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Inserting multiple rows in mysql
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When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.
Optimizing INSERT Statements
You can find more tips on how to speed up your insert statements on the link above.
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What does the slash mean in help() output?
...python functions.
Also see the Argument Clinic documentation:
To mark all parameters as positional-only in Argument Clinic, add a / on a line by itself after the last parameter, indented the same as the parameter lines.
and the (very recent addition to) the Python FAQ:
A slash in the argu...
How to work with complex numbers in C?
...h:
creal(z1): get the real part (for float crealf(z1), for long double creall(z1))
cimag(z1): get the imaginary part (for float cimagf(z1), for long double cimagl(z1))
Another important point to remember when working with complex numbers is that functions like cos(), exp() and sqrt() must be repl...
Which $_SERVER variables are safe?
...ttacker can also control and is therefore a source of an attack. This is called a "tainted" variable, and is unsafe.
2 An...
#1071 - Specified key was too long; max key length is 1000 bytes
...tle have been answered before, but please do read on. I've read thoroughly all the other questions/answers on this error before posting.
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How can I add new keys to a dictionary?
...ted to strings). dict.update can also take another dictionary, but I personally prefer not to explicitly create a new dictionary in order to update another one.
– bgusach
Feb 13 '19 at 8:38
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How do you get the logical xor of two variables in Python?
...e not comparing apples to oranges, is "if xor( isApple(x), isApple(y) )" really clearer than "if isApple(x) != isApple(y)" ? Not to me!
– AmigoNico
May 21 '12 at 18:27
109
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How do I use installed packages in PyCharm?
...you use the os (ex. apt-get), or pip in a virtualenv, packages will be installed to a location already on the path.
In your example, GNU Radio is installed to the system Python 2's standard site-packages location, which is already in the path. Pointing PyCharm at the correct interpreter is enough;...
In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
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Note that groupname can also be the ac...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...lations are needed and used when ordering and comparing strings. It's generally a good idea to have a single, unique collation used throughout your database - don't use different collations within a single table or database - you're only asking for trouble....
Once you've settled for one single col...