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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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SQL Server equivalent of MySQL's NOW()?
I'm a MySQL guy working on a SQL Server project, trying to get a datetime field to show the current time. In MySQL I'd use NOW() but it isn't accepting that.
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Foreign key from one app into another in Django
I'm wondering if it's possible to define a foreign key in a models.py file in Django that is a reference to a table in another app?
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Recursive directory listing in DOS
How do we achieve a recursive directory listing in DOS?
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Change text color based on brightness of the covered background area?
I've thought about the following for a while already, so now I want to know your opinions, possible solutions, and so on.
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JavaScript checking for null vs. undefined and difference between == and ===
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What does “not run” mean in R help pages?
Sometimes on an R help page the phrase "not run" appears in comments. Check out this from the help page for "with()":
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Choose newline character in Notepad++
I notice that when I load a text file, Notepad++ will recognize and use whatever the newline character in that file is, \n or \r\n .
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Await on a completed task same as task.Result?
I'm currently reading " Concurrency in C# Cookbook " by Stephen Cleary, and I noticed the following technique:
2 Answers
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NSUserDefaults removeObjectForKey vs. setObject:nil
Are the following two lines equivalent?
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