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How to implement a unique index on two columns in rails
I have a table and I'm trying to add a unique index on two columns. Those columns are also indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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How can I change the copyright template in Xcode 4?
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Xcode 4 (and above) stores this on a per-project basis.
If you select the project in the Project Navigator (Cmd-1) and open the File Inspector (Cmd-Opt-1), you'll see a field for "Organization" under "Project Document".
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How can I filter a Django query with a list of values?
I'm sure this is a trivial operation, but I can't figure out how it's done.
3 Answers
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How can I see the current value of my $PATH variable on OS X?
returns:
4 Answers
4
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What is the difference between os.path.basename() and os.path.dirname()?
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Both functions use the os.path.split(path) function to split the pathname path into a pair; (head, tail).
The os.path.dirname(path) function returns the head of the path.
E.g.: The dirname of '/foo/bar/item' is '/foo/bar'.
The o...
how to check if List element contains an item with a Particular Property Value
How to check if element of pricePublicList contains certain value. To be more precise, I want to check if there exists pricePublicModel.Size == 200 ? Also, if this element exists, how to know which one it is?
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How to get rspec-2 to give the full trace associated with a test failure?
Right now if I run my test suite using rake spec I get an error:
6 Answers
6
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What is “incremental linking”?
I've looked at Microsoft's MSDN and all around the web, but I still haven't been able to get a really good idea of what it is.
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Xcode — what is $(SRCROOT)?
I am looking at an Xcode project that uses some libraries. The project was created on a different computer, so I need to update some paths. The library search paths all start with $(SRCROOT) . What does that mean?
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How to get the last element of a slice?
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For just reading the last element of a slice:
sl[len(sl)-1]
For removing it:
sl = sl[:len(sl)-1]
See this page about slice tricks
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