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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....
How to make an immutable object in Python?
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edited May 23 '17 at 12:34
Community♦
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answered Jan 28 '11 at 13:39
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Android - Activity vs FragmentActivity? [duplicate]
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3 Answers
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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...
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...
Proper way to wait for one function to finish before continuing?
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answered Feb 3 '14 at 1:24
Matt WayMatt Way
27.3k1010 gold badges6565 silver badges7575 bronze badges
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