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Rails raw SQL example
How can I convert this code to raw sql and use in rails? Because When I deploy this code in heroku,there is a request timeout error.I think this will be faster if I use raw sql.
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How to map a composite key with JPA and Hibernate?
...y the specification also applies. So here they are:
2.1.4 Primary Keys and Entity Identity
...
A composite primary key must
correspond to either a single
persistent field or property or to a
set of such fields or properties as
described below. A primary key class
must be defi...
Comprehensive beginner's virtualenv tutorial? [closed]
I've been hearing the buzz about virtualenv lately, and I'm interested. But all I've heard is a smattering of praise, and don't have a clear understanding of what it is or how to use it.
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What is the difference between gravity and layout_gravity in Android?
I know we can set the following values to the android:gravity and android:layout_gravity properties:
20 Answers
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Xcode 6 Bug: Unknown class in Interface Builder file
I upgraded to Xcode 6 beta 4 and now my App continuously crashes with the message
52 Answers
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Performance of foreach, array_map with lambda and array_map with static function
...2 compare with mcfedr's answer below for additional results without XDebug and a more recent PHP version.
function lap($func) {
$t0 = microtime(1);
$numbers = range(0, 1000000);
$ret = $func($numbers);
$t1 = microtime(1);
return array($t1 - $t0, $ret);
}
function useForeach($numbers) {...
How do I iterate through each element in an n-dimensional matrix in MATLAB?
... answered Apr 17 '09 at 2:46
AndrewAndrew
1,15777 silver badges55 bronze badges
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NodeJS - Error installing with NPM
... am using Windows 8.1, can anyone tell me what is the problem i am facing, and why is this installation not working. There seems to be a problem with the buffertools dependency, thats far as i can think. Dont know how maybe fix this?
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Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...s a more complete version that shows more differences between [ (aka test) and [[.
The following table shows that whether a variable is quoted or not, whether you use single or double brackets and whether the variable contains only a space are the things that affect whether using a test with or wit...
Checking for a dirty index or untracked files with Git
...;/dev/null| grep "^M" | wc -l)
# Get number of files that are uncommitted and not added
expr $(git status --porcelain 2>/dev/null| grep "^ M" | wc -l)
# Get number of total uncommited files
expr $(git status --porcelain 2>/dev/null| egrep "^(M| M)" | wc -l)
Note: The 2>/dev/null filters...