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MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in there?
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Logical operators for boolean indexing in Pandas
...Error: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True ...
What is the best way to exit a function (which has no return value) in python before the function en
...hod i use return, it still keep running code behind a. exit should be like php exit(), it breaks the program instantly.
– TomSawyer
Sep 24 '17 at 18:29
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What do I use for a max-heap implementation in Python?
... amazed that there IS such a built-in solution in heapq. But then it is totally unreasonable that it is NOT even slightly mentioned at all in the official document! WTF!
– RayLuo
Apr 21 '15 at 6:48
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Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
Using python's eval() vs. ast.literal_eval()?
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datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
method of iterating over sqlalchemy model's defined columns?
...l exclude SA magic attributes, but will not exclude the relations. So basically it might load the dependencies, parents, children etc, which is definitely not desirable.
But it is actually much easier because if you inherit from Base, you have a __table__ attribute, so that you can do:
for c in Jo...
When should I use Kruskal as opposed to Prim (and vice versa)?
...in a very straightforward way : http://www.thestudentroom.co.uk/showthread.php?t=232168.
Kruskal's algorithm will grow a solution from the cheapest edge by adding the next cheapest edge, provided that it doesn't create a cycle.
Prim's algorithm will grow a solution from a random vertex by adding ...
What is the difference between server side cookie and client side cookie?
...rence between creating cookies on the server and on the client? Are these called server side cookies and client side cookies? Is there a way to create cookies that can only be read on the server or on the client?
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How do I list all files of a directory?
How can I list all files of a directory in Python and add them to a list ?
21 Answers
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