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How to check version of python modules?
I just installed the python modules: construct and statlib with setuptools like this:
25 Answers
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If table exists drop table then create it, if it does not exist just create it
...s case than not to cover, see locking note below).
Second RENAME ... atomically replaces table definition, refer to
MySQL manual
for details.
At last, DROP ... just cleans up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
Asynchronously wait for Task to complete with timeout
...user.
And if it hasn't completed after Y milliseconds, I want to automatically request cancellation .
16 Answers
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What's the best way of structuring data on firebase?
... opposed to RDBMS, is that it's tempting to nest data because we can. Generally, you want to normalize data to some extent (just as you would do with SQL) despite the lack of join statements and queries.
You also want to denormalize in places where read efficiency is a concern. This is a technique...
Why use getters and setters/accessors?
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There are actually many good reasons to consider using accessors rather than directly exposing fields of a class - beyond just the argument of encapsulation and making future changes easier.
Here are the some of the reasons I am aware of...
Multiple levels of 'collection.defaultdict' in Python
...ng specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 12:53
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How to measure time in milliseconds using ANSI C?
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Doesn't this measure cpu time and not wall time?
– krs013
Feb 1 '15 at 4:53
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What is the difference between exit and return? [duplicate]
...hat is difference between return and exit statement in C programming when called from anywhere in a C program?
4 Answers
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Structure padding and packing
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A note though - unaligned memory access is slower on architectures that allow it (like x86 and amd64), and is explicitly prohibited on strict alignment architectures like SPARC.
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