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MySQL: multiple tables or one table with many columns?
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Any time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but...
Why does Python print unicode characters when the default encoding is ASCII?
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Thanks to bits and pieces from various replies, I think we can stitch up an explanation.
By trying to print an unicode string, u'\xe9', Python implicitly try to encode that string using the encoding scheme currently stored in sys.stdout.e...
Is JavaScript a pass-by-reference or pass-by-value language?
...er that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).
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What exactly are unmanaged resources?
...g Dispose on that object, or (in C#) using the using statement which will handle calling Dispose for you.
If you neglect to Dispose of your unmanaged resources correctly, the garbage collector will eventually handle it for you when the object containing that resource is garbage collected (this is "...
Hash collision in git
...f? Well the Moon is made up of about 1047 atoms. So if we have 10 Moons... and you randomly pick one atom on one of these moons... and then go ahead and pick a random atom on them again... then the likelihood that you'll pick the same atom twice, is the likelihood that two given git commits will hav...
ReactJS state vs prop
This may be treading that line between answerable and opinionated, but I'm going back and forth as to how to structure a ReactJS component as complexity grows and could use some direction.
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Localization and internationalization, what's the difference?
... Some other reasons to think of them separately: Internationalization QA and localization QA have different test cases, Internationalization is a one-time cost (more or less), and so the more languages you localize to, the higher your ROI. i18n is generally more costly than l10n to any one locale....
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...o do an upsert, which is what MySQL calls INSERT ... ON DUPLICATE UPDATE and the standard supports as part of the MERGE operation.
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Checking if a double (or float) is NaN in C++
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According to the IEEE standard, NaN values have the odd property that comparisons involving them are always false. That is, for a float f, f != f will be true only if f is NaN.
Note that, as some comments below have pointed out, not all compilers ...
What is trunk, branch and tag in Subversion? [duplicate]
What is a trunk, branch and tag in Subversion and what are the best practices to use them?
9 Answers
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