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• Maintaining sort order of database table rows

  - by Lox

  Say I have at database table containing information about a news article in each row. The table has an integer "sort" column to dictate the order in which the articles are to be presented on a web site. How do I best implement and maintain this sort order. The problem I want to avoid is having the the articles numbered 1,2,3,4,..,100 and when article number 50 suddenly becomes interesting it gets its sort number set to 1 and then all articles between them must have their sort number increased by one. Sure, setting initial sort numbers to 100,200,300,400 etc. leaves some space for moving around but at some point it will break. Is there a correct way to do this, maybe a completely different approach? Added-1: All article titles are shown in a list linking to the contents, so yes all sorted items are show at once. Added-2: An item is not necessarily moved to the top of the list; any item can be placed anywhere in the ordered list.

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• How do I use dependencies in a makefile without calling a target?

  - by rassie

  I'm using makefiles to convert an internal file format to an XML file which is sent to other colleagues. They would make changes to the XML file and send it back to us (Don't ask, this needs to be this way ;)). I'd like to use my makefile to update the internal files when this XML changes. So I have these rules: %.internal: $(DATAFILES) # Read changes from XML if any # Create internal representation here %.xml: %.internal # Convert to XML here Now the XML could change because of the workflow described above. But since no data files have changed, make would tell me that file.internal is up-to-date. I would like to avoid making %.internal target phony and a circular dependency on %.xml obviously doesn't work. Any other way I could force make to check for changes in the XML file and re-build %.internal?

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• What could be adding "Pragma:no-cache" to my response Headers? (Apache, PHP)

  - by Daniel Magliola

  I have a website whose maintenance I've inherited, which is a big hairy mess. One of the things i'm doing is improving performance. Among other things, I'm adding Expires headers to images. Now, there are some images that are served through a PHP file, and I notice that they do have the Expires header, but they also get loaded every time. Looking at Response Headers, I see this: Expires Wed, 15 Jun 2011 18:11:55 GMT Cache-Control no-store, no-cache, must-revalidate, post-check=0, pre-check=0 Pragma no-cache Which obviously explains the problem. Now, i've looked all over the code base, and it doesn't say "pragma" anywhere. .htaccess doesn't seem to have anything related either. Any ideas who could be setting those "pragma" (and "cache-control") headers, and how I can avoid it? Thanks! Daniel

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• Controlling LaTeX column flow

  - by hdhermans

  What I'm trying to do: I have a page that consists of pairs of two sentences each. The pairs are separated by a whole line break. My problem is that when I have an odd number of pairs, the second sentence will automatically be placed on the next column. How can I use LaTeX to make block structures that multicol does not ignore, to keep the two sentences together? If there's better code to solve this problem, or a better column implementation (though I don't believe I can use \twocolumn in the document declaration), please post it. My current code: \documentclass{article} \usepackage{fullpage} \usepackage{multicol} \setlength{\parindent}{0pt} \setlength{\parskip}{\baselineskip} \newcommand{\pair}[2]{ \emph{#1}\\* #2 } \begin{document} \begin{multicols}{2} \pair{Sentence 1.}{Sentence 2.} \pair{Sentence 2 (pair 2).}{Sentence 2 (pair 2).} \pair{The last pair, first sentence.}{Last sentence.} \end{multicols} \end{document} This generates: http://img541.imageshack.us/img541/3444/columns.png . The second pair is what I am trying to avoid.

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• Getting the location in Android programatically

  - by steveo225

  I know this has been asked a ton, so my apologies. I have the following code, and cannot get the location, always a null response. I am trying to avoid a LocationListener in this instance because I am already using an update Service, and the location really doesn't have to be that fine, so the last known location is good enough. Thanks for the help. LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE); String providers[] = {"gps", "network", "passive"}; Location loc = null; for(String x : providers) { loc = lm.getLastKnownLocation(x); if(loc != null) break; } if(loc != null) { // do something, never reached }

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• How do you resolve the common naming collision between type and object?

  - by Catskul

  Since the standard c# convention is to capitalize the first letter of public properties, the old c++ convention of initial capital for type names, and initial lowercase for non-type names does not prevent the classic name collision where the most obvious object name matches the type name: class FooManager { public BarManager BarManager { get; set; } // Feels very wrong. // Recommended naming convention? public int DoIt() { // 1st and 2nd Bar Manager are different symbols return BarManager.Blarb + BarManager.StaticBlarb; } } class BarManager { public int Blarb { get; set; } public static int StaticBlarb { get; set; } } It seems to compile, but feels so wrong. Is there a recommend naming convention to avoid this?

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• Scoping in embedded groovy scripts

  - by Aaron Digulla

  In my app, I use Groovy as a scripting language. To make things easier for my customers, I have a global scope where I define helper classes and constants. Currently, I need to run the script (which builds the global scope) every time a user script is executed: context = setupGroovy(); runScript( context, "global.groovy" ); // Can I avoid doing this step every time? runScript( context, "user.groovy" ); Is there a way to setup this global scope once and just tell the embedded script interpreter: "Look here if you can't find a variable"? That way, I could run the global script once. Note: Security is not an issue here but if you know a way to make sure the user can't modify the global scope, that's an additional plus.

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• Client-side session timeout redirect in ASP.Net

  - by Mercury821

  I want to build a way to automatically redirect users to Timeout.aspx when their session expires due to inactivity. My application uses forms authentication and relies heavily on update panels within the same aspx page for user interaction, so I don't want to simply redirect after a page-level timer expires. For the same reason, I can't use '<meta http-equiv="refresh"/>' What I want to do is create a simple ajax web service with a method called IsSessionTimedOut(), that simply returns a boolean. I will use a javascript timer to periodically call the method, and if it returns true, then redirect to Timeout.aspx. However, I don't want calling this method to reset the session timeout timer, or the session would never time out because of the service call. Is there a clean way to avoid this catch-22? Hopefully there is an easy solution that has so far eluded me.

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• Fast parsing of PHP in C#

  - by Jessica Shea

  Hello there, I've got a requirement for parsing PHP files in C#. We essentially require some of the devs in another country to upload PHP files and once uploaded we need to check the php files and get a list of all the methods and classes/functions etc. I thought of using a regex but I can't workout if a function belongs to a class etc, so I was wondering if theres already something 'out there' that will parse out PHP files and spit out its functions (I'm trying to avoid writing a full blow AST implementation). Does anyone have any idea? I looked at Coco/R but I couldn't find a PHP grammar file. I'm using .NET 2.0 and C#.

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• Exception "Illegal attempt to associate a collection with two open sessions" when saving object

  - by Alex

  I am using CastleProject ActiveRecord and I use lazy load feature of this ORM. In order to make lazy load work, it is required to create SessionScope. I do this in Program.cs: public static SessionScope sessionScope; private static void InitializeActiveRecord() { ActiveRecordStarter.Initialize(); sessionScope = new SessionScope(); } This works fine for loading, however, when I try to save my objects, I get an exception saying "Illegal attempt to associate a collection with two open sessions". I guess this is due to the fact that I created one session myself. How to avoid this exception?

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• Performance of Managed C++ Vs UnManaged/native C++

  - by bsobaid

  I am writing a very high performance application that handles and processes hundreds of events every millisecond. Is Unmanaged C++ faster than managed c++? and why? Managed C++ deals with CLR instead of OS and CLR takes care of memory management, which simplifies the code and is probably also more efficient than code written by "a programmer" in unmanaged C++? or there is some other reason? When using managed, how can one then avoid dynamic memory allocation, which causes a performance hit, if it is all transparent to the programmer and handled by CLR? So coming back to my question, Is managed C++ more efficient in terms of speed than unmanaged C++ and why?

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• How to stop GHC from generating intermediate files?

  - by unknown

  When compiling a haskell source file via ghc --make foo.hs GHC always leaves behind a variety of intermediate files other than foo.exe. These are foo.hi and foo.o. I often end up having to delete the .hi and .o files to avoid cluttering up the folders. Is there a command line option for GHC not to leave behind its intermediate files? (When asked on #haskell, the best answer I got was ghc --make foo.hs && rm foo.hi foo.o.

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• XPath filter not empty attribute

  - by Marcos Buarque

  Hi, I need to filter a XPath expression to grab only a certain attribute as not empty. I tried this: <xsl:template match="DocumentElement/QueryResults[string(@FileName)]"> and this: <xsl:template match="DocumentElement/QueryResults[string-length(@FileName)>0]"> but it did not work. I need the same kind of data returning from the folloing XPath expression... <xsl:template match="DocumentElement/QueryResults"> ... but filtered to avoid items with empty attribute @FileName. Thanks!

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• Changing ylim (axis limits) drops data falling outside range. How can this be prevented?

  - by Alex Holcombe

  df <- data.frame(age=c(10,10,20,20,25,25,25),veg=c(0,1,0,1,1,0,1)) g=ggplot(data=df,aes(x=age,y=veg)) g=g+stat_summary(fun.y=mean,geom="point") Points reflect mean of veg at each age, which is what I expected and want to preserve after changing axis limits with the command below. g=g+ylim(0.2,1) Changing axis limits with the above command unfortunately causes veg==0 subset to be dropped from the data, yielding "Warning message: Removed 4 rows containing missing values (stat_summary)" This is bad because now the data plot (stat_summary mean) omits the veg==0 points. How can this be prevented? I simply want to avoid showing the empty part of the plot- the ordinate from 0 to .2, but not drop the associated data from the stat_summary calculation.

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• Using Report (Reporting Services) parameter values in ASP.NET page

  - by noup

  I have a report (Reporting Services) integrated into an ASP.NET that shows dropdownlists to select report parameter values. The dropdownlists are populated using direct database selects, though I see the report RDL files do contain the paramter values and datasets as defined in the report designer. Is it possible to obtain the report parameters "available values" in ASP.NET to populate the dropdownlists? This would avoid some code duplication. Update If the parameter doesn't use a query for available values, the following works: foreach (ValidValue value in this.ReportViewerControl.ServerReport.GetParameters()["myParameter"].ValidValues) { this.DropDownListControl.Items.Add(new ListItem(value.Label, value.Value)); } Still haven't found a way to access report datasets though...

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• In Python, how to use a C++ function which returns an allocated array of structs via a ** parameter?

  - by Jon-Eric

  I'd like to use some existing C++ code, NvTriStrip, in a Python tool. SWIG easily handles the functions with simple parameters, but the main function, GenerateStrips, is much more complicated. What do I need to put in the SWIG interface file to indicate that primGroups is really an output parameter and that it must be cleaned up with delete[]? /////////////////////////////////////////////////////////////////////////// // GenerateStrips() // // in_indices: input index list, the indices you would use to render // in_numIndices: number of entries in in_indices // primGroups: array of optimized/stripified PrimitiveGroups // numGroups: number of groups returned // // Be sure to call delete[] on the returned primGroups to avoid leaking mem // bool GenerateStrips( const unsigned short* in_indices, const unsigned int in_numIndices, PrimitiveGroup** primGroups, unsigned short* numGroups, bool validateEnabled = false ); FYI, here is the PrimitiveGroup declaration: enum PrimType { PT_LIST, PT_STRIP, PT_FAN }; struct PrimitiveGroup { PrimType type; unsigned int numIndices; unsigned short* indices; PrimitiveGroup() : type(PT_STRIP), numIndices(0), indices(NULL) {} ~PrimitiveGroup() { if(indices) delete[] indices; indices = NULL; } };

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• Store return value of function in reference C++

  - by Ruud v A

  Is it valid to store the return value of an object in a reference? class A { ... }; A myFunction() { A myObject; return A; } //myObject goes out of scope here void mySecondFunction() { A& mySecondObject = myFunction(); } Is it possible to do this in order to avoid copying myObject to mySecondObject? myObject is not needed anymore and should be exactly the same as mySecondObject so it would in theory be faster just to pass ownership of the object from one object to another. (This is also possible using boost shared pointer but that has the overhead of the shared pointer.) Thanks in advance.

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• Could not see memory being released on closing MFC modal dialog that hosts wpf user control using HW

  - by Naveen Chiluka

  This is in continuation with my last question posted "Continuous Memory leak while using WpfHWndSource" I have to load an WPF User Control in an MFC Modal Dialog that is being invoked from the ocx control. For this I have created a MFC Regular Dll(Mixed Mode Regular dll with clr option enabled), I have created a modal dialog which will host wpf user control using HWndSource. This exported dialog is placed as a child Dialog of the above MFC dialog that is being invoked from the ocx. Ny intermediate dialog uses C++/Cli code. When the main MFC dialog is closed, I am deleteing the ptr reference of the intermediate dialog created on the heap. In the the dipose of the .Net User Control, I have set most of the references that I have created to null, unsubscribed to the events (to avoid weak refernces), unbinded from the propertes(by using clear binding). Called delete on the HwndSource and the user control(which basically calls the dispose method). But I do not see complete memory being released. Any help would be greatful.

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• sqlplus remove \r \n \t from spool

  - by Tom

  Hi all, Is there any sql*plus command to remove \r \n and\t from the result set that's going out to the spool file? That is, "trim" every record? We've used set trim on in the past, but it doesn't seem to bue what we need right now. I'm trying to avoid calling oracle's translate, chr functions in the sql query. For example, If my query returns this |DATA| |\n \t\t\t\t\t thisistheactualdata \t\t\t\t\t\t\n| I'd like to keep this |DATA| |thisistheactualdata| Thanks in advance.

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• C sharp: read last "n" lines of log file

  - by frictionlesspulley

  need a snippet of code which would read out last "n lines" of a log file. I came up with the following code from the net.I am kinda new to C sharp. Since the log file might be quite large, I want to avoid overhead of reading the entire file.Can someone suggest any performance enhancement. I do not really want to read each character and change position. var reader = new StreamReader(filePath, Encoding.ASCII); reader.BaseStream.Seek(0, SeekOrigin.End); var count = 0; while (count <= tailCount) { if (reader.BaseStream.Position <= 0) break; reader.BaseStream.Position--; int c = reader.Read(); if (reader.BaseStream.Position <= 0) break; reader.BaseStream.Position--; if (c == '\n') { ++count; } } var str = reader.ReadToEnd();

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• Creating a Java platform game as easily as possible

  - by directx

  I need to create a Java-based platformer game for a high school project (not computer science related), and I want to spend as little time on technical stuff as possible. I'm already experienced in Java, and I already have most of the gameplay, graphics, etc. All I need to do is code it. I've looked and I'm considering one of two options that do not involving coding a game from scratch: Copy an existing Java platformer (best option, but I can't find an open source Java platformer) Use a Java game engine to avoid coding from scratch. I've looked at JGame but I'm not sure if it's the best bet for a platformer.

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• Why is there so much poorly indented code out there?

  - by dsimcha

  The more I browse the code to open source projects in languages that aren't Python, the more I realize that it seems a lot of programmers don't believe in proper indentation. (I won't mention any projects specifically to avoid having anyone take this question too personally.) Usually code is indented, but in a way just different enough from the standard style that it drives me crazy, especially in old/crufty code. I've noticed that when I write in C-like languages, I tend to indent correctly as religiously as when I'm writing in Python, with the exception of debugging code that I actually want to stick out like a sore thumb. Given how easy it is with a modern IDE to fix incorrect indentation, what are some rationales for not religiously keeping indentation in sync with braces?

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• JNDI Issues: Jboss 4.2.2 Spring 2.5 and hibernate ejb

  - by jon077

  I have a strange problem, that is causing me some grief. If the following jar is in my classpath: <dependency> <groupId>org.hibernate</groupId> <artifactId>org.hibernate.ejb</artifactId> <version>3.3.2.GA</version> </dependency> My JNDI lookup for my datasource returns null. Here is the basic code I am using to do the lookup: InitialDirContext ctx = new InitialDirContext(env); DataSource dataSource = (DataSource)ctx.lookup("java:dataContent"); Otherwise, the DataSource returns fine from the context. Unfortunately, I need the jar in order to avoid ClassCastExceptions within Jboss 4.2.2. Any help is appreciated.

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• "Error opening associated documents" message when loading VS

  - by kumar

  When loading up a solution in VS2008 I get this message: An error was encountered while opening associated documents the last time this solution was loaded. Document load is being skipped during this solution load in order to avoid that error. It shut down immediately the first time I opened it. The next time I opened it, VS popped up a message box but did not shut down at first; however, it did shut down when I clicked a usercontrol or ASPX page. How can I find which document is causing the problem? Thanks...

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• Retain cycle on `self` with blocks

  - by Jonathan Sterling

  I'm afraid this question is pretty basic, but I think it's relevant to a lot of Objective-C programmers who are getting into blocks. What I've heard is that since blocks capture local variables referenced within them as const copies, using self within a block can result in a retain cycle, should that block be copied. So, we are supposed to use __block to force the block to deal directly with self instead of having it copied. __block typeof(self) bself = self; [someObject messageWithBlock:^{ [bself doSomething]; }]; instead of just [someObject messageWithBlock:^{ [self doSomething]; }]; What I'd like to know is the following: if this is true, is there a way that I can avoid the ugliness (aside from using GC)?

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