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  • SQL to CodeIgniter Array Missing Data Issue

    - by SamD
    $query = $this->db->query("SELECT t1.numberofbets, t1.profit, t2.seven_profit, t3.28profit, user.user_id, username, password, email, balance, user.date_added, activation_code, activated FROM user LEFT JOIN (SELECT user_id, SUM(amount_won) AS profit, count(tip_id) AS numberofbets FROM tip GROUP BY user_id) as t1 ON user.user_id = t1.user_id LEFT JOIN (SELECT user_id, SUM(amount_won) AS seven_profit FROM tip WHERE date_settled > '$seven_daystime' GROUP BY user_id) as t2 ON user.user_id = t2.user_id LEFT JOIN (SELECT user_id, SUM(amount_won) AS 28profit FROM tip WHERE date_settled > '$twoeight_daystime' GROUP BY user_id) as t3 ON user.user_id = t3.user_id where activated = 1 GROUP BY user.user_id ORDER BY user.date_added DESC"); return $query->result_array(); The query works fine running it in phpMyAdmin and returns complete results (in image attached). However, printing the array in CodeIgniter, it has no value for one field ,seven_profit, where it is there in the SQL query ran in phpMyAdmin, just the discrepancy in this one field, from sql to php array... I just can’t see why, when printing the array, that one field, which should have value of 26, contains nothing? Any ideas? I changed the field name from starting with a number in attempt to fix it, but no difference. I know this is complex and looks horrible, any help or just people coming across something similar would be great to know about, thanks. Sam

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  • Ajax heavy JS apps using excessive amounts of memory over time.

    - by Shane Reustle
    I seem to have some pretty large memory leaks in an app that I am working on. The app itself is not very complex. Every 15 seconds, the page requests approx 40kb of JSON from the server, and draws a table on the page using it. It is cheaper to draw the table over because the data is usually always new. I am attaching a few events to the table, approx 5 per line, 30 lines in the table. I used jQuery's .html() method to put the new html into the container and overwrite the existing. I do this specifically so that jQuery's special cleanup functions go in and attempt to detach all events on the elements in the element that it is overwriting. I then also delete the large variables of html once they are sent to the DOM using delete my_var. I have checked for circular references and attached events that are never cleared a few times, but never REALLY dug into it. I was wondering if someone could give me a few pointers on how to optimize a very heavy app like this. I just picked up "High Performance Javascript" by Nicholas Zakas, but didn't have much time to get into it yet. To give an idea on how much memory this is using, after 4~ hours, it is using about 420,000k on chrome, and much more on Firefox or IE. Thanks!

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  • Yet another "What is this code doing"-type of Perl code

    - by Mike
    I have inherited some code from a guy whose favorite past time was to shorten every line to its absolute minimum (and sometimes only to make it look cool). His code is hard to understand but I managed to understand (and rewrite) most of it. Now I have stumbled on a piece of code which, no matter how hard I try, I cannot understand. my @heads = grep {s/\.txt$//} OSA::Fast::IO::Ls->ls($SysKey,'fo','osr/tiparlo',qr{^\d+\.txt$}) || (); my @selected_heads = (); for my $i (0..1) { $selected_heads[$i] = int rand scalar @heads; for my $j (0..@heads-1) { last if (!grep $j eq $_, @selected_heads[0..$i-1]); $selected_heads[$i] = ($selected_heads[$i] + 1) % @heads; #WTF? } my $head_nr = sprintf "%04d", $i; OSA::Fast::IO::Cp->cp($SysKey,'',"osr/tiparlo/$heads[$selected_heads[$i]].txt","$recdir/heads/$head_nr.txt"); OSA::Fast::IO::Cp->cp($SysKey,'',"osr/tiparlo/$heads[$selected_heads[$i]].cache","$recdir/heads/$head_nr.cache"); } From what I can understand, this is supposed to be some kind of randomizer, but I never saw a more complex way to achieve randomness. Or are my assumptions wrong? At least, that's what this code is supposed to do. Select 2 random files and copy them. === NOTES === The OSA Framework is a Framework of our own. They are named after their UNIX counterparts and do some basic testing so that the application does not need to bother with that.

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  • Should frontend and backend handled by different controllers?

    - by DR
    In my previous learning projects I always used a single controller, but know I wonder if that is good practice or even always possible. In all RESTful Rails tutorials the controllers have a show, an edit and an index view. If an authorized user is logged on, the edit view becomes available and the index view shows additional data manipulation controls, like a delete button or a link to the edit view. Now I have a Rails application which falls exactly into this pattern, but the index view is not reusable: The normal user sees a flashy index page with lots of pictures, complex layout, no Javascript requirement, ... The Admin user index has a completly different minimalistic design, jQuery table and lots of additional data, ... Now I'm not sure how to handle this case. I can think of the following: Single controller, single view: The view is split into two large blocks/partials using an if statement. Single controller, two views: index and index_admin. Two different controllers: BookController and BookAdminController None of this solutions seems perfect, but for now I'm inclined to use the 3rd option. What's the preferred way to do this?

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  • Making Javascript and HTML5 games

    - by Jeff Meatball Yang
    A long time ago (Netscape 4-era), I wrote Javascript-based games: Pong, Minesweeper, and John Conway's Life among them. I'm getting back into it, and want to get my hands even dirtier. I have a few games in mind: Axis & Allies clone, with rugged maps and complex rules. Tetris clone, possibly with real-time player-vs-player or player-vs-computer mode Breakout clone, with a couple weapons and particle velocities In all of these, I have only a few objectives: Use JavaScript and HTML 5 - it should run on Chrome, Safari, or maybe an iPad. Start small and simple, then build-up features. Learn something new about game design and implementation. So my questions are: How would you implement these games? Do you have any technology recommendations? If you've written these games, what was the hardest part? N.B. I also want to start from first-principles - if you recommend a framework/library, I would appreciate some theory or implementation details behind it. These games are different enough that I should learn something new from each one.

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  • Sharing storage between servers

    - by El Yobo
    I have a PHP based web application which is currently only using one webserver but will shortly be scaling up to another. In most regards this is pretty straightforward, but the application also stores a lot of files on the filesystem. It seems that there are many approaches to sharing the files between the two servers, from the very simple to the reasonably complex. These are the options that I'm aware of Simple network storage NFS SMB/CIFS Clustered filesystems Lustre GFS/GFS2 GlusterFS Hadoop DFS MogileFS What I want is for a file uploaded via one webserver be immediately available if accessed through the other. The data is extremely important and absolutely cannot be lost, so whatever is implemented needs to a) never lose data and b) have very high availability (as good as, or better, than a local filesystem). It seems like the clustered filesystems will also provide faster data access than local storage (for large files) but that isn't of vita importance at the moment. What would you recommend? Do you have any suggestions to add or anything specifically to look out for with the above options? Any suggestions on how to manage backup of data on the clustered filesystems?

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  • User preferences using SQL and JavaScript

    - by Shyam
    Hi, I am using Server Side JavaScript - yes, I am actually using Server Side JavaScript. To complexify things even more, I use Oracle as a backend database (10g). With some crazy XSLT and mutant-like HTML generation, I can build really fancy web forms - yes, I am aware of Rails and other likewise frameworks and I choose the path of horror instead. I have no JQuery or other fancy framework at my disposal, just plain ol' JavaScript that should be supported by the underlying engine called Mozilla Rhino. Yes, it is insane and I love it. So, I have a bunch of tables at my disposal and some of them are filled with associative keys that link to values. As I am a people pleaser, I want to add some nifty user-preference driven solutions. My users have all an unique user_id and this user_id is available during the entire session. My initial idea is to have a user preference table, where I have "three" columns: user_id, feature and pref_string. Using a delimiter, such as : or - (haven't thought about a suitable one yet), I could like store a bunch of preferences as a list and store its elements inside an array using the .split-method (similar like the PHP-explode function). The feature column could be like the table name or some identifier for the "feature" i want to link preferences too. I hate hardcoding objects, especially as I want to be able to back these up and reuse this functionality application-wide. Of course I would love better ideas, just keep in mind I cannot just add a library that easily. These preferences could be like "joined" to the table, so I can query it and use its values. I hope it doesn't sounds too complex, because well.. its basically something really simple I need. Thanks!

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  • why doesn't winmain set the errorlevel?

    - by Brian R. Bondy
    int APIENTRY _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { MessageBox(NULL, _T("This should return 90 no?"), _T("OK"), MB_OK); return 90; } Why does the above program correctly display the message box, but does not set the error level? I compile this program to the name a.exe. Then from command prompt I type: c:\> a.exe (message box is displayed, I press ok) c:\> echo %ERRORLEVEL% 0 I get the same results if I do exit(90); right before the return. It still says 0. I also tried to start the program via CreateProcess and obtain the result with GetExitCodeProcess but it also returns 0 to me. I did error checking to ensure it was all started correctly. I originally seen this problem in a more complex program. But made this simple program to verify the problem. Results are the same, both programs that have WinMain return 0 always. I tried both x64, x86 and unicode and MBCS compiling options. All give 0 as an error level/status code.

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  • How would the 'Model' in a Rails-type webapp be implemented in a functional programming langauge?

    - by ceptorial
    In MVC web development frameworks such as Ruby on Rails, Django, and CakePHP, HTTP requests are routed to controllers, which fetch objects which are usually persisted to a backend database store. These objects represent things like users, blog posts, etc., and often contain logic within their methods for permissions, fetching and/or mutating other objects, validation, etc. These frameworks are all very much object oriented. I've been reading up recently on functional programming and it seems to tout tremendous benefits such as testability, conciseness, modularity, etc. However most of the examples I've seen for functional programming implement trivial functionality like quicksort or the fibonnacci sequence, not complex webapps. I've looked at a few 'functional' web frameworks, and they all seem to implement the view and controller just fine, but largely skip over the whole 'model' and 'persistence' part. (I'm talking more about frameworks like Compojure which are supposed to be purely functional, versus something Lift which conveniently seems to use the OO part of Scala for the model -- but correct me if I'm wrong here.) I haven't seen a good explanation of how functional programming can be used to provide the metaphor that OO programming provides, i.e. tables map to objects, and objects can have methods which provide powerful, encapsulated logic such as permissioning and validation. Also the whole concept of using SQL queries to persist data seems to violate the whole 'side effects' concept. Could someone provide an explanation of how the 'model' layer would be implemented in a functionally programmed web framework?

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  • PHP/MySQL - Working with two databases, one shared and one local to an instance of application

    - by Extrakun
    The situation: Using a off-the-shelf PHP application, I have to add in a new module for extra functionality. Today, it is made known that eventually four different instances of the application are to be deployed, but the data from the new functionality is to be shared among those 4 instances. Each instance should still have their own database for users, content and etc. So the data for the new functionality goes into a 'shared' database. The data for the application (user login, content, uploads) go into a 'local' database To make things more complex, the new module I am writing will fetch data from the local DB and the shared DB at the same time. A re-write of the base application will take too long. I only have control over the new module which I am writing. The ideal solution: Is there a way to encapsulate 2 databases into one name using MySQL? I do not wish to switch DB connections or specifically name the DB to query from inside my SQL statements. The application uses a DB wrapper, so I am able to change it somehow so I can invisibly attempt to read/write to two different DB. What is the best way to handle this problem?

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  • Rhino Mocks Partial Mock

    - by dotnet crazy kid
    I am trying to test the logic from some existing classes. It is not possible to re-factor the classes at present as they are very complex and in production. What I want to do is create a mock object and test a method that internally calls another method that is very hard to mock. So I want to just set a behaviour for the secondary method call. But when I setup the behaviour for the method, the code of the method is invoked and fails. Am I missing something or is this just not possible to test without re-factoring the class? I have tried all the different mock types (Strick,Stub,Dynamic,Partial ect.) but they all end up calling the method when I try to set up the behaviour. using System; using MbUnit.Framework; using Rhino.Mocks; namespace MMBusinessObjects.Tests { [TestFixture] public class PartialMockExampleFixture { [Test] public void Simple_Partial_Mock_Test() { const string param = "anything"; //setup mocks MockRepository mocks = new MockRepository(); var mockTestClass = mocks.StrictMock<TestClass>(); //record beahviour *** actualy call into the real method stub *** Expect.Call(mockTestClass.MethodToMock(param)).Return(true); //never get to here mocks.ReplayAll(); //this is what i want to test Assert.IsTrue(mockTestClass.MethodIWantToTest(param)); } public class TestClass { public bool MethodToMock(string param) { //some logic that is very hard to mock throw new NotImplementedException(); } public bool MethodIWantToTest(string param) { //this method calls the if( MethodToMock(param) ) { //some logic i want to test } return true; } } } }

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  • De-normalization alternative to specific MYSQL problem?

    - by Booker
    I am facing quite a specific optimization problem. I currently have 4 normalized tables of data. Every second, possibly thousands of users will pull down up-to-date info from these tables using AJAX. The thing is that I can predict relatively easily which subset of data they need... The most recent 100 or so entries in those 4 normalized tables. I have been researching de-normalization... but feel that perhaps there is an easier solution. I was thinking that I could somehow every second run one sql query to condense the needed info, store it in a temp cached table and then have all of the user queries just draw from this. This will allow the complex join of 4 tables to only be run once, and then from there the users just need to do a simple lookup from the cached table. I really don't know if this is feasible. Comments on this or any other suggestions would be much appreciated. Thanks!

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  • Can you recommend a full-text search engine?

    - by Jen
    Can you recommend a full-text search engine? (Preferably open source) I have a database of many (though relatively short) HTML documents. I want users to be able to search this database by entering one or more search words in my C++ desktop application. Hence, I’m looking for a fast full-text search solution to integrate with my app. Ideally, it should: Skip common words, such as the, of, and, etc. Support stemming, i.e. search for run also finds documents containing runner, running and ran. Be able to update its index in the background as new documents are added to the database. Be able to provide search word suggestions (like Google Suggest) Have a well-documented API To illustrate, assume the database has just two documents: Document 1: This is a test of text search. Document 2: Testing is fun. The following words should be in the index: fun, search, test, testing, text. If the user types t in the search box, I want the application to be able to suggest test, testing and text (Ideally, the application should be able to query the search engine for the 10 most common search words starting with t). A search for testing should return both documents. Other points: I don't need multi-user support I don't need support for complex queries The database resides on the user's computer, so the indexing should be performed locally. Can you suggest a C or C++ based solution? (I’ve briefly reviewed CLucene and Xapian, but I’m not sure if either will address my needs, especially querying the search word indexes for the suggest feature).

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  • Creating nested arrays on the fly

    - by adardesign
    I am trying to do is to loop this HTML and get a nested array of this HTML values that i want to grab. It might look complex at first but is a simple question... This script is just part of a Object containing methods. html <div class="configureData"> <div title="Large"> <a href="yellow" title="true" rel="$55.00" name="sku22828"></a> <a href="green" title="true" rel="$55.00" name="sku224438"></a> <a href="Blue" title="true" rel="$55.00" name="sku22222"></a> </div> <div title="Medium"> <a href="yellow" title="true" rel="$55.00" name="sku22828"></a> <a href="green" title="true" rel="$55.00" name="sku224438"></a> <a href="Blue" title="true" rel="$55.00" name="sku22222"></a> </div> <div title="Small"> <a href="yellow" title="true" rel="$55.00" name="sku22828"></a> <a href="green" title="true" rel="$55.00" name="sku224438"></a> <a href="Blue" title="true" rel="$55.00" name="sku22222"></a> </div> </div> javascript // this is part of a script..... parseData:function(dH){ dH.find(".configureData div").each(function(indA, eleA){ colorNSize.tempSizeArray[indA] = [eleA.title,[],[],[],[]] $(eleZ).find("a").each(function(indB, eleB){ colorNSize.tempSizeArray[indA][indB+1] = eleC.title }) }) }, I expect the end array should look like this. [ ["large", ["yellow", "green", "blue"], ["true", "true", "true"], ["$55", "$55","$55"] ], ["Medium", ["yellow", "green", "blue"], ["true", "true", "true"], ["$55", "$55","$55"] ] ] // and so on....

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  • What is the cleanest way to use anonymous functions?

    - by Fletcher Moore
    I've started to use Javascript a lot more, and as a result I am writing things complex enough that organization is becoming a concern. However, this question applies to any language that allows you to nest functions. Essentially, when should you use an anonymous function over a named global or inner function? At first I thought it was the coolest feature ever, but I think I am going overboard. Here's an example I wrote recently, ommiting all the variable delcarations and conditionals so that you can see the structure. function printStream() { return fold(function (elem, acc) { ... var comments = (function () { return fold(function (comment, out) { ... return out + ...; }, '', elem.comments); return acc + ... + comments; }, '', data.stream); } I realized though (I think) there's some kind of beauty in being so compact, it is probably isn't a good idea to do this in the same way you wouldn't want a ton of code in a double for loop.

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  • Rolling back file moves, folder deletes and mysql queries

    - by Workoholic
    This has been bugging me all day and there is no end in sight. When the user of my php application adds a new update and something goes wrong, I need to be able to undo a complex batch of mixed commands. They can be mysql update and insert queries, file deletes and folder renaming and creations. I can track the status of all insert commands and undo them if an error is thrown. But how do I do this with the update statements? Is there a smart way (some design pattern?) to keep track of such changes both in the file structure and the database? My database tables are MyISAM. It would be easy to just convert everything to InnoDB, so that I can use transactions. That way I would only have to deal with the file and folder operations. Unfortunately, I cannot assume that all clients have InnoDB support. It would also require me to convert many tables in my database to InnoDB, which I am hesitant to do.

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  • How do tools like Hiphop for PHP deal with heterogenous arrays?

    - by Derek Thurn
    I think HipHop for PHP is an interesting tool. It essentially converts PHP code into C++ code. Cross compiling in this manner seems like a great idea, but I have to wonder, how do they overcome the fundamental differences between the two type systems? One specific example of my general question is heterogeneous data structures. Statically typed languages don't tend to let you put arbitrary types into an array or other container because they need to be able to figure out the types on the other end. If I have a PHP array like this: $mixedBag = array("cat", 42, 8.5, false); How can this be represented in C++ code? One option would be to use void pointers (or the superior version, boost::any), but then you need to cast when you take stuff back out of the array... and I'm not at all convinced that the type inferencer can always figure out what to cast to at the other end. A better option, perhaps, would be something more like a union (or boost::variant), but then you need to enumerate all possible types at compile time... maybe possible, but certainly messy since arrays can contain arbitrarily complex entities. Does anyone know how HipHop and similar tools which go from a dynamic typing discipline to a static discipline handle these types of problems?

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  • Getting a handle on GIS math, where do I start?

    - by Joshua
    I am in charge of a program that is used to create a set of nodes and paths for consumption by an autonomous ground vehicle. The program keeps track of the locations of all items in its map by indicating the item's position as being x meters north and y meters east of an origin point of 0,0. In the real world, the vehicle knows the location of the origin's lat and long, as it is determined by a dgps system and is accurate down to a couple centimeters. My program is ignorant of any lat long coordinates. It is one of my goals to modify the program to keep track of lat long coords of items in addition to an origin point and items' x,y position in relation to that origin. At first blush, it seems that I am going to modify the program to allow the lat long coords of the origin to be passed in, and after that I desire that the program will automatically calculate the lat long of every item currently in a map. From what I've researched so far, I believe that I will need to figure out the math behind converting to lat long coords from a UTM like projection where I specify the origin points and meridians etc as opposed to whatever is defined already for UTM. I've come to ask of you GIS programmers, am I on the right track? It seems to me like there is so much to wrap ones head around, and I'm not sure if the answer isn't something as simple as, "oh yea theres a conversion from meters to lat long, here" Currently, due to the nature of DGPS, the system really doesn't need to care about locations more than oh, what... 40 km? radius away from the origin. Given this, and the fact that I need to make sure that the error on my coordinates is not greater than .5 meters, do I need anything more complex than a simple lat/long to meters conversion constant? I'm knee deep in materials here. I could use some pointers about what concepts to research. Thanks much!

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  • How to use the same element name in different purposes ( in XML and DTD ) ?

    - by BugKiller
    Hi, I Want to create a DTD schema for this xml document: <root> <student> <name> <firstname>S1</firstname> <lastname>S2</lastname> </name> </student> <course> <name>CS101</name> </course> </root> as you can see , the element name in the course contains plain text ,but the element name in the student is complex type ( first-name, last-name ). The following is the DTD: <!ELEMENT root (course|student)*> <!ELEMENT student (name)> <!ELEMENT name (lastname|firstname)> <!ELEMENT firstname (#PCDATA)> <!ELEMENT lastname (#PCDATA)> <!ELEMENT course (name)> When I want to validate it , I get an error because the course's name has different structure then the student's name . My Question: how can I make a work-around solution for this situation without changing the name of element name using DTD not xml schema . Thanks.

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  • Windows 7 Aero Theme Progress Bar Bug?

    - by jmatthias
    I have ran into what I consider to be a progress bar bug on Windows 7. To demonstrate the bug I created a WinForm application with a button and a progress bar. In the button's 'on-click' handle I have the following code. private void buttonGo_Click(object sender, EventArgs e) { this.progressBar.Minimum = 0; this.progressBar.Maximum = 100; this.buttonGo.Text = "Busy"; this.buttonGo.Update(); for (int i = 0; i <= 100; ++i) { this.progressBar.Value = i; this.Update(); System.Threading.Thread.Sleep(10); } this.buttonGo.Text = "Ready"; } The expected behavior is for the progress bar to advance to 100% and then the button text to change to 'Ready'. However, when developing this code on Windows 7, I noticed that the progress bar would rise to about 75% and then the button text would change to 'Ready'. Assuming the code is synchronous, this should not happen! On further testing I found that the exact same code running on Windows Server 2003 produced the expected results. Furthermore, choosing a non aero theme on Windows 7 produces the expected results. In my mind, this seems like a bug. Often it is very hard to make a progress bar accurate when the long operation involves complex code but in my particular case it was very straight forward and so I was little disappointed when I found the progress control did not accurately represent the progress. Has anybody else noticed this behavior? Has anybody found a workaround?

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  • C Run-Time library part 2

    - by b-gen-jack-o-neill
    Hi, I was suggested when I have some further questions on my older ones, to create newer Question and reffer to old one. So, this is the original question: What is the C runtime library? OK, from your answers, I now get thet statically linked libraries are Microsoft implementation of C standart functions. Now: If I get it right, the scheme would be as follow: I want to use printf(), so I must include which just tels compiler there us functio printf() with these parameters. Now, when I compile code, becouse printf() is defined in C Standart Library, and becouse Microsoft decided to name it C Run Time library, it gets automatically statically linked from libcmt.lib (if libcmt.lib is set in compiler) at compile time. I ask, becouse on wikipedia, in article about runtime library there is that runtime library is linked in runtime, but .lib files are linked at compile time, am I right? Now, what confuses me. There is .dll version of C standart library. But I thought that to link .dll file, you must actually call winapi program to load that library. So, how can be these functions dynamically linked, if there is no static library to provide code to tell Windows to load desired functions from dll? And really last question on this subject - are C Standart library functions also calls to winapi even they are not .dll files like more advanced WinAPI functions? I mean, in the end to access framebuffer and print something you must tell Windows to do it, since OS cannot let you directly manipulate HW. I think of it like the OS must be written to support all C standart library functions same way across similiar versions, since they are statically linked, and can differently support more complex WinAPI calls becouse new version of OS can have adjustements in the .dll file.

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  • jQuery Accordion

    - by Fuego DeBassi
    Just wondering if anyone can provide some basic advice on an accordion I'm trying to simplify. Got a working version, but it seems way overly complex. Here is my new JS. $(document).ready(function() { $("#themes li ul").hide(); $("#themes li").hover(function() { $("ul").show(); }, function() { $("li ul").hide(); }); The markup looks like this: <ul> <li>Tier 1 <ul> <li>Tier 2</li> <li>Tier 2</li> </ul> </li> <li>Tier 1 <ul> <li>Tier 2</li> <li>Tier 2</li> </ul> </li> </ul> My script works alright. But it shows all of the child ul's when any parent li is hovered, and it hides all the child ul's when unhovered. Just not sure how I can get it to A.) Only .show the li ul when that specific li is hovered. And B.) Hide the shown li ul only when another one is hovered (not itself). Example + explanation would be especially helpful! Thanks!!

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  • Validating collection elements in WPF

    - by Chris
    I would like to know how people are going about validating collections in WPF. Lets say for example that I have an observable collection of ViewModels that I am binding to the items source of a grid, and the user can add new rows to the grid and needs to fill them. First of all I need to validate on each row to ensure that required fields of each ViewModel are filled in. This is fine and simple to do for each row. However, the second level of validation is on the collection as a whole. For example i want to ensure that no two rows of the collection have the same identifier, or that no two rows have the same name. Im basically checking for duplicate properties within different rows. I also have more complex conditions where I must ensure that there is at least one item within the collection that has some property set. How do I get a validation rule that would allow me to check these rules, validating on the whole collection rather than the individual items. I also want to print any validation error above the datagrid so that the user can fix the problem and the message will update or disappear as the user fixes each different rule. Anyone have any experience of the proper way to do this? Thanks Chris

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  • Advantage Database Server ORDER BY behaviour

    - by ie
    I'm using ADS v10 beta. I'm trying to numerate ordered resultset. 1) ORDER BY in nested queries. I need to use nested SELECT for some calculations: SELECT Name, Value, ROWNUM() FROM (SELECT * FROM MainTable WHERE Value > 0 ORDER BY Value) a And I'm getting Expected lexical element not found: ) There was a problem parsing the table names after the FROM keyword in your SELECT statement. Everything is working well when the ORDER BY is removed. Although, I found the sample in the Help, it looks like my query (more complex, indeed): SELECT * FROM (SELECT TOP 10 empid, fullname FROM branch1 ORDER BY empid) a UNION SELECT empid, fullname FROM branch2 ORDER BY empid 2) ORDER BY + ROWNUM(). I used the nested query in the example above, to numerate ordered rows. Is there are any chance to avoid nested query? In the SQL Server I can do something like this: SELECT Name, Value, ROW_NUMBER() OVER(ORDER BY Value) FROM MainTable WHERE Value > 1 ORDER BY Value Please advice. Thanks.

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  • How to get to the key name of a referenced entity property from an entity instance without a datastore read in google app engine?

    - by Sumeet Pareek
    Consider I have the following models - class Team(db.Model): # say I have just 5 teams name = db.StringProperty() class Player(db.Model): # say I have thousands of players name = db.StringProperty() team = db.ReferenceProperty(Team, collection_name="player_set") Key name for each Team entity = 'team_' , and for each Player entity = 'player_' By some prior arrangement I have a Team entity's (key_name, name) mapping available to me. For example (team_01, United States Of America), (team_02, Russia) etc I have to show all the players and their teams on a page. One way of doing this would be - players = Player.all().fetch(1000) # This is 1 DB read for player in players: # This will iterate 1000 times self.response.out.write(player.name) # This is obviously not a DB read self.response.out.write(player.team.name) #This is a total of 1x1000 = 1000 DB reads That is a 1001 DB reads for a silly thing. The interesting part is that when I do a db.to_dict() on players, it shows that for every player in that list there is 'name' of the player and there is the 'key_name' of the team available too. So how can I do the below ?? players = Player.all().fetch(1000) # This is 1 DB read for player in players: # This will iterate 1000 times self.response.out.write(player.name) # This is obviously not a DB read self.response.out.write(team_list[player.<SOME WAY OF GETTING TEAM KEY NAME>]) # Here 'team_list' already has (key_name, name) for all 5 teams I have been struggling with this for a long time. Have read every available documentation. I could just hug the person that can help me here :-) Disclaimer: The above problem description is not a real scenario. It is a simplified arrangement that represents my problem exactly. I have run into it in a rater complex and big GAE appication.

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