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How to change the name of a Django app?
...lt;newAppName>_modelName. For mysql too I think it is the same (as mentioned by @null_radix)
(For Django >= 1.7) Update the django_migrations table to avoid having your previous migrations re-run: UPDATE django_migrations SET app='<NewAppName>' WHERE app='<OldAppName>'. Note: there...
What is the best algorithm for overriding GetHashCode?
...) == XorHash(y, x) for all x, y
By the way, the earlier algorithm is the one currently used by the C# compiler for anonymous types.
This page gives quite a few options. I think for most cases the above is "good enough" and it's incredibly easy to remember and get right. The FNV alternative is sim...
Algorithm to return all combinations of k elements from n
.... Let's say {1,2,3} we can say that the difference between the elements is one and in order and minimal. {1,2,4} has one change and is lexicographically number 2. So the number of 'changes' in the last place accounts for one change in the lexicographical ordering. The second place, with one change {...
iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]
I was just wondering with how should we deal with the iPhone 5 bigger screen size.
8 Answers
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I need to store postal codes in a database. How big should the column be?
...eds editing, since the similar looking postal code for Malta has a generic one like "AAA NNNN". I would not mind to have even 15 characters because it could only be less problem later if we have to adjust column length, also with right use of data types, it should not take all 15 characters anyway (...
What is the simplest SQL Query to find the second largest value?
...this will not return a result if there are no records before the requested one.
– andig
Oct 8 '15 at 11:42
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Count number of days between two dates
...ing that end_date and start_date are both of class ActiveSupport::TimeWithZone in Rails, then you can use:
(end_date.to_date - start_date.to_date).to_i
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Define a lambda expression that raises an Exception
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There is more than one way to skin a Python:
y = lambda: (_ for _ in ()).throw(Exception('foobar'))
Lambdas accept statements. Since raise ex is a statement, you could write a general purpose raiser:
def raise_(ex):
raise ex
y = lamb...
How to correctly use the extern keyword in C
...e the variable itself, i.e. doesn't allocate any memory. This needs to be done somewhere else. Thus it's important if you want to import the variable from somewhere else. For functions, this only tells the compiler that linkage is extern. As this is the default (you use the keyword "static" to indic...
open read and close a file in 1 line of code
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If you really need a one-liner, it is possible to put the output = f.read() part on the same line after the :.
– Karl Knechtel
Nov 4 '11 at 16:03
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