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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 ...
CSS transition shorthand with multiple properties?
...n: height 0.3s ease-out, opacity 0.3s ease 0.5s;
Or just transition them all:
-webkit-transition: all 0.3s ease-out;
-moz-transition: all 0.3s ease-out;
-o-transition: all 0.3s ease-out;
transition: all 0.3s ease-out;
Here is a straightforward example. Here is another one with the delay propert...
Is there a way to filter network requests using Google Chrome developer tools?
... to filter out some requests using Chrome developer tools, say, filter out all image requests?
8 Answers
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What are the -Xms and -Xmx parameters when starting JVM?
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The flag Xmx specifies the maximum memory allocation pool for a Java virtual machine (JVM), while Xms specifies the initial memory allocation pool.
This means that your JVM will be started with Xms amount of memory and will be able to use a maximum of Xmx amount of ...
User recognition without cookies or local storage
...ople are so security-aware that it would be difficult to get people to install these kinds of programs on their system. This leaves you stuck with using Cookies and other, similar tools.
Cookies and other, similar tools
You might consider building a Data Profile, then using Probability tests to id...
Merge (with squash) all changes from another branch as a single commit
In Git, is there a way to merge all changes from one branch into another, but squash to a single commit at the same time?
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How to fix Python indentation
...py script that you find in the Tools/scripts/ directory of your Python installation:
Change Python (.py) files to use
4-space indents and no hard tab
characters. Also trim excess spaces
and tabs from ends of lines, and
remove empty lines at the end of
files. Also ensure the last line ...
How can I validate a string to only allow alphanumeric characters in it?
How can I validate a string using Regular Expressions to only allow alphanumeric characters in it?
10 Answers
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RESTful Authentication
...ZGRpbjpvcGVuIHNlc2FtZQ==
It's easy to implement, available by default on all browsers, but has some known drawbacks, like the awful authentication window displayed on the Browser, which will persist (there is no LogOut-like feature here), some server-side additional CPU consumption, and the fact t...
How to get a list of column names on Sqlite3 database?
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PRAGMA table_info(table_name);
will get you a list of all the column names.
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