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ExecuteReader requires an open and available Connection. The connection's current state is Connectin
...n the Connection-Pool's territory
There's a good reason why ADO.NET internally manages the underlying Connections to the DBMS in the ADO-NET Connection-Pool:
In practice, most applications use only one or a few different
configurations for connections. This means that during application
exe...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
Architecture of a single-page JavaScript web application?
...x single-page JS web application be structured on the client-side? Specifically I'm curious about how to cleanly structure the application in terms of its model objects, UI components, any controllers, and objects handling server persistence.
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R memory management / cannot allocate vector of size n Mb
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Consider whether you really need all this data explicitly, or can the matrix be sparse? There is good support in R (see Matrix package for e.g.) for sparse matrices.
Keep all other processes and objects in R to a minimum when you need to make obj...
2D cross-platform game engine for Android and iOS? [closed]
... found it's 2D part with OnGUI() or GUITextures too clumsy. Also, even a smallest game done on Unity3d is at least 10MB download which is just too much for a 2D game.
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How to generate a number of most distinctive colors in R?
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I joined all qualitative palettes from RColorBrewer package. Qualitative palettes are supposed to provide X most distinctive colours each. Of course, mixing them joins into one palette also similar colours, but that's the best I can g...
What is the difference between a symbolic link and a hard link?
... (Or is it multiple inodes? Not sure.)
A file in the file system is basically a link to an inode.
A hard link, then, just creates another file with a link to the same underlying inode.
When you delete a file, it removes one link to the underlying inode. The inode is only deleted (or deletable/ove...
Is there an easy way to create ordinals in C#?
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This page gives you a complete listing of all custom numerical formatting rules:
Custom numeric format strings
As you can see, there is nothing in there about ordinals, so it can't be done using String.Format. However its not really that hard to write a function to d...
Error renaming a column in MySQL
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Keep in mind that in this solution you lose all other column definitions such as nullability, default value, etc. (see: stackoverflow.com/questions/8553130/…).
– Dejan
Jul 13 '15 at 10:50
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jQuery .data() does not work, but .attr() does
...e such a strange bug. After the doc loads, I loop some elements that originally have data-itemname="" , and I set those values using .attr("data-itemname", "someValue") .
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