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Unable to create/open lock file: /data/mongod.lock errno:13 Permission denied
How to I get mongo to use a mounted drive on ec2? I really do not understand. I attached a volume on ec2 formatted the drive as root and start as root and yet as root I cant access? I am running on ubuntu 12.04. No other mongo is running
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How can I do an UPDATE statement with JOIN in SQL Server?
I need to update this table in SQL Server with data from its 'parent' table, see below:
16 Answers
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What does numpy.random.seed(0) do?
... I'm not very familiar with NumPy's random state generator stuff, so I'd really appreciate a layman's terms explanation of this.
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XAMPP - Port 80 in use by “Unable to open process” with PID 4! 12
...RVER)" also uses port 80 and so it should be stopped if MS-SQL sever is insalled on your machine.
– johnkarka
Nov 21 '15 at 12:01
1
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LINQ - Full Outer Join
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I don't know if this covers all cases, logically it seems correct. The idea is to take a left outer join and right outer join then take the union of the results.
var firstNames = new[]
{
new { ID = 1, Name = "John" },
new { ID = 2, Name = "Sue"...
Captured variable in a loop in C#
...ompiler is generating a class that represents the closure for your method call. It uses that single instance of the closure class for each iteration of the loop. The code looks something like this, which makes it easier to see why the bug happens:
void Main()
{
List<Func<int>> actio...
What does “error: option --single-version-externally-managed not recognized” indicate?
...suddenly started encounter the error error: option --single-version-externally-managed not recognized when pip install ing varions packages (including PyObjC and astropy ). I've never seen this error before, but it's now also showing up on travis-ci builds for which nothing has changed.
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How do I count the number of occurrences of a char in a String?
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The loop method is much faster than this. Especially when wanting to count a char instead of a String (since there is no String.replace(char, char) method). On a 15 character string, I get a difference of 6049 ns vs 26,739 ns (averaged over 100runs). Raw numbers are huge...
How to install Xcode Command Line Tools
How do I get the command-line build tools installed with the current Xcode/Mac OS X v10.8 (Mountain Lion) or later?
13 Answ...
How to count the number of files in a directory using Python
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For all kind of files, subdirectories included:
import os
list = os.listdir(dir) # dir is your directory path
number_files = len(list)
print number_files
Only files (avoiding subdirectories):
import os
onlyfiles = next(os.w...