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Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to ...
select and update database record with a single queryset
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Use the queryset object update method:
MyModel.objects.filter(pk=some_value).update(field1='some...
How to raise a ValueError?
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NPENPE
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HttpSecurity, WebSecurity and AuthenticationManagerBuilder
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edited Oct 1 '18 at 13:15
Patrick Cornelissen
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Adding command line options to CMake
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Peter Mortensen
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answered May 14 '11 at 7:30
beduinbeduin
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What does it mean in shell when we put a command inside dollar sign and parentheses: $(command)
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answered Aug 1 '13 at 3:53
Eric UrbanEric Urban
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Differences between Line and Branch coverage
...ere's going to be a null pointer if you call with false. However, you have 50% branch coverage in the first case, so you can see there is something missing in your testing (and often, in your code).
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Open an IO stream from a local file or url
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answered Nov 5 '08 at 3:00
Aaron HinniAaron Hinni
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MySQL WHERE: how to write “!=” or “not equals”?
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answered Jul 10 '12 at 20:53
RolandoMySQLDBARolandoMySQLDBA
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