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MySQL - Rows to Columns
I tried to search posts, but I only found solutions for SQL Server/Access. I need a solution in MySQL (5.X).
12 Answers
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Why do we need the “event” keyword while defining events?
...derstand why do we need the "event" keyword while defining events, when we can do the same thing without using "event" keyword, just by using the delegates.
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C++ code file extension? .cc vs .cpp [closed]
I have seen C++ code saved as both .cc and .cpp files. Is there a difference between the two?
17 Answers
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Do I cast the result of malloc?
In this question , someone suggested in a comment that I should not cast the result of malloc , i.e.
29 Answers
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In C++, what is a virtual base class?
I want to know what a " virtual base class " is and what it means.
11 Answers
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How to dump a dict to a json file?
I have a dict like this:
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Python syntax for “if a or b or c but not all of them”
I have a python script that can receive either zero or three command line arguments. (Either it runs on default behavior or needs all three values specified.)
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What are naming conventions for MongoDB?
Is there a set of preferred naming conventions for MongoDB entitites such as databases, collections, field names?
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What is a word boundary in regex?
I am using Java regexes in Java 1.6 (to parse numeric output, among other purposes) and cannot find a precise definition of \b ("word boundary"). I had assumed that -12 would be an "integer word" (matched by \b\-?\d+\b ) but it appears that this does not work. I'd be grateful to know of ways ...
How to get the first line of a file in a bash script?
...t in a bash variable the first line of a file. I guess it is with the grep command, but it is any way to restrict the number of lines?
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