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MySQL: Sort GROUP_CONCAT values
... see http://dev.mysql.com/doc/refman/...tions.html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
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:not(:empty) CSS selector is not working?
I'm having a heck of a time with this particular CSS selector which does not want to work when I add :not(:empty) to it. It seems to work fine with any combination of the other selectors:
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MySQL > Table doesn't exist. But it does (or it should)
...e table name I'm using is off. So table is called 'db' but I used 'DB' in select statement. Make sure the case is the same.
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qmake: could not find a Qt installation of ''
...of qt you want use.
You could also use qtchooser - a wrapper used to select between Qt development binary versions.
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How to use arguments from previous command?
... see:
$ echo ace
By the way, you could have put the echo on the line by selecting argument 0:
Press Alt-0 Alt-Ctrl-y
Edit:
To answer the question you added to your original:
You can press Alt-0 then repeatedly press Alt-. to step through the previous commands (arg 0). Similarly Alt-- then rep...
How to echo shell commands as they are executed
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You can also toggle this for select lines in your script by wrapping them in set -x and set +x, for example,
#!/bin/bash
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if [[ ! -e $OUT_FILE ]];
then
echo "grabbing $URL"
set -x
curl --fail --noproxy $SERV -s -S $URL -o $OUT_FILE
set +x...
How to generate serial version UID in Intellij
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very nice, very easy to install. you can install that from plugins menu, select install from disk, select the jar file you unpacked in the lib folder. restart, control + ins, and it pops up to generate serial UID from menu. love it. :-)
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Lock, mutex, semaphore… what's the difference?
... just one active thread from many others within one process. The other non selected threads (@ acquiring this object) are put to sleep.
[No interprocess capability, very primitive object].
2) Mutex Semaphore (aka Mutex)= Kernel object used for allowing the execution of just one active thread from ...
How to use a switch case 'or' in PHP
...le switch(), and when I'm working in a C-ish language I really miss having Select Case, which is really a shorthand way of saying "there's a big block of if, else if, else-if... here".
– Stan Rogers
Oct 9 '10 at 7:50
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How to fix error “Updating Maven Project”. Unsupported IClasspathEntry kind=4?
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Right-click on your project, select Maven -> Remove Maven Nature.
Open you terminal, go to your project folder and do mvn eclipse:clean
Right click on your Project and select “Configure -> Convert into Maven Project”
Now you got “Unsupporte...