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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...
Side-by-side plots with ggplot2
I would like to place two plots side by side using the ggplot2 package , i.e. do the equivalent of par(mfrow=c(1,2)) .
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Do I really need to encode '&' as '&'?
I'm using an ' & ' symbol with HTML5 and UTF-8 in my site's <title> . Google shows the ampersand fine on its SERPs, as do all the browsers in their titles.
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What characters are valid for JavaScript variable names?
Which characters can be used for naming a JavaScript variable?
12 Answers
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Unzip a file with php
I want to unzip a file and this works fine
12 Answers
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In what cases do I use malloc and/or new?
I see in C++ there are multiple ways to allocate and free data and I understand that when you call malloc you should call free and when you use the new operator you should pair with delete and it is a mistake to mix the two (e.g. Calling free() on something that was created with the new ...
Can jQuery provide the tag name?
I've got several elements on a HTML page which have the same class - but they're different element types. I want to find out the tag name of the element as I loop over them - but .attr doesn't take "tag" or "tagname".
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Create a list from two object lists with linq
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This can easily be done by using the Linq extension method Union. For example:
var mergedList = list1.Union(list2).ToList();
This will return a List in which the two lists are merged and doubles are removed. If you don't specify a comparer in the Union extension method like in my example, it wil...
Programmatically change the src of an img tag
How can I change the src attribute of an img tag using javascript?
9 Answers
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In Clojure, when should I use a vector over a list, and the other way around?
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Once again, it seems I've answered my own question by getting impatient and asking it in #clojure on Freenode. Good thing answering your own questions is encouraged on Stackoverflow.com :D
I had a quick discussion with Rich Hickey, and here is the gist of it.
[12:21] <Raynes> V...