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ROW_NUMBER() in MySQL
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I want the row with the single highest col3 for each (col1, col2) pair.
That's a groupwise maximum, one of the most commonly-asked SQL questions (since it seems like it should be easy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0....
What is the difference between an expression and a statement in Python?
...duced to some kind of "value", which can be any Python object. Examples:
3 + 5
map(lambda x: x*x, range(10))
[a.x for a in some_iterable]
yield 7
Statements (see 1, 2), on the other hand, are everything that can make up a line (or several lines) of Python code. Note that expressions are stateme...
Why do Java webapps use .do extension? Where did it come from?
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How to make an immutable object in Python?
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edited May 23 '17 at 12:34
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answered Jan 28 '11 at 13:39
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What is the maximum possible length of a query string?
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Why can't decimal numbers be represented exactly in binary?
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Decimal numbers can be represented exactly, if you have enough space - just not by floating bi...
Get class name of django model
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edited Aug 30 '10 at 11:06
answered Aug 30 '10 at 10:29
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