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Update multiple rows in same query using PostgreSQL
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This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')...
– MatheusOl
Sep 14 '13 at 3:54
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How to write header row with csv.DictWriter?
...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...
Multiprocessing - Pipe vs Queue
... as a bonus; JoinableQueue() accounts for tasks when queue.task_done() is called (it doesn't even know about the specific task, it just counts unfinished tasks in the queue), so that queue.join() knows the work is finished.
The code for each at bottom of this answer...
mpenning@mpenning-T61:~$ pyt...
Delete directory with files in it?
I wonder, what's the easiest way to delete a directory with all its files in it?
33 Answers
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What are the advantages of NumPy over regular Python lists?
... Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-pr...
Swift Programming: getter/setter in stored property
...the new value that you assign will replace the one that was just set.
So all you have to do is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
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Is there a command to refresh environment variables from the command prompt in Windows?
... environment variables with a vbs script, but you need a bat script to actually change the current environment variables, so this is a combined solution.
Create a file named resetvars.vbs containing this code, and save it on the path:
Set oShell = WScript.CreateObject("WScript.Shell")
filename =...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
Is there a way to set by default for all projects removing the precompiler secure warnings that come up when using functions like scanf(). I found that you can do it by adding a line in the project option or a #define _CRT_SECURE_NO_WARNINGS in the beginning of the code.
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Get Root Directory Path of a PHP project
...IR gets the directory of the current file not the project root unless you call it in a file that is in the project root, but as php doesn't have the concept of a project all paths have to be absolute or relative to the current location
– MikeT
Nov 12 '19 at 14...
Inverse dictionary lookup in Python
...o guarantee that it returns a single value and it does not need to be lexically first only that it be the first match and that it's behavior is stable (multiple calls on same dict over time should yield same matching element). Unless dictionaries rearrange their unmodified hashes over time as other...