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Rails where condition using NOT NIL
...h Rails 3:
Foo.includes(:bar).where("bars.id IS NOT NULL")
ActiveRecord 4.0 and above adds where.not so you can do this:
Foo.includes(:bar).where.not('bars.id' => nil)
Foo.includes(:bar).where.not(bars: { id: nil })
When working with scopes between tables, I prefer to leverage merge so that...
What is the in a .vimrc file?
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edited Jul 14 '15 at 5:43
Mehrad
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a...
How can I do division with variables in a Linux shell?
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edited Aug 7 '13 at 3:04
answered Aug 7 '13 at 2:59
padd...
How to make the 'cut' command treat same sequental delimiters as one?
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Try:
tr -s ' ' <text.txt | cut -d ' ' -f4
From the tr man page:
-s, --squeeze-repeats replace each input sequence of a repeated character
that is listed in SET1 with a single occurrence
of that character
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How do different retention policies affect my annotations?
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214
RetentionPolicy.SOURCE: Discard during
the compile. These annotations don't
make any s...
What does 'wb' mean in this code, using Python?
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answered Apr 19 '10 at 7:44
YOUYOU
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CPU Privilege Rings: Why rings 1 and 2 aren't used?
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114
As a hobbyist operating system writer, I found that because paging (a major part of the modern p...
Following git-flow how should you handle a hotfix of an earlier release?
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4 Answers
4
Active
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Iterating over each line of ls -l output
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249
Set IFS to newline, like this:
IFS='
'
for x in `ls -l $1`; do echo $x; done
Put a sub-shell...