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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
What's the shortest code to cause a stack overflow? [closed]
...
All these answers and no Befunge? I'd wager a fair amount it's shortest solution of them all:
1
Not kidding. Try it yourself: http://www.quirkster.com/iano/js/befunge.html
EDIT: I guess I need to explain this one. The 1 o...
How do I append one string to another in Python?
...ugh memory to resize the string, the original
string object at *pv is deallocated, *pv is set to NULL, an "out of
memory" exception is set, and -1 is returned. Else (on success) 0 is
returned, and the value in *pv may or may not be the same as on input.
As always, an extra byte is alloc...
How can you get the Manifest Version number from the App's (Layout) XML variables?
...ntext.getPackageName(), 0).versionName;
Either of these solutions would allow for placing the version name in XML. Unfortunately there isn't a nice simple solution, like android.R.string.version or something like that.
sh...
How to convert all tables from MyISAM into InnoDB?
I know I can issue an alter table individually to change the table storage from MyISAM to InnoDB.
26 Answers
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Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
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Delete/Reset all entries in Core Data?
Do you know of any way to delete all of the entries stored in Core Data? My schema should stay the same; I just want to reset it to blank.
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Does Java have something like C#'s ref and out keywords?
...n change internals to the array or object and it will be reflected in the caller.
– Romain Hippeau
May 10 '10 at 21:27
12
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Code for Greatest Common Divisor in Python [closed]
... the result will have the same sign as b", hence gcd(1, -1) == -1 seems totally legit to me.
– Marco Bonelli
Jan 11 '15 at 2:30
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How is the undo tree used in Vim?
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See also :h undo-redo, which lists all the commands and their usage.
There are two ways to traverse the undo tree. One is to go "back in time". g+ and g- will traverse all of the nodes in the tree in chronological or reverse-chronological order (which can...