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How to properly create composite primary keys - MYSQL
...simplification of an intense setup I am working with. table_1 and table_2 both have auto-increment surrogate primary keys as the ID. info is a table that contains information about both table_1 and table_2 .
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Reload .profile in bash shell script (in unix)?
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edited Feb 20 '12 at 12:41
bluish
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What does [:] mean?
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edited Jun 24 at 20:38
answered May 29 '11 at 10:42
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What is process.env.PORT in Node.js?
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In many environments (e.g. Heroku), and as a convention, you can set the environment variable ...
When to use the JavaScript MIME type application/javascript instead of text/javascript?
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In theory, according to RFC 4329, application/javascript.
The reason it is supposed to be app...
How to use JavaScript regex over multiple lines?
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[.\n] does not work because . has no special meaning inside of [], it just means a literal .. ...
Are table names in MySQL case sensitive?
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In general:
Database and table names are not case sensitive in Windows, and case sensitive in...
What is the difference between Sublime text and Github's Atom [closed]
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How is Atom different from Sublime?
Atom is an open source text editor/IDE, built on JavaScr...
How to ALTER multiple columns at once in SQL Server
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hdoghmen
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answered Aug 12 '10 at 7:30
Neil KnightNeil K...
Test for equality among all elements of a single vector
...== 1) return(TRUE)
x <- range(x) / mean(x)
isTRUE(all.equal(x[1], x[2], tolerance = tol))
}
If you were using this more seriously, you'd probably want to remove missing values before computing the range and mean.
sh...