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Rails: select unique values from a column
...ts. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (most efficient)
Model.uniq.pluck(:rating)
# rails 5+
Model.distinct.pluck(:rating)
Update
Apparently, as of rails 5.0.0.1, it works onl...
Curly braces in string in PHP
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too much anal nitpicking about copy/paste. If it makes it easy to understand/find, then it was a good decision. +1 from me, it was exactly what I was looking for, and I did not find it on the PHP manual - maybe because they call it by the proper name, or whatever. Bu...
default select option as blank
...</select>
-- select an option -- Will be displayed by default. But if you choose an option,you will not be able select it back.
You can also hide it using by adding an empty option
<option style="display:none">
so it won't show up in the list anymore.
Option 2
If you don't want to...
What's the difference between assignment operator and copy constructor?
I don't understand the difference between assignment constructor and copy constructor in C++. It is like this:
8 Answers
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How to restart Jenkins manually?
...enkins/war/WEB-INF/jenkins-cli.jar -s http://localhost:8080/ safe-restart (if installed by rpm or deb, otherwise adjust accordingly).
– clacke
Nov 14 '13 at 3:28
13
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How do I reflect over the members of dynamic object?
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If the IDynamicMetaObjectProvider can provide the dynamic member names, you can get them. See GetMemberNames implementation in the apache licensed PCL library Dynamitey (which can be found in nuget), it works for ExpandoObjec...
How to sort in-place using the merge sort algorithm?
I know the question is not too specific.
10 Answers
10
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What's the fastest way to delete a large folder in Windows?
I want to delete a folder that contains thousands of files and folders. If I use Windows Explorer to delete the folder it can take 10-15 minutes (not always, but often). Is there a faster way in Windows to delete folders?
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Checkout old commit and make it a new commit [duplicate]
... commits, and I want to make the version 3 commits ago as the new version. If I do git checkout xxxx , it creates a new branch and it seems like I can only merge it? Could I make this the new "master version"?
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Iterating over every two elements in a list
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It does a different thing. Your version only yields half the number of pairs compared to the itertools recipe function with the same name. Of course yours is faster...
– Sven Marnach
Mar 22 '11 a...