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Difference between Django's annotate and aggregate methods?
...gt; q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been annotated with the number of authors.
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How to increment a pointer address and pointer's value?
...else?
– felipemaia
Nov 21 '11 at 15:03
@Lundin Hi, is the answer above corrected now? Thanks.
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How can I stop a Postgres script when it encounters an error?
...m Peter Eisentraut. Thank you, Peter!
http://petereisentraut.blogspot.com/2010/03/running-sql-scripts-with-psql.html
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Getting thread id of current method call
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230
NSLog(@"%@", [NSThread currentThread]);
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Pandas get topmost n records within each group
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>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...
Smart way to truncate long strings
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380
Essentially, you check the length of the given string. If it's longer than a given length n, cli...
Groovy / grails how to determine a data type?
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edited Apr 22 '10 at 8:24
answered Jan 13 '10 at 21:34
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Weird “[]” after Java method signature
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20
That's a funny Question.
In java you can say int[] a;, as well as int a[];.
From this perspecti...
How to uncompress a tar.gz in another directory
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edited Mar 7 '16 at 10:26
answered Aug 23 '13 at 12:19
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How to wait for 2 seconds?
...e required string format.
This will wait for 2 seconds:
WAITFOR DELAY '00:00:02';
The format is hh:mi:ss.mmm.
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