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MySQL, better to insert NULL or empty string?
...re differences:
A LENGTH of NULL is NULL, a LENGTH of an empty string is 0.
NULLs are sorted before the empty strings.
COUNT(message) will count empty strings but not NULLs
You can search for an empty string using a bound variable but not for a NULL. This query:
SELECT *
FROM mytable
WHERE ...
Why does this iterative list-growing code give IndexError: list assignment index out of range?
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j is an empty list, but you're attempting to write to element [0] in the first iteration, which doesn't exist yet.
Try the following instead, to add a new element to the end of the list:
for l in i:
j.append(l)
Of course, you'd never do this in practice if all you wanted to do wa...
Is it possible to write data to file using only JavaScript?
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How to get the full path of running process?
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edited Sep 21 '18 at 9:04
Uwe Keim
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answ...
How do I concatenate const/literal strings in C?
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401
In C, "strings" are just plain char arrays. Therefore, you can't directly concatenate them with...
Test if lists share any items in python
...meit
>>> timeit('bool(set(a) & set(b))', setup="a=list(range(1000));b=list(range(1000))", number=100000)
26.077727576019242
>>> timeit('any(i in a for i in b)', setup="a=list(range(1000));b=list(range(1000))", number=100000)
0.16220548999262974
Here's a graph of the execution...
Best way to implement Enums with Core Data
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130
You'll have to create custom accessors if you want to restrict the values to an enum. So, first ...
Writing a git post-receive hook to deal with a specific branch
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+50
A post-receive hook gets its arguments from stdin, in the form <oldrev> <newrev> <refname>. Since these arguments ar...
How can I create Min stl priority_queue?
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answered Mar 13 '10 at 17:37
James McNellisJames McNellis
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Regular expression to get a string between two strings in Javascript
... R. Martinho FernandesR. Martinho Fernandes
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