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Does a UNIQUE constraint automatically create an INDEX on the field(s)?
...rick. When the constraint is defined using user_id first and then email it doesn't show up in EXPLAIN. Are you aware of this?
– gremo
Mar 19 '12 at 3:14
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Does JavaScript have a method like “range()” to generate a range within the supplied bounds?
In PHP, you can do...
62 Answers
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Parse string to DateTime in C#
...e.Parse() will try figure out the format of the given date, and it usually does a good job. If you can guarantee dates will always be in a given format then you can use ParseExact():
string s = "2011-03-21 13:26";
DateTime dt =
DateTime.ParseExact(s, "yyyy-MM-dd HH:mm", CultureInfo.InvariantC...
how does multiplication differ for NumPy Matrix vs Array classes?
...with matrices. However, unlike octave (which I was using till recently), * doesn't perform matrix multiplication, you need to use the function matrixmultipy(). I feel this makes the code very unreadable.
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How to delete shared preferences data from App in Android
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Clearing the preferences file does not appear to actually delete it. In my own tests by watching the "Data" usage listed in the App Info panel, creating a new SharedPreference file adds 4KB to this value but using editor.clear().commit() does not reduce t...
Calculate the execution time of a method
...ing a StopWatch. He said the reason for this is that the Stopwatch in .NET does not take into account CPU affinity, and therefore, if your thread moves from one core to another, the StopWatch doesn't take into account the execution time across the other cores; only the one where the thread began exe...
Multi-project test dependencies with gradle
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This does not work in Gradle 1.3 since sourceSets is no longer a public property of a project.
– David Pärsson
Jan 14 '13 at 10:39
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What is the difference between Session.Abandon() and Session.Clear()
... like throwing away the whole shelf.
You say:
When I test Session, it doesn't makes any change when I Abandon the session.
This is correct while you are doing it within one request only.
On the next request the session will be different. But the session ID can be reused so that the id will r...
What is function overloading and overriding in php?
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PHP doesn't support overloading, though.
– Sasha Chedygov
Jun 8 '10 at 4:40
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How to raise a ValueError?
...wever I would like it to raise a ValueError when the specified character does not occur in a string.
4 Answers
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