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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...
Memory footprint of Haskell data types
... instance of these constructors and shares it amongst all uses.
A word is 4 bytes on a 32-bit machine, and 8 bytes on a 64-bit machine.
So e.g.
data Uno = Uno a
data Due = Due a b
an Uno takes 2 words, and a Due takes 3.
The Int type is defined as
data Int = I# Int#
now, Int# takes one wor...
Plotting time in Python with Matplotlib
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How to get last items of a list in Python?
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545
You can use negative integers with the slicing operator for that. Here's an example using the p...
RVM is not working in ZSH
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answered Jan 21 '11 at 5:24
intellidiotintellidiot
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HintPath vs ReferencePath in Visual Studio
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Set default syntax to different filetype in Sublime Text 2
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How to undo the effect of “set -e” which makes bash exit immediately if any command fails?
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314
With set +e. Yeah, it's backward that you enable shell options with set - and disable them with...
Scaling Node.js
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Load balancing
Most probably for the most simple sites you don't need any scaling at all. Just...
Showing commits made directly to a branch, ignoring merges in Git
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edited Jan 2 '19 at 13:42
Joshua Pinter
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a...