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how to exclude null values in array_agg like in string_agg using postgres?
...NC = fn_array_agg_notnull,
STYPE = ANYARRAY,
INITCOND = '{}'
);
Calling the second is (naturally) a little nicer looking than the first:
select array_agg_notnull(v) from x;
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im...
Writing handler for UIAlertAction
...ActionStyle.Destructive,handler: { action in
print("pressed")
}))
All the answers above are correct i am just showing another way that can be done.
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Check if a variable is a string in JavaScript
...ing both typeof and instanceof feels like good advice if your code may be called by others'. @MarkAmery's postmessage edge case matters if you're asking "what was I just postmessaged?" - but you'd expect that to be handled at the interface and not allowed to propagate. Elsewhere, it seems correct t...
MAC下如何删除NTFS格式U盘的东西? - 更多技术 - 清泛网 - 专注C/C++及内核技术
MAC下如何删除NTFS格式U盘的东西?mac上只提供了它自身磁盘格式(mac os 扩展日子)等的读写权限,只提供了读的权限给NTFS、FAT32给硬盘和U盘,我们99%使用的硬盘和U盘都是...mac上只提供了它自身磁盘格式(mac os 扩展日子)等的读...
How do I create a link using javascript?
....attr('href',desiredLink);
a.text(desiredText);
$('body').append(a);
In all the above examples you can append the anchor to any element, not just to the 'body', and desiredLink is a variable that holds the address that your anchor element points to, and desiredText is a variable that holds the te...
Multiprocessing: How to use Pool.map on a function defined in a class?
...
[p.join() for p in proc]
return [p.recv() for (p, c) in pipe]
if __name__ == '__main__':
print parmap(lambda x: x**x, range(1, 5))
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Check if something is (not) in a list in Python
... @nightcracker That makes no sense as A not in B is reduced to doing not B.__contains__(A) which is the same as what not A in B is reduced to which is not B.__contains__(A).
– Dan D.
May 2 '12 at 0:33
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The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value
...orm (headline, story, and image). ApplyPropertyChanges applies changes to all properties of the object, including your uninitialized DateTime, which is set to 0001-01-01, which is outside of the range of SQL Server's DATETIME.
Rather than using ApplyPropertyChanges, I'd suggest retrieving the obje...
Can't get Gulp to run: cannot find module 'gulp-util'
On Windows 7, I've installed gulp as explained here: http://markgoodyear.com/2014/01/getting-started-with-gulp/ :
10 Answe...
In pure functional languages, is there an algorithm to get the inverse function?
...
In some cases, yes! There's a beautiful paper called Bidirectionalization for Free! which discusses a few cases -- when your function is sufficiently polymorphic -- where it is possible, completely automatically to derive an inverse function. (It also discusses what makes...
