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MySQL, better to insert NULL or empty string?
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221
By using NULL you can distinguish between "put no data" and "put empty data".
Some more differe...
getting date format m-d-Y H:i:s.u from milliseconds
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15 Answers
15
Active
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Using querySelector with IDs that are numbers
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109
It is valid, but requires some special handling. From here: http://mathiasbynens.be/notes/css...
Why does this iterative list-growing code give IndexError: list assignment index out of range?
...ample below), and later, overwrite the values in specific positions:
i = [1, 2, 3, 5, 8, 13]
j = [None] * len(i)
#j == [None, None, None, None, None, None]
k = 0
for l in i:
j[k] = l
k += 1
The thing to realise is that a list object will not allow you to assign a value to an index that doe...
Deep copy of a dict in python
... }
d2 = copy.deepcopy(d)
Python 2 or 3:
Python 3.2 (r32:88445, Feb 20 2011, 21:30:00) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import copy
>>> my_dict = {'a': [1, 2, 3], 'b': [4, 5, 6]}
>>> my_copy =...
How to fallback to local stylesheet (not script) if CDN fails
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11 Answers
11
Active
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PHP Pass by reference in foreach [duplicate]
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146
Because on the second loop, $v is still a reference to the last array item, so it's overwritte...
What really is a deque in STL?
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190
A deque is somewhat recursively defined: internally it maintains a double-ended queue of chunk...
Turn off constraints temporarily (MS SQL)
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217
You can disable FK and CHECK constraints only in SQL 2005+. See ALTER TABLE
ALTER TABLE foo NO...
Haskell: Where vs. Let
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1: The problem in the example
f :: State s a
f = State $ \x -> y
where y = ... x ...
is the parameter x. Things in the where clause can refer only to the parameters of the function f (there are none) and things in o...