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“Insert if not exists” statement in SQLite
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edited Apr 13 '18 at 6:12
answered Oct 12 '13 at 17:38
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What is the difference between UNION and UNION ALL?
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182
The implication of this, is that union is much less performant as it must scan the result for duplicates
– Matthew Wa...
Proper way to use **kwargs in Python
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488
You can pass a default value to get() for keys that are not in the dictionary:
self.val2 = kwa...
How to remove specific elements in a numpy array
...specific question:
import numpy as np
a = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
index = [2, 3, 6]
new_a = np.delete(a, index)
print(new_a) #Prints `[1, 2, 5, 6, 8, 9]`
Note that numpy.delete() returns a new array since array scalars are immutable, similar to strings in Python, so each time a c...
while (1) Vs. for (;;) Is there a speed difference?
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218
In perl, they result in the same opcodes:
$ perl -MO=Concise -e 'for(;;) { print "foo\n" }'
a ...
callback to handle completion of pipe
...steampowered
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answered Jul 12 '12 at 8:59
PickelsPickels
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Anyway to prevent the Blue highlighting of elements in Chrome when clicking quickly?
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edited Apr 26 '18 at 0:52
answered Jan 8 '14 at 18:33
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Appending an element to the end of a list in Scala
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edited Nov 11 '18 at 15:41
Unmesha SreeVeni
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SQL SELECT speed int vs varchar
...the space usage of different date types:
int fields occupy between 2 and 8 bytes, with 4 being usually more than enough ( -2147483648 to +2147483647 )
character types occupy 4 bytes plus the actual strings.
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C# - Attribute to Skip over a Method while Stepping in Debug Mode
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edited Jul 9 '18 at 14:19
Eonasdan
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an...