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Postgis installation: type “geometry” does not exist
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203
I had the same problem, but it was fixed by running following code
CREATE EXTENSION postgis;
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Explaining Apache ZooKeeper
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436
In a nutshell, ZooKeeper helps you build distributed applications.
How it works
You may descr...
How do I get an empty array of any size in python?
... Sven MarnachSven Marnach
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93
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Determine the number of NA values in a column
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321
You're over-thinking the problem:
sum(is.na(df$col))
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SQL/mysql - Select distinct/UNIQUE but return all columns?
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edited May 23 '17 at 12:34
Community♦
111 silver badge
answered May 25 '11 at 16:05
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How to get first element in a list of tuples?
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253
>>> a = [(1, u'abc'), (2, u'def')]
>>> [i[0] for i in a]
[1, 2]
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How to find the most recent file in a directory using .NET, and without looping?
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321
how about something like this...
var directory = new DirectoryInfo("C:\\MyDirectory");
var my...
What is the correct syntax for 'else if'?
I'm a new Python programmer who is making the leap from 2.6.4 to 3.1.1. Everything has gone fine until I tried to use the 'else if' statement. The interpreter gives me a syntax error after the 'if' in 'else if' for a reason I can't seem to figure out.
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Fastest way to determine if an integer's square root is an integer
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35 Answers
35
Active
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How can I pass command-line arguments to a Perl program?
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edited Oct 24 '16 at 19:37
Stefan van den Akker
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