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• oracle call stored procedure inside select

  - by CC

  Hi everybody. I'm working on a query (a SELECT) and I need to insert the result of this one in a table. Before doing the insert I have some checking to do, and if all columns are valid, I will do the insert. The checking is done in a stored procedure. The same procedure is used somewhere else too. So I'm thinking using the same procedure to do my checks. The procedure does the checkings and insert the values is all OK. I tryied to call the procedure inside my SELECT but it does not works. SELECT field1, field2, myproc(field1, field2) from MYTABLE. This kind of code does not works. I think it can be done using a cursor, but I would like to avoid the cursors. I'm looking for the easiest solution. Anybody, any idea ? Thanks alot. C.C.

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• Select n+1 problem

  - by Arnis L.

  Foo has Title. Bar references Foo. I have a collection with Bars. I need a collection with Foo.Title. If i have 10 bars in collection, i'll call db 10 times. bars.Select(x=x.Foo.Title) At the moment this (using NHibernate Linq and i don't want to drop it) retrieves Bar collection. var q = from b in Session.Linq<Bar>() where ... select b; I read what Ayende says about this. Another related question. A bit of documentation. And another related blog post. Maybe this can help? What about this? Maybe MultiQuery is what i need? :/ But i still can't 'compile' this in proper solution. How to avoid select n+1?

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• Caching result of SELECT statement for reuse in multiple queries

  - by Andrew

  I have a reasonably complex query to extract the Id field of the results I am interested in based on parameters entered by the user. After extracting the relevant Ids I am using the resulting set of Ids several times, in separate queries, to extract the actual output record sets I want (by joining to other tables, using aggregate functions, etc). I would like to avoid running the initial query separately for every set of results I want to return. I imagine my situation is a common pattern so I am interested in what the best approach is. The database is in MS SQL Server and I am using .NET 3.5.

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• Proper use of of typedef in C++

  - by dicroce

  I have coworkers who occasionally use typedef to avoid typing. For example: typedef std::list<Foobar> FoobarList; ... FoobarList GetFoobars(); Personally, I always hate coming across code like this, largely because it forces me to go lookup the typedef so I can tell how to use it. I also feel like this sort of thing is a potential slippery slope... If you do this, why aren't you doing it more? (pretty soon, your code is totally obfuscated). I found this SO question regarding this issue: when should I use typedef in C I have two questions: 1) am I truly alone in disliking this? 2) If the vast majority of people think this sort of typedef use is OK, what criteria do you use to determine whether to typedef a type?

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• Is there an easier way to reconcile a list of files and a directory with subfolders/files to find ch

  - by rwmnau

  I have a SQL Server table with a list of files (path + filename), and a folder with multiple layers and files in each layer. I'm looking for a way to reconcile the two without having to process the list twice. Currently, I'm doing this: For Each f as FileInfo In FileListFromDatabase If f.Exists is False, mark it as deleted in the database Next For Each f as FileInfo In RecursiveListOFFilesOnDisk If Not FileExistsInDatabase, then add it Next Is there a better way to do this? I'd like to avoid converting all the matching files (of which most will be) to FileInfo objects twice. Since I'm a T-SQL developer first, I'm picturing something like an OUTER JOIN of the two lists where they don't match. Something LINQ-ish?

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• Dynamic columns in C# rdlc report

  - by Mugume David

  Suppose I have a report that lists employees (as rows) with their respective taxes charged (in columns). It is possible for a new tax to come up. Since my rdlc report file is currently designed (from XML of-course) to statically generate the coulumns. A future shift in events will need me to alter the rdlc file and add in a new column. how can i do this dynamically. I intend to avoid opening the rdlc file and adding XML code.

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• Use a function in a conditions hash

  - by Pierre

  Hi, I'm building a conditions hash to run a query but I'm having a problem with one specific case: conditions2 = ['extract(year from signature_date) = ?', params[:year].to_i] unless params[:year].blank? conditions[:country_id] = COUNTRIES.select{|c| c.geography_id == params[:geographies]} unless params[:geographies].blank? conditions[:category_id] = CATEGORY_CHILDREN[params[:categories].to_i] unless params[:categories].blank? conditions[:country_id] = params[:countries] unless params[:countries].blank? conditions['extract(year from signature_date)'] = params[:year].to_i unless params[:year].blank? But the last line breaks everything, as it gets interpreted as follows: AND ("negotiations"."extract(year from signature_date)" = 2010 Is there a way to avoid that "negotiations"." is prepended to my condition? thank you, P.

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• How do I change the Unit:Characters in Matlab?

  - by Jonas

  For portability, I set the units of my GUIs to 'characters'. Now I have a user who wants to use Matlab on his netbook, and the GUI window is larger than the screen (and thus cropped at the top). I think I could try and write something in the openingFcn of the GUI that measures screen size and then adjusts the GUI accordingly, but I'd rather avoid that, because I then need to deal with text that is bigger than the text boxes, etc. What I'd rather like to do is somehow adjust the unit 'character' on his Matlab installation. None of the font sizes in the preferences seem to have an effect on unit:character, though. Does anyone know whether there's a setting for that, which can be changed from within Matlab (I don't mind if it's something that is reset at every reboot, since I can just put it into the startup script)?

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• PHP => Alternative to session data?

  - by Armz

  i have a Web Application where Cookies and Session are both important. Since the Web Application is load balanced on different server, i am looking for suggestions to Alternative Store for the Session data that all server will be able to access. Some sessions could live up to severals days. The solutions that come to my mind: - Native PHP Sessions (this is the one i want to stop using) - MySQL Database - Serialize and write to a file (i want to avoid this, for performances) - Memcache (however it could become very big or older data getting knocked out) Thanks in advance!

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• How to access device settings on a S60 symbian based mobile phone?

  - by TheRHCP

  Hello everyone, I recently bought a Sony Ericsson mobile phone which embeds Symbian S60 and I would like to add a missing feature myself. In fact I cannot actually disable Internet connection in an easy way when roaming, which cost me a lot of money last time I moved away ... So I would like to develop a little application that would just replace the actual Internet configuration with a fake configuration to avoid auto-connections. So what I would like to know is how can I access programmatically to my phone settings? I believe that this is possible but I do not really have a clue where to start. I know that Sony Ericsson provides a SDK to run Java applications on its customised JVM but Symbian is also providing a SDK to develop applications for S60 devices in many languages. The real questions is which SDK will provide an API able to access phone settings. This is not well documented so I am asking this question with the hope that someone here already had experience with development for Sony Ericsson/Symbian devices. Thanks.

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• Makefile rule depending on change of number of files instead of change in content of files.

  - by goathens

  I'm using a makefile to automate some document generation. I have several documents in a directory, and one of my makefile rules will generate an index page of those files. The list of files itself is loaded on the fly using list := $(shell ls documents/*.txt) so I don't have to bother manually editing the makefile every time I add a document. Naturally, I want the index-generation rule to trigger when number/title of files in the documents directory changes, but I don't know how to set up the prerequisites to work in this way. I could use .PHONY or something similar to force the index-generation to run all the time, but I'd rather not waste the cycles. I tried piping ls to a file list.txt and using that as a prerequisite for my index-generation rule, but that would require either editing list.txt manually (trying to avoid it), or auto-generating it in the makefile (this changes the creation time, so I can't use list.txt in the prerequisite because it would trigger the rule every time).

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• How do I ensure my abstract class's function can only operate on extenders of the same type as the c

  - by incrediman

  For example, let's say this is my abstract class: abstract class A{ int x; int y; void foo(A fooMe); } ...and B and C are two classes which extend A. What I want is for B to only be able to call foo() on other Bs, and for C to only be able to call foo() on other Cs. But I want this to be out of the hands of the programmer who's extending my A class - that is, I want a way to ensure this functionality within As code alone. What can I do? (If possible) I'd like to avoid any hack or generics solution that's too messy - I still want foo to be able to be called like this, for example: B b=new B(); B bb=new B(); bb.foo(b);

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• How do I delete an object from an Entity Framework model without first loading it?

  - by Tomas Lycken

  I am quite sure I've seen the answer to this question somewhere, but as I couldn't find it with a couple of searches on SO or google, I ask it again anyway... In Entity Framework, the only way to delete a data object seems to be MyEntityModel ent = new MyEntityModel(); ent.DeleteObject(theObjectToDelete); ent.SaveChanges(); However, this approach requires the object to be loaded to, in this case, the Controller first, just to delete it. Is there a way to delete a business object referencing only for instance its ID? If there is a smarter way using Linq or Lambda expressions, that is fine too. The main objective, though, is to avoid loading data just to delete it.

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• Replace html tag with a certain class

  - by fire

  I am looking for suitable replacement code that allows me replace the content inside of any HTML tag that has a certain class e.g. $class = "blah"; $content = "new content"; $html = '<div class="blah">hello world</div>'; // code to replace, $html now looks like: // <div class="blah">new content</div> Bare in mind that: It wont necessarily be a div, it could be <h2 class="blah"> The class can have more than one class and still needs to be replaced e.g. <div class="foo blah green">hello world</div> I am thinking regular expressions should be able to do this, if not I am open to other suggestions such as using the DOM class (although I would rather avoid this if possible because it has to be PHP4 compatible).

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• NHibernate SchemaUpdate adding existing foreign keys again?

  - by afsharm

  I'm using SchemaUpdate to synchronize my hbms with existing database. Database has recently created based on hbms and is completely up-to-date. But SchemaUpdate generates all foreign key constraints again. For example suppose you have Student and Teacher. Student has association to Teacher with name ArtTeacher. ArtTeacher is a foreign key from Student to Teacher. Suppose database is up-to-date and currently holde Student, Teacher and their foreign key relation. So HBM and Database are equivalent. Know SchemaUpdate must not do anything but when I see its generated scripts, it re-produce that foreign key again. Why this happens? Is there any way to avoid it?

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• How compiling circular dependencies works?

  - by Fabio F.

  I've made the example in Java but I think (not tested) that it works in other (all?) languages. You have 2 files M.java that says public class MType{ XType x; MType(){ x = null;} } and another file XType.java (in the same directory) public class XType{ MType m; public XType(MType m){ this.m=m;} } Ok it's BAD programming , but.. if you run javac XType it compiles: compiles even MTypes because XType needs it. But.. MType needs XType.. how it works? How does the compiler know what is happening? Probably is a stupid question, but I would like to know how the compiler (javac or other compilers if you know.) manages that situation, not how to avoid it. I'm asking because i'm writing a precompiler and I would like to manage that situation.. Thank you

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• What non-standard behaviour features does Gmail exhibit, when it is programmatically used as a POP3 server?

  - by Mike Green

  I am trying to prepare a complete list of behaviour that Gmail POP3 exhibits, that you wouldn’t expect to generally find in a POP3 server. For example, Gmail appears to ignore the DELE (delete) command from a POP3 client. Instead, it implements its own delete and archive strategy. The purpose of preparing a list is to avoid developers testing a POP3 client against the Gmail POP3 server and then assuming that all POP3 servers behave in the same way. Can anyone provide a more complete list of non-standard behaviour?

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• Why do I have to give an identifier?

  - by Knowing me knowing you

  In code: try { System.out.print(fromClient.readLine()); } catch(IOException )//LINE 1 { System.err.println("Error while trying to read from Client"); } In code line marked as LINE 1 compiler forces me to give an identifier even though I'm not using it. Why this unnatural constrain? And then if I type an identifier I'm getting warning that identifier isn't used. It just doesn't make sense to me, forcing a programmer to do something unnecesarry and surplus. And after me someone will revise this code and will be wondering if I didn't use this variable on purpouse or I just forgot. So in order to avoid that I have to write additional comment explaining why I do not use variable which is unnecessary in my code. Thanks

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• Typeclass instances for unnamed types in Scala

  - by ncreep

  How would one encode the following constraint in Scala (pseudocode)? def foo(x: T forSome { type T has a Numeric[T] instance in scope }) = { val n= implicitly[...] // obtain the Numeric instance for x n.negate(x) // and use it with x } In words: I need a type class instance for my input argument, but I don't care about the argument's type, I just need to obtain the instance and use it on my argument. It doesn't have to be an existential type, but I need to avoid type parameters in the def's signature. Thanks.

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• How to control the state of the buttons to be in present based on an event happened in a Silverlight app?

  - by vladc77

  I am trying to avoid building two buttons when I really need one. In my Silverlight app scenarios, I have few grids with a different content and buttons that control the visibility of these grids. I need to be able to show a different visual for a button when its content grid is visible. I can control states such as MouseOver and Pressed and more with visual state manage. However, I am not sure how to achieve this functionality with. I also can place an image on top of the button and switch the visibility of both but it is not perfect for what I need. I am wondering if there is any way to achieve this behavior. Any ideas are highly appreciated!

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• How big can a SQL Server row be before it's a problem?

  - by John Leidegren

  Occasionally I run into this limitation using SQL Server 2000 that a row size can not exceed 8K bytes. SQL Server 2000 isn't really state of the art, but it's still in production code and because some tables are denormalized that's a problem. However, this seems to be a non issue with SQL Server 2005. At least, it won't complain that row sizes are bigger than 8K, but what happens instead and why was this a problem in SQL Server 2000? Do I need to care about my rows growing? Should I try and avoid large rows? Are varchar(max) and varbinary(max) a solution or expensive, in terms of size in database and/or CPU time? Why do I care at all about specifying the length of a particular column, when it seems like it's just a matter of time before someones going to hit that upper limit?

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• The Scala way to use one actor per socket connection

  - by Stefan

  I am wondering how it is possible to avoid one socket connection pr. thread in Scala. I have thought a lot about it, but I always end up with some code which is listening for incoming data for each client connection. The problem is that I want to develop an application which should simultanously handle perhaps a couple of thousand connections. However I will of course not want to create a thread for each connection because of the lack of scalability and context switching. What would be the "right" way to do this. In my world it should be possible to have one actor for each connection without the need to block one thread per actor.

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• How can we protect ourselves from other third parties installing DLLs with the same names as some of

  - by Integer Poet

  Our product includes several DLLs built from open source into files with default names as delivered by the open source developers. We're careful to install the files in our own directories and we carefully manage the search path (only for our processes) to keep the loader happy. Another developer -- a towering intellect -- decided it would be easier to install their own build of some of the same open source into C:\WINDOWS under the same default DLL filenames. Consequently, when we launch a process which depends on these open source DLLs, the system searches C:\WINDOWS before our directories and finds the DLLs installed by the other developer. And they are, of course, incompatible. Ideas which have occurred to me so far: rename all our DLLs to avoid the default names, which would only make it less likely we would encounter collisions load all our DLLs by full path so the loader captures their names into RAM and doesn't search anywhere else the next time they are requested For various reasons, neither of these options is palatable at the moment. What else can we do to defend ourselves against the towering intellects of the world?

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• Perl array and hash manipulation using map

  - by somebody

  I have the following test code use Data::Dumper; my $hash = { foo => 'bar', os => 'linux' }; my @keys = qw (foo os); my $extra = 'test'; my @final_array = (map {$hash->{$_}} @keys,$extra); print Dumper \@final_array; The output is $VAR1 = [ 'bar', 'linux', undef ]; Shouldn't the elements be "bar, linux, test"? Why is the last element undefined and how do I insert an element into @final_array? I know I can use the push function but is there a way to insert it on the same line as using the map command? Basically the manipulated array is meant to be used in an SQL command in the actual script and I want to avoid using extra variables before that and instead do something like: $sql->execute(map {$hash->{$_}} @keys,$extra);

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• div Height: 0 problem in IE

  - by meo

  to clear: both my content i use this: CSS: .clr { clear: both; height: 0; /* i have tried 0.001em to */ line-height: .001em; overflow: hidden; } HTML: <div class="clr">&nbsp;</div> it works perfectly in every navigator. But in IE 7 & 8 the div still have a height of a few pixels. How can i avoid this?

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