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Simple way to transpose columns and rows in SQL?
...it is able to expand to include newly added document, without altering the script.
Performance breakdown
The major limitation of transposing rows into columns using CURSOR is a disadvantage that is linked to using cursors in general – they come at significant performance cost. This is because the...
How can I negate the return-value of a process?
...able answer — works with antique shells
In a Bourne (Korn, POSIX, Bash) script, I use:
if ...command and arguments...
then : it succeeded
else : it failed
fi
This is as portable as it gets. The 'command and arguments' can be a pipeline or other compound sequence of commands.
A not command
T...
What is the purpose of the -m switch?
...w modules to be located using the Python module namespace for execution as scripts. The motivating examples were standard library modules such as pdb and profile, and the Python 2.4 implementation is fine for this limited purpose.
So you can specify any module in Python's search path this way, not...
On select change, get data attribute value
...
Vanilla Javascript:
this.querySelector(':checked').getAttribute('data-id')
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What is output buffering?
..., your HTML is sent to the browser in pieces as PHP processes through your script. With output buffering, your HTML is stored in a variable and sent to the browser as one piece at the end of your script.
Advantages of output buffering for Web developers
Turning on output buffering alone decreases t...
Difference between single and double square brackets in Bash
...h manual section on conditional constructs.
Use [] whenever you want your script to be portable across shells. Use [[]] if you want conditional expressions not supported by [] and don't need to be portable.
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What are Makefile.am and Makefile.in?
...generate the Makefile.in file (the .am stands for automake).
The configure script typically seen in source tarballs will use the Makefile.in to generate a Makefile.
The configure script itself is generated from a programmer-defined file named either configure.ac or configure.in (deprecated). I pref...
Importing CommonCrypto in a Swift framework
...is to create an Aggregate target called "CommonCryptoModuleMap" with a Run Script phase to generate the module map automatically and with the correct Xcode/SDK path:
The Run Script phase should contain this bash:
# This if-statement means we'll only run the main script if the CommonCryptoModule...
Import a module from a relative path
...a safe solution for inclusion of modules relatively to the location of the script.
I assume that you want to do this, because you need to include a set of modules with your script. I use this in production in several products and works in many special scenarios like: scripts called from another dir...
jQuery get selected option value (not the text, but the attribute 'value')
...ion text ' + $(this).find('option').filter(':selected').text());
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<select>
<option value="1" selected>1 - Text</option>
<option value="2">2 - Text</option>...