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postgresql COUNT(DISTINCT …) very slow
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holy queries batman! This sped up my postgres count distinct from 190s to 4.5 whoa!
– rogerdpack
Nov ...
How can I see the size of files and directories in linux? [closed]
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answered Jul 30 '12 at 10:59
mk..mk..
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Which MySQL data type to use for storing boolean values
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For MySQL 5.0.3 and higher, you can use BIT. The manual says:
As of MySQL 5.0.3, the BIT data type is used to store bit-field
values. A type of BIT(M) enables storage of M-bit values. M can range
from 1 to 64.
Otherwise, according to t...
Dictionaries and default values
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edited Jan 23 '19 at 5:30
Solomon Ucko
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How do I declare and initialize an array in Java?
...s/api/java/util/stream/IntStream.html
int [] myIntArray = IntStream.range(0, 100).toArray(); // From 0 to 99
int [] myIntArray = IntStream.rangeClosed(0, 100).toArray(); // From 0 to 100
int [] myIntArray = IntStream.of(12,25,36,85,28,96,47).toArray(); // The order is preserved.
int [] myIntArray =...
Get decimal portion of a number with JavaScript
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Use 1, not 2.
js> 2.3 % 1
0.2999999999999998
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How to calculate date difference in JavaScript?
...icktoofay
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Creating JS object with Object.create(null)?
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They are not equivalent. {}.constructor.prototype == Object.prototype while Object.create(null)...
Combining two Series into a DataFrame in pandas
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In [4]: pd.concat([s1, s2], axis=1).reset_index()
Out[4]:
index s1 s2
0 A 1 3
1 B 2 4
Note: This extends to more than 2 Series.
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Get the week start date and week end date from week number
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answered Aug 12 '09 at 16:14
Robin DayRobin Day
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