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What are the use cases for selecting CHAR over VARCHAR in SQL?
...R (or NVARCHAR) when the length varies significantly. CHAR may also be a bit faster because all the rows are of the same length.
It varies by DB implementation, but generally, VARCHAR (or NVARCHAR) uses one or two more bytes of storage (for length or termination) in addition to the actual data. So...
What's quicker and better to determine if an array key exists in PHP?
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isset() is faster, but it's not the same as array_key_exists().
array_key_exists() purely checks if the key exists, even if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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Continuously read from STDOUT of external process in Ruby
...he output given by blender line by line to update a progress bar in a GUI. It's not really important that blender is the external process whose stdout I need to read.
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How to use web-fonts legally? [closed]
I'm a bit confused about the laws applied to web fonts. I know that it's OK to use fonts like Arial, Times Romans, Georgia, etc...I think it's illegal to use other commercial fonts.
Are there websites that provide free fonts? If there are.
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How to force garbage collection in Java?
Is it possible to force garbage collection in Java, even if it is tricky to do? I know about System.gc(); and Runtime.gc(); but they only suggest to do GC. How can I force GC?
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Why doesn't Java allow overriding of static methods?
Why is it not possible to override static methods?
22 Answers
22
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Python executable not finding libpython shared library
...IBRARY_PATH=/usr/local/lib /usr/local/bin/python
Replace /usr/local/lib with the folder where you have installed libpython2.7.so.1.0 if it is not in /usr/local/lib.
If this works and you want to make the changes permanent, you have two options:
Add export LD_LIBRARY_PATH=/usr/local/lib to your ...
What are the basic rules and idioms for operator overloading?
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Most of the work in overloading operators is boiler-plate code. That is little wonder, since operators are merely syntactic sugar, their actual work could be done by (and often is forwarded to) plain functions. But it is important that you get this boiler-plate code right. If you fail, either your...
Curious null-coalescing operator custom implicit conversion behaviour
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Thanks to everyone who contributed to analyzing this issue. It is clearly a compiler bug. It appears to only happen when there is a lifted conversion involving two nullable types on the left-hand side of the coalescing operator.
I have not yet identified where precisely things go wro...
What's the equivalent of use-commit-times for git?
...of files on my local and on my server to be in sync. This is accomplished with Subversion by setting use-commit-times=true in the config so that the last modified of each file is when it was committed.
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