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Possible to do a MySQL foreign key to one of two possible tables?
...table.
Polymorphic Associations are supported by frameworks such as Rails and Hibernate. But they explicitly say that you must disable SQL constraints to use this feature. Instead, the application or framework must do equivalent work to ensure that the reference is satisfied. That is, the value ...
How does one escape backslashes and forward slashes in VIM find/search?
For instance, if I wanted to a find and replace with strings containing backward or forward slashes, how would this be accomplished in vim? Thank you!
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Insert current date in datetime format mySQL
... But it'll use MySQL server locale/timezone. If U have Apache/PHP and MySQL on different servers and timezone set incorrect in one of them U'll have different values.
– Jeff_Alieffson
Nov 24 '13 at 17:57
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How to pretty print nested dictionaries?
... U know @Ken's conventional answer is much better than this. Json already handles everything and this can give errors such: UnicodeEncodeError: 'ascii' codec can't encode character u'\xf3' in position 50: ordinal not in range(128)
– wonderwhy
Aug 27 '14 at 13:2...
How to truncate the time on a DateTime object in Python?
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Note that python 2 and python 3 docs both state that the replace() method returns a datetime object, so the correct incantation would be: dt = datetime.datetime.now().replace(hour=0, minute=0, second=0, microsecond=0)
– Br...
How do I do a not equal in Django queryset filtering?
In Django model QuerySets, I see that there is a __gt and __lt for comparitive values, but is there a __ne / != / <> ( not equals ?)
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#define macro for debug printing in C?
...on:
#ifdef DEBUG
#define DEBUG_TEST 1
#else
#define DEBUG_TEST 0
#endif
And then use DEBUG_TEST where I used DEBUG.
If you insist on a string literal for the format string (probably a good idea anyway), you can also introduce things like __FILE__, __LINE__ and __func__ into the output, which can...
What happens to an open file handle on Linux if the pointed file gets moved or deleted
What happens to an open file handle on Linux if the pointed file meanwhile gets:
7 Answers
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case-insensitive list sorting, without lowercasing the result?
... sorted(unsorted_list, key=lambda s: s.lower())
It works for both normal and unicode strings, since they both have a lower method.
In Python 2 it works for a mix of normal and unicode strings, since values of the two types can be compared with each other. Python 3 doesn't work like that, though: ...
How are booleans formatted in Strings in Python?
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What's the major difference between %r and %s?
– Alston
Sep 13 '15 at 8:17
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