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Query a parameter (postgresql.conf setting) like “max_connections”
... SHOW, such as minimum
and maximum values.
For your original request:
SELECT *
FROM pg_settings
WHERE name = 'max_connections';
Finally, there is current_setting(), which can be nested in DML statements:
SELECT current_setting('max_connections');
Related:
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What is fastest children() or find() in jQuery?
To select a child node in jQuery one can use children() but also find().
6 Answers
6
...
Twitter Bootstrap Tabs: Go to Specific Tab on Page Reload or Hyperlink
...).ready(function(event) {
$('ul.nav.nav-tabs a:first').tab('show'); // Select first tab
$('ul.nav.nav-tabs a[href="'+ window.location.hash+ '"]').tab('show'); // Select tab by name if provided in location hash
$('ul.nav.nav-tabs a[data-toggle="tab"]').on('shown', function (event) { //...
How to change the background color of a UIButton while it's highlighted?
...ged" forState:UIControlStateHighlighted];
[myButton addTarget:self action:@selector(buttonHighlight:) forControlEvents:UIControlEventTouchDown];
[myButton addTarget:self action:@selector(buttonNormal:) forControlEvents:UIControlEventTouchUpInside];
Option 2:
Return an image made from the highligh...
How to downgrade or install an older version of Cocoapods
...e default version, so you have to sudo gem uninstall cocoapods first, then select 1.0.0 as the version to remove. Not sure if this has always been the behavior, but sudo gem install cocoapods -v 0.39.0 alone didn't do the trick for me once I had 1.0.0.
– fullofsquirrels
...
Bash: Strip trailing linebreak from output
...ine character you want to remove, you can use 'head' from GNU coreutils to select everything except the last byte. This should be quite quick:
head -c -1 log.txt
Also, for completeness, you can quickly check where your newline (or other special) characters are in your file using 'cat' and the 'sh...
Django rest framework nested self-referential objects
... by the OP here and at the same time support this solution for dynamically selecting fields to be serialized. Yprez's solution causes an infinite recursion or requires additional complications to avoid the recursion and properly select fields.
– Louis
Jul 24 '...
mysql create user if not exists
...
I use
SELECT EXISTS (SELECT DISTINCT user FROM mysql.user WHERE user = "username") as is_user
should return 1 if exists or 0 if it does not
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Is there a CSS selector for elements containing certain text?
I am looking for a CSS selector for the following table:
18 Answers
18
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MySQL: Sort GROUP_CONCAT values
... see http://dev.mysql.com/doc/refman/...tions.html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
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