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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 ...
Clear back stack using fragments
...tp://groups.google.com/group/android-developers/browse_thread/thread/d2a5c203dad6ec42
I ended up just using:
FragmentManager fm = getActivity().getSupportFragmentManager();
for(int i = 0; i < fm.getBackStackEntryCount(); ++i) {
fm.popBackStack();
}
But could equally have used somethin...
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...
What is the purpose of willSet and didSet in Swift?
...eld. For instance, in that example:
class Foo {
var myProperty: Int = 0 {
didSet {
print("The value of myProperty changed from \(oldValue) to \(myProperty)")
}
}
}
myProperty prints its old and new value every time it is modified. With just getters and setters,...
How to restore to a different database in sql server?
...
10 Answers
10
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Writing a git post-receive hook to deal with a specific branch
...
+50
A post-receive hook gets its arguments from stdin, in the form <oldrev> <newrev> <refname>. Since these arguments ar...
How to get the full path of running process?
... |
edited Sep 21 '18 at 9:04
Uwe Keim
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answ...
How can I create Min stl priority_queue?
...
answered Mar 13 '10 at 17:37
James McNellisJames McNellis
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Changing route doesn't scroll to top in the new page
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580
The problem is that your ngView retains the scroll position when it loads a new view. You can in...
Regular expression to get a string between two strings in Javascript
... R. Martinho FernandesR. Martinho Fernandes
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