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Count the occurrences of DISTINCT values
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SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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Dynamically Changing log4j log level
...ation the configuration will be read and used as setting the level at runtime does not persist the level change.
UPDATE: If you are using Log4j 2 you should remove the calls to setLevel per the documentation as this can be achieved via implementation classes.
Calls to logger.setLevel() or simil...
UIView's frame, bounds, center, origin, when to use what?
UIView has the properties frame , bounds , center , and origin , and they all seem to be interrelated. Most of the time, I deal with frame when setting the position and size of a UIView . I understand that frame is using global coordinate system and bounds is using coordinate of the lo...
is there a require for json in node.js
... to include a couple of JSON files in my JavaScript code that are in the same directory as my JavaScript source file.
6 Ans...
LogCat message: The Google Play services resources were not found. Check your project configuration
...tead of showing error in my code it crashed at API level, probably I did some bad code by adding try-catch somewhere which forcefully ran the code, eventually crashing at API call (or in API). So I fixed my code and error is gone. At least this is what I think happened.
– Talha...
What is the difference between `raise “foo”` and `raise Exception.new(“foo”)`?
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Technically, the first raises a RuntimeError with the message set to "foo", and the second raises an Exception with the message set to "foo".
Practically, there is a significant difference between when you would want to use the former and when you want to use t...
Bash script to set up a temporary SSH tunnel
...e, I get Operation not permitted on drone.io continuous integration environment: muxserver_listen: link mux listener ssh-ctrl-socket.wsASkszgSBlK7kqD => ssh-ctrl-socket: Operation not permitted
– Mikko Ohtamaa
Jan 2 '15 at 2:49
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Matplotlib - global legend and title aside subplots
I've started with matplot and managed some basic plots, but now I find it hard to discover how to do some stuff I need now :(
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What is the difference between a map and a dictionary?
...map is a data structure that maps keys to values. Isn't a dictionary the same? What is the difference between a map and a dictionary 1 ?
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How do I compare two files using Eclipse? Is there any option provided by Eclipse?
...rol-click. Now right-click on one of the files, and the following context menu will appear. Select Compare With / Each Other.
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