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In Postgresql, force unique on combination of two columns
I would like to set up a table in PostgreSQL such that two columns together must be unique. There can be multiple values of either value, so long as there are not two that share both.
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Ruby max integer
I need to be able to determine a systems maximum integer in Ruby. Anybody know how, or if it's possible?
6 Answers
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Unique combination of all elements from two (or more) vectors
I am trying to create a unique combination of all elements from two vectors of different size in R.
5 Answers
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Why can't enum's constructor access static fields?
Why can't enum's constructor access static fields and methods? This is perfectly valid with a class, but is not allowed with an enum.
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Android : Check whether the phone is dual SIM
After a lot of research on forums, now I know that there is no way to find IMSI or SIM serial number for both the SIM cards in a dual SIM phone (except for contacting the manufacturer). Now my changed question is, can we at all detect that the phone has two SIMs? I believe it can be detected with so...
Which concurrent Queue implementation should I use in Java?
From the JavaDocs:
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Javascript reduce on array of objects
Say I want to sum a.x for each element in arr .
15 Answers
15
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How do I convert an interval into a number of hours with postgres?
Say I have an interval like
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Showing data values on stacked bar chart in ggplot2
I'd like to show data values on stacked bar chart in ggplot2. Here is my attempted code
2 Answers
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Remove file from SVN repository without deleting local copy
How can I "delete" a file which is already in the SVN repository without deleting it from my file system?
5 Answers
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