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How to use GROUP_CONCAT in a CONCAT in MySQL
...what you need.
Update
Splitting in two steps. First we get a table having all values(comma separated) against a unique[Name,id]. Then from obtained table we get all names and values as a single value against each unique id
See this explained here SQL Fiddle Demo (scroll down as it has two result se...
Finding quaternion representing the rotation from one vector to another
...
Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
What's the “Content-Length” field in HTTP header?
... Combine this answer with the answer from Tom Cabanski and you have all the information you need. In case of text you can count the number of characters since ASCII is 8 bit.
– hcpl
Sep 24 '12 at 8:45
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What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
...en Ubuntu 16.04 if not later).
Another downside is that since you aren't calling an explicit executable, it's got the potential for mistakes, and on multiuser systems security problems (if someone managed to get their executable called bash in your path, for example).
#!/usr/bin/env bash #lends yo...
C++ equivalent of StringBuffer/StringBuilder?
...f after profiling your code you discover this makes an improvement.
I normally use either std::string or std::stringstream. I have never had any problems with these. I would normally reserve some room first if I know the rough size of the string in advance.
I have seen other people make their ow...
Python exit commands - why so many and when should each be used?
...s functionality was included to help people who do not know Python. After all, one of the most likely things a newbie will try to exit Python is typing in quit.
Nevertheless, quit should not be used in production code. This is because it only works if the site module is loaded. Instead, this fun...
Using property() on classmethods
... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter:
...
How can I obfuscate (protect) JavaScript? [closed]
... use:
Google Closure Compiler
UglifyJS
UPDATE: This question was originally asked more than 10 years ago, and YUI is no longer maintained. Google Closure Compiler is still in use, and UglifyJS can be run locally via node package manager: npm install -g uglify-js
Private String Data:
Keeping st...
DynamoDB vs MongoDB NoSQL [closed]
...roughput, you just click a button. You can write scripts to scale automatically. When it's time to upgrade Dynamo, it's done for you. That is all a lot of precious stress and time not spent. If you don't have dedicated ops people, Dynamo is excellent.
So we are now going on Dynamo by default. Mongo...
Prevent onmouseout when hovering child element of the parent absolute div WITHOUT jQuery
...Listener('mouseout',onMouseOut,true);
I made a quick JsFiddle demo, with all the CSS and HTML needed, check it out...
EDIT FIXED link for cross-browser support http://jsfiddle.net/RH3tA/9/
NOTE that this only checks the immediate parent, if the parent div had nested children then you have to s...