically, including learning enough MDX to satisfy requirements. Ad Hoc Queries Even though the fact table is relatively small—only 22 million rows & 33GB—the table was a typical DW table in terms of its width: 137 columns, any of which could be the target of ad hoc interrogation. As is common in DW reporting scenarios such as this, it is often nearly to optimize for such queries using conventional indexing. DevCon DBAs & developers attended PASS 2012 & were introduced to the marvels of columnstore in a session presented by Klaus Aschenbrenner (b|@Aschenbrenner) The Details Classic vs. columnstore before-&-after metrics are impressive. Scenario Conventional Structures Columnstore ? SSRS via SSAS 10 - 12 seconds 1 second >10x Ad Hoc 5-7 minutes (300 - 420 seconds) 1 - 2 seconds >100x Here are two charts characterizing this data graphically.  The first is a linear representation of Report Duration (in seconds) for Conventional Structures vs. Columnstore Indexes.  As is so often the case when we chart such significant deltas, the linear scale doesn’t expose some the dramatically improved values corresponding to the columnstore metrics.  Just to make it fair here’s the same data represented logarithmically; yet even here the values corresponding to 1 –2 seconds aren’t visible.  The Wins Performance: Even prior to columnstore implementation, at 10 - 12 seconds canned report performance against the SSAS cube was tolerable. Yet the 1 second performance afterward is clearly better. As significant as that is, imagine the user experience re: ad hoc interrogation. The difference between several minutes vs. one or two seconds is a game changer, literally changing the way users interact with their data—no mental context switching, no wondering when the results will appear, no preoccupation with the spinning mind-numbing hurry-up-&-wait indicators.  As we’ve commonly found elsewhere, columnstore indexes here provided performance improvements of one, two, or more orders of magnitude. Simplified Infrastructure: Because in this case a nonclustered columnstore index on a conventional DW table was faster than an Analysis Services cube, the entire SSAS infrastructure was rendered superfluous & was retired. PASS Rocks: Once again, the value of attending PASS is proven out. The trip to Charlotte combined with eager & enquiring minds let directly to this success story. Find out more about the next PASS Summit here, hosted this year in Seattle on November 4 - 7, 2014. DevCon BI Team Lead Nathan Allan provided this unsolicited feedback: “What we found was pretty awesome. It has been a game changer for us in terms of the flexibility we can offer people that would like to get to the data in different ways.” Summary For DW, reports, & other BI workloads, columnstore often provides significant performance enhancements relative to conventional indexing.  I have documented here, the second in a series of reports on columnstore implementations, results from DevCon Security, a live customer production app for which performance increased by factors of from 10x to 100x for all report queries, including canned queries as well as reducing time for results for ad hoc queries from 5 - 7 minutes to 1 - 2 seconds. As a result of columnstore performance, the customer retired their SSAS infrastructure. I invite you to consider leveraging columnstore in your own environment. Let me know if you have any questions.

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  • SQLAuthority News MSDN Flash Mentions TechNet Flash Mention Top Community Contributors (Annual) W

    I was going over my email to reach the famous Inbox(0), I found TechNet Flash and MSDN Flash email. I had kept them because those email editions had mentioned me in the same. I quickly took the screenshot for the same. I am posting them here to refer them back again. It is always good [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Only MPV format available in HandBrake

    - by Steve Ellis
    I am running Ubuntu 14.04 LTS 32 bit. I have installed HandBrake rev5474 (i686), which I believe is the latest, and the Ubuntu Restricted Extras. I am able to play DVDs via VLC but when it comes to ripping them, so that I can back them up to my Twonky media server, I have issues. I launch HandBrake and find that the only format available for me to select is MPV. When I used to run Handbrake on this machine while I was running Ubuntu 13.10 and lower I had no issues and **lots of formats (including MP4 which is what I'm really after) but since reformating and installing 14.04 I've had this issue. Any help would be much appreciated.

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  • How to configure permanent autologin?

    - by DanielGibbs
    I'm trying to set up an Ubuntu 12.04 machine as a kiosk and I would like it, on boot, to automatically log in as my kiosk user "kiosk", and start the appropriate display manager, in this case blackbox. I have configured /etc/lightdm/lightdm.conf as in this question and have an appropriate /usr/share/xsessions/blackbox.desktop to launch blackbox. I managed to get initial autologin by using the dbus-send method in this question, however if I right-click and select "Exit" from blackbox, then I am taken back to the login screen. How can I configure lightdm/ubuntu to always autologin as "kiosk" instead of displaying the login screen? Or, failing that, how can I configure blackbox to not display a menu when I right-click?

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  • How do I fix my locale issue?

    - by HackToHell
    I am getting this message everytime I do something like starting or stopping a service. perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = "en_US:en", LC_ALL = (unset), LC_MESSAGES = "en_US.UTF-8", LANG = "en_US.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory (Reading database ... 21173 files and directories currently installed.) Removing bind9 ... * Stopping domain name service... bind9 [ OK ] Processing triggers for man-db ... locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory How do I fix this error ?

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  • What You Said: Your Favorite Windows Customization Tricks

    - by Jason Fitzpatrick
    Earlier this week we asked you to share your favorite Windows customization tricks and now we’re back to highlight some of the tips, tricks, and tweaks you shared. Your customization tips ranged from cosmetic to behind the scenes tweaks and offered a wide variety of ways to customize the Windows experience. Ted Lilley’s favorite must-have tweak involves Windows Explorer: The most fundamental change I make to Windows 7 is to immediately add tabs to Explorer via the QTTabbar add-on. I also add the good old cut/copy/paste/delete/new folder buttons alongside the tabs by installing Classic Shell (I skip Classic Start). Robin sets up virtual desktops: How to Use an Xbox 360 Controller On Your Windows PC Download the Official How-To Geek Trivia App for Windows 8 How to Banish Duplicate Photos with VisiPic

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  • Google Analytics conversion tracking - referrals from payment provider

    - by martynas
    I have a question regarding conversion tracking using Google Analytics. My client uses an external payment service provider - SecureTrading. Problem: All website visitors who would like to make a purchase are taken to a payment form on https://securetrading.net and are redirected back after a successful payment. Google Analytics counts that as a referral and messes up conversion tracking stats. Question: What needs to be changed / added in the payment forms or Google Analytics settings so that the conversions would be assigned to the right traffic sources. Screenshot:

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  • SQLMidlands & SQLLunch

    - by Dave Ballantyne
    Many thanks to all those that turned out to see my presentation on Thursday (16th of Feb) of “Cursors are Evil” at SQLMidlands.  The scripts i used are here : https://skydrive.live.com/?cid=4004b6a3bc887e2c&id=4004B6A3BC887E2C%21216 You will need the AdventureWorks2008r2 release to run these, feel free to mail me ([email protected]) with any questions.  They are based upon a series of articles I wrote for SQLServerCentral which can be found here and here. Also I am starting ,or at least having an attempt at, a new user group in London.  This is SQLLunch, meeting downstairs at The Golden Fleece , EC4N 1SP which is 2 minutes from Bank Tube , we will have a twice monthly meeting (2nd and 4th Tuesdays) for an ‘All Stuff, No Fluff’ event.  Put plainly, a quick hello followed by a 45 minute presentation , which will ,optimistically, have you there and back to your desk within a lunch hour. Registrations for the first series of dates are at sqlserverfaq.com If you would like to speak, then please get in touch. Hope to see you there. 

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  • SQL SERVER – Enable PowerPivot Plugin in Excel

    - by pinaldave
    Recently I had interesting experience at one conference. My PowerPivot plugin got disabled and I had no clue how to enable the same. After while, I figured out how to enable the same. Once I got back from the event, I searched online and realize that many other people online are facing the same problem. Here is how I solved the problem. When I started Excel it did not load PowerPivot plugin. I found in option>> Add in the plug in to be disabled. I enabled the plugin and it worked very well. Let us see that with images. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: PowerPivot

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  • Anatomy of a .NET Assembly - CLR metadata 2

    - by Simon Cooper
    Before we look any further at the CLR metadata, we need a quick diversion to understand how the metadata is actually stored. Encoding table information As an example, we'll have a look at a row in the TypeDef table. According to the spec, each TypeDef consists of the following: Flags specifying various properties of the class, including visibility. The name of the type. The namespace of the type. What type this type extends. The field list of this type. The method list of this type. How is all this data actually represented? Offset & RID encoding Most assemblies don't need to use a 4 byte value to specify heap offsets and RIDs everywhere, however we can't hard-code every offset and RID to be 2 bytes long as there could conceivably be more than 65535 items in a heap or more than 65535 fields or types defined in an assembly. So heap offsets and RIDs are only represented in the full 4 bytes if it is required; in the header information at the top of the #~ stream are 3 bits indicating if the #Strings, #GUID, or #Blob heaps use 2 or 4 bytes (the #US stream is not accessed from metadata), and the rowcount of each table. If the rowcount for a particular table is greater than 65535 then all RIDs referencing that table throughout the metadata use 4 bytes, else only 2 bytes are used. Coded tokens Not every field in a table row references a single predefined table. For example, in the TypeDef extends field, a type can extend another TypeDef (a type in the same assembly), a TypeRef (a type in a different assembly), or a TypeSpec (an instantiation of a generic type). A token would have to be used to let us specify the table along with the RID. Tokens are always 4 bytes long; again, this is rather wasteful of space. Cutting the RID down to 2 bytes would make each token 3 bytes long, which isn't really an optimum size for computers to read from memory or disk. However, every use of a token in the metadata tables can only point to a limited subset of the metadata tables. For the extends field, we only need to be able to specify one of 3 tables, which we can do using 2 bits: 0x0: TypeDef 0x1: TypeRef 0x2: TypeSpec We could therefore compress the 4-byte token that would otherwise be needed into a coded token of type TypeDefOrRef. For each type of coded token, the least significant bits encode the table the token points to, and the rest of the bits encode the RID within that table. We can work out whether each type of coded token needs 2 or 4 bytes to represent it by working out whether the maximum RID of every table that the coded token type can point to will fit in the space available. The space available for the RID depends on the type of coded token; a TypeOrMethodDef coded token only needs 1 bit to specify the table, leaving 15 bits available for the RID before a 4-byte representation is needed, whereas a HasCustomAttribute coded token can point to one of 18 different tables, and so needs 5 bits to specify the table, only leaving 11 bits for the RID before 4 bytes are needed to represent that coded token type. For example, a 2-byte TypeDefOrRef coded token with the value 0x0321 has the following bit pattern: 0 3 2 1 0000 0011 0010 0001 The first two bits specify the table - TypeRef; the other bits specify the RID. Because we've used the first two bits, we've got to shift everything along two bits: 000000 1100 1000 This gives us a RID of 0xc8. If any one of the TypeDef, TypeRef or TypeSpec tables had more than 16383 rows (2^14 - 1), then 4 bytes would need to be used to represent all TypeDefOrRef coded tokens throughout the metadata tables. Lists The third representation we need to consider is 1-to-many references; each TypeDef refers to a list of FieldDef and MethodDef belonging to that type. If we were to specify every FieldDef and MethodDef individually then each TypeDef would be very large and a variable size, which isn't ideal. There is a way of specifying a list of references without explicitly specifying every item; if we order the MethodDef and FieldDef tables by the owning type, then the field list and method list in a TypeDef only have to be a single RID pointing at the first FieldDef or MethodDef belonging to that type; the end of the list can be inferred by the field list and method list RIDs of the next row in the TypeDef table. Going back to the TypeDef If we have a look back at the definition of a TypeDef, we end up with the following reprensentation for each row: Flags - always 4 bytes Name - a #Strings heap offset. Namespace - a #Strings heap offset. Extends - a TypeDefOrRef coded token. FieldList - a single RID to the FieldDef table. MethodList - a single RID to the MethodDef table. So, depending on the number of entries in the heaps and tables within the assembly, the rows in the TypeDef table can be as small as 14 bytes, or as large as 24 bytes. Now we've had a look at how information is encoded within the metadata tables, in the next post we can see how they are arranged on disk.

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