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differentiate null=True, blank=True in django
When we add a database field in django we generally write:
18 Answers
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Can I concatenate multiple MySQL rows into one field?
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My need was to get ALL the data from one column. Don't use the GROUP BY clause to do this. Example : SELECT GROUP_CONCAT(emails SEPARATOR ', ') FROM users;
– Jonathan Bergeron
Jan 17 '14 at 14:04
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How to get Resource Name from Resource id
... wouldn't recommend use it if you use Proguard (minifyEnabled true), especially for getResources().getIdentifier(...
– user25
Jul 14 '18 at 22:54
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What is aspect-oriented programming?
.... People seem to talk about aspect-oriented programming, but I've never really learned what it is or how to use it. What is the basic paradigm?
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Mercurial — revert back to old version and continue from there
I'm using Mercurial locally for a project (it's the only repo there's no pushing/pulling to/from anywhere else).
7 Answers
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Custom CSS Scrollbar for Firefox
...ording to the spec. Both thin and a specific length may not do anything on all platforms, and what exactly it does is platform-specific. In particular, Firefox doesn't appear to be currently support a specific length value (this comment on their bug tracker seems to confirm this). The thin keywork d...
No submodule mapping found in .gitmodule for a path that's not a submodule
...odule mapping found in .gitmodules for path" error message.
You can check all the entries in the index which are referencing submodules:
git ls-files --stage | grep 160000
Previous answer (November 2010)
It is possible that you haven't declared your initial submodule correctly (i.e. without a...
How do I POST urlencoded form data with $http without jQuery?
... answered Jul 25 '14 at 21:19
allenhwkimallenhwkim
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How to design a database for User Defined Fields?
...rformance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns described.
Pros:
Because you indicate that some UDFs
have values for a...
It is more efficient to use if-return-return or if-else-return?
...the if condition is false anyway.
Note that Python supports a syntax that allows you to use only one return statement in your case:
return A+1 if A > B else A-1
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