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MySQL select 10 random rows from 600K rows fast
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A great post handling several cases, from simple, to gaps, to non-uniform with gaps.
http://jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL...
How to convert the ^M linebreak to 'normal' linebreak in a file opened in vim?
vim shows on every line ending ^M
35 Answers
35
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Adding new column to existing DataFrame in Python pandas
I have the following indexed DataFrame with named columns and rows not- continuous numbers:
24 Answers
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Why is unsigned integer overflow defined behavior but signed integer overflow isn't?
Unsigned integer overflow is well defined by both the C and C++ standards. For example, the C99 standard ( §6.2.5/9 ) states
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CALayers didn't get resized on its UIView's bounds change. Why?
...layer.
If I modify the view's bounds (animated), then the view itself shrinks (I checked it with a backgroundColor ), but the sublayers' size remains unchanged .
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What to put in a python module docstring? [closed]
...k, so I've read both PEP 8 and PEP 257 , and I've written lots of docstrings for functions and classes, but I'm a little unsure about what should go in a module docstring. I figured, at a minimum, it should document the functions and classes that the module exports, but I've also seen a few modu...
Clustered vs Non-Clustered
My lower level knowledge of SQL (Server 2008) is limited, and is now being challanged by our DBAs. Let me explain (I have mentioned obvious statements in the hope that I am right, but if you see something wrong, please tell me) the scenario:
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__proto__ VS. prototype in JavaScript
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__proto__ is the actual object that is used in the lookup chain to resolve methods, etc. prototype is the object that is used to build __proto__ when you create an object with new:
( new Foo ).__proto__ === Foo.prototype;
( new Foo ).prototype === undefined;
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Python: fastest way to create a list of n lists
So I was wondering how to best create a list of blank lists:
5 Answers
5
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How to iterate over the keys and values in an object in CoffeeScript?
I have an object (an "associate array" so to say - also known as a plain JavaScript object):
4 Answers
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