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What's wrong with nullable columns in composite primary keys?
...s version the "ext" part of the tuple is NOT NULL but defaults to an empty string -- which is semantically (and practically) different from a NULL. A NULL is an unknown, whereas an empty string is a deliberate record of "something not being present". In other words, "empty" and "null" are different ...
Building a minimal plugin architecture in Python
...e too, although you can do a lot with just __import__, os.listdir and some string manipulation.
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Why .NET String is immutable? [duplicate]
As we all know, String is immutable. What are the reasons for String being immutable and the introduction of StringBuilder class as mutable?
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Strings as Primary Keys in SQL Database [closed]
... slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
15 Ans...
how to create a file name with the current date & time in python?
...ng datetime, this solves your problem (answers your question) of getting a string with the current time and date format you specify:
import time
timestr = time.strftime("%Y%m%d-%H%M%S")
print timestr
yields:
20120515-155045
so your filename could append or use this string.
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Concatenating two one-dimensional NumPy arrays
... the input list in various ways before hand. np.stack for example adds an extra dimension to all input arrays. Look at their source code. Only concatenate is compiled.
– hpaulj
May 26 '17 at 16:45
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Catching an exception while using a Python 'with' statement
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@ncoghlan But you can add extra try...except blocks inside with to be closer to the source of an exception that doesn't have anything to do with open().
– rbaleksandar
May 19 '17 at 14:44
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Starting python debugger automatically on error
...tically start pdb when an error is encountered? I am not against having an extra import statement at the top of the file, nor a few extra lines of code.
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What is the proper way to format a multi-line dict in Python?
...(4, 'd'),
],
}
Similarly, here's my preferred way of including large strings without introducing any whitespace (like you'd get if you used triple-quoted multi-line strings):
data = (
"iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABG"
"l0RVh0U29mdHdhcmUAQWRvYmUgSW1hZ2VSZWFkeXHJZTwAA...
How to find list of possible words from a letter matrix [Boggle Solver]
... placed importance on being able to know the exact path of every extracted string, not just the validity therein.
I also have a few adaptions in there that would theoretically permit a grid with holes in it to function, and grids with different sized lines ( assuming you get the input right and it...