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What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...
What's the difference between deque and list STL containers?
What is the difference between the two? I mean the methods are all the same. So, for a user, they work identically.
8 Answ...
How are GCC and g++ bootstrapped?
...ilt
(optional) repeat step 2 for verification purposes.
This process is called bootstrapping. It tests the compiler's capability of compiling itself and makes sure that the resulting compiler is built with all the optimizations that it itself implements.
EDIT: Drew Dormann, in the comments, point...
JSON datetime between Python and JavaScript
...
The lambda can be adapted to call the base implementation on non-datetime types, so TypeError can be raised if needed: dthandler = lambda obj: obj.isoformat() if isinstance(obj, datetime) else json.JSONEncoder().default(obj)
– Pascal...
How do I create a copy of an object in PHP?
...ass by reference is a bad idea, because it makes the effect of a function call depend on the implementation of the function, rather than on the specification. It's got nothing to do with pass by value being the default.
– Oswald
Oct 4 '13 at 7:06
...
How do I import the Django DoesNotExist exception?
...y of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation:
self.assertRaises(Answer.DoesNotExis...
No mapping found for field in order to sort on in ElasticSearch
... I still have the problem but I want the documents to be in the results in all cases even if they don't have the attribute.
– c4k
Oct 27 '13 at 15:47
...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
Skip certain tables with mysqldump
...table=schema.table2 > db-data.sql
The resulting two files are structurally sound but the dumped data is now ~500MB rather than 9GB, much better for me. I can now import these two files into another database for testing purposes without having to worry about manipulating 9GB of data or running o...
Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...