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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 ...
Rails: create on has_one association
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answered Oct 1 '10 at 13:59
sepp2ksepp2k
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How to show git log history for a sub directory of a git repo?
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254
From directory foo/, use
git log -- A
You need the '--' to separate <path>.. from th...
Creating functions in a loop
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Aran-Fey
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answered Aug 7 '10 at 19:09
Alex MartelliAlex ...
Maven: Command to update repository after adding dependency to POM
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Fixed stroke width in SVG
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edited May 12 '16 at 18:55
Zach Saucier
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an...
Python Threading String Arguments
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305
You're trying to create a tuple, but you're just parenthesizing a string :)
Add an extra ',':
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Capitalize or change case of an NSString in Objective-C
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answered Apr 7 '11 at 19:52
RegexidentRegexident
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How to search in array of object in mongodb
... is:
db.users.find({awards: {$elemMatch: {award:'National Medal', year:1975}}})
$elemMatch allows you to match more than one component within the same array element.
Without $elemMatch mongo will look for users with National Medal in some year and some award in 1975s, but not for users with Nati...
Friend declaration in C++ - difference between public and private
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sharptoothsharptooth
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