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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...
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What difference is there between WebClient and HTTPWebRequest classes in .NET?

What difference is there between the WebClient and the HttpWebRequest classes in .NET? They both do very similar things. In fact, why weren't they merged into one class (too many methods/variables etc may be one reason but there are other classes in .NET which breaks that rule). ...
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Is there a TRY CATCH command in Bash

... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way. ...
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Count how many records are in a CSV Python?

...aranteed to be a fixed size, so the only way to count them is to read them all. – Martijn Pieters♦ Apr 19 '13 at 15:55 1 ...
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Usage of __slots__?

What is the purpose of __slots__ in Python — especially with respect to when I would want to use it, and when not? 11 A...
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What are copy elision and return value optimization?

... is an optimization implemented by most compilers to prevent extra (potentially expensive) copies in certain situations. It makes returning by value or pass-by-value feasible in practice (restrictions apply). It's the only form of optimization that elides (ha!) the as-if rule - copy elision can be a...
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How do I detect whether a Python variable is a function?

... If this is for Python 2.x or for Python 3.2+, you can also use callable(). It used to be deprecated, but is now undeprecated, so you can use it again. You can read the discussion here: http://bugs.python.org/issue10518. You can do this with: callable(obj) If this is for Python 3.x but ...
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How to perform file system scanning

... will not work for release versions of GO in the near future. There's actually a function in the standard lib just for this: filepath.Walk. package main import ( "path/filepath" "os" "flag" ) type visitor int // THIS CODE NO LONGER WORKS, PLEASE SEE ABOVE func (v visitor) VisitDir(p...
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How to suppress scientific notation when printing float values?

...cify how many digit after the . you wish to display, this depends on how small is the floating number). See this example: >>> a = -7.1855143557448603e-17 >>> '{:f}'.format(a) '-0.000000' as shown above, default is 6 digits! This is not helpful for our case example, so instead we...
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Gradients in Internet Explorer 9

...soft.com/testdrive/Graphics/CSSGradientBackgroundMaker/Default.html Note: all of these browsers also support rgb/rgba in place of hexadecimal notation. share | improve this answer | ...