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Right query to get the current number of connections in a PostgreSQL DB
...ires aren't equivalent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measu...
How to attach javadoc or sources to jars in libs folder?
...-open the Eclipse project! Optionally, refresh the project by pressing F5.
Select an object of the linked library in the source code.
Open the Javadoc view in Eclipse to check the documentation (see screenshot).
Open the source code declaration (default shortcut: F3) of the selected object.
Exam...
OSX - How to auto Close Terminal window after the “exit” command executed.
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in Terminal.app
Preferences > Profiles > (Select a Profile) > Shell.
on 'When the shell exits' chosen 'Close the window'
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How can I check if a View exists in a Database?
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FOR SQL SERVER
IF EXISTS(select * FROM sys.views where name = '')
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What does jquery $ actually return?
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From Rick Strahl's description:
The jQuery Object: The Wrapped Set:
Selectors return a jQuery object known
as the "wrapped set," which is an
array-like structure that contains all
the selected DOM elements. You can
iterate over the wrapped set like an
array or access individual elem...
Linq to Sql: Multiple left outer joins
... .Where(s => s.Id == order.StatusId)
.DefaultIfEmpty()
select new { Order = order, Vendor = vendor, Status = status }
//Vendor and Status properties will be null if the left join is null
Here is another left join example
var results =
from expense in expenseDataConte...
CSS last-child selector: select last-element of specific class, not last child inside of parent?
I want to select #com19 ?
6 Answers
6
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Images can't contain alpha channels or transparencies
...rt to PNG without alpha in Preview. Simply open your image, choose export, select PNG, uncheck Alpha, and click Save. Preview also support batch export if you open all your images at once.
– Russell Ladd
Jan 7 '15 at 6:23
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Exit single-user mode
...tabase in MULTI_USER mode.
USE master
GO
DECLARE @kill varchar(max) = '';
SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(10), spid) + '; '
FROM master..sysprocesses
WHERE spid > 50 AND dbid = DB_ID('<Your_DB_Name>')
EXEC(@kill);
GO
SET DEADLOCK_PRIORITY HIGH
ALTER DATABASE [<Your_DB...
How do I prompt for Yes/No/Cancel input in a Linux shell script?
...";;
esac
done
Another method, pointed out by Steven Huwig, is Bash's select command. Here is the same example using select:
echo "Do you wish to install this program?"
select yn in "Yes" "No"; do
case $yn in
Yes ) make install; break;;
No ) exit;;
esac
done
With sele...