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Does a foreign key automatically create an index?
... a constraint, a relationship between two tables - that has nothing to do with an index per se.
But it is a known fact that it makes a lot of sense to index all the columns that are part of any foreign key relationship, because through a FK-relationship, you'll often need to lookup a relating table...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
...gs that come up when using functions like scanf(). I found that you can do it by adding a line in the project option or a #define _CRT_SECURE_NO_WARNINGS in the beginning of the code.
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Explanation of JSONB introduced by PostgreSQL
PostgreSQL just introduced JSONB and it's already trending on hacker news . It would be great if someone could explain how it's different from Hstore and JSON previously present in PostgreSQL. What are its advantages and limitations and when should someone consider using it?
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Why is === faster than == in PHP?
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Because the equality operator == coerces, or converts, the data type temporarily to see if it’s equal to the other operand, whereas === (the identity operator) doesn’t need to do any converting whatsoever and thus less work is done, whic...
Is jquery a javascript library or framework? [closed]
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A library. According to the homepage, and which I agree with.
A framework is something that usually forces a certain way of implementing a solution, whereas jQuery is just a tool to make implementing what you want to do easier.
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Sort a Map by values
...follow
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edited Apr 3 '18 at 0:00
community wiki
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What's the difference between git reflog and log?
The man page says that log shows the commit logs and reflog manages reflog information. What exactly is reflog information and what does it have that the log doesn't? The log seems far more detailed.
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Bash array with spaces in elements
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I think the issue might be partly with how you're accessing the elements. If I do a simple for elem in $FILES, I experience the same issue as you. However, if I access the array through its indices, like so, it works if I add the elements either numerically or...
How to keep the console window open in Visual C++?
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Start the project with Ctrl+F5 instead of just F5.
The console window will now stay open with the Press any key to continue . . . message after the program exits.
Note that this requires the Console (/SUBSYSTEM:CONSOLE) linker option, which y...
How to get the function name from within that function?
...Function.caller and arguments.callee are both forbidden in strict mode.
Edit: nus's regex based answer below achieves the same thing, but has better performance!
In ES6, you can just use myFunction.name.
Note: Beware that some JS minifiers might throw away function names, to compress better; you ...