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postgresql - sql - count of `true` values
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This is a good hack and gets the right answer from me. I'll accept it unless someone comes up with a shorter solution?
– EoghanM
Mar 22 '11 at 20:24
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What does tree-ish mean in Git?
...ately leads to a (sub)directory
tree (Git refers to directories as "trees" and "tree objects").
In the original poster's case, foo is a directory that he wants to
specify. The correct way to specify a (sub)directory in Git is to use this
"tree-ish" syntax (item #15 from the Git revisions documentat...
When exactly is it leak safe to use (anonymous) inner classes?
I have been reading some articles on memory leaks in Android and watched this interesting video from Google I/O on the subject .
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What is a bank conflict? (Doing Cuda/OpenCL programming)
I have been reading the programming guide for CUDA and OpenCL, and I cannot figure out what a bank conflict is. They just sort of dive into how to solve the problem without elaborating on the subject itself. Can anybody help me understand it? I have no preference if the help is in the context of CUD...
Alternative for PHP_excel
... quite as convenient for the end user as XSLX (depending on file extension and Excel version, they may get a warning message), but it's a lot easier to work with than XLS or XLSX.
http://github.com/elidickinson/php-export-data
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How to find where a method is defined at runtime?
...d occurred, a backend process failed to run. Now, we were good little boys and girls and ran rake test after every check-in but, due to some oddities in Rails' library loading, it only occurred when we ran it directly from Mongrel in production mode.
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Check if a string is null or empty in XSLT
...] null or empty" as inferred from the question, including it's pseudo-code and my own early experience with XSLT. I.e., "What is the equivalent of the following Java?":
!(categoryName == null || categoryName.equals(""))
For more details e.g., distinctly identifying null vs. empty, see johnvey's a...
Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
...ce a NumPy nxn array. I want to extract an arbitrary selection of m rows and columns of that array (i.e. without any pattern in the numbers of rows/columns), making it a new, mxm array. For this example let us say the array is 4x4 and I want to extract a 2x2 array from it.
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Array.Copy vs Buffer.BlockCopy
Array.Copy and Buffer.BlockCopy both do the same thing, but BlockCopy is aimed at fast byte-level primitive array copying, whereas Copy is the general-purpose implementation. My question is - under what circumstances should you use BlockCopy ? Should you use it at any time when you are copyi...
What's the difference between streams and datagrams in network programming?
...the call, the other answers, you say hello to each other (SYN/ACK in TCP), and then you exchange information. Once you are done, you say goodbye (FIN/ACK in TCP). If one side doesn't hear a goodbye, they will usually call the other back since this is an unexpected event; usually the client will re...