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Simple way to calculate median with MySQL
...(1-SIGN(y.val-x.val))) = (COUNT(*)+1)/2
Make sure your columns are well indexed and the index is used for filtering and sorting. Verify with the explain plans.
select count(*) from table --find the number of rows
Calculate the "median" row number. Maybe use: median_row = floor(count / 2).
The...
Can you use if/else conditions in CSS?
... your stylesheet with your favourite server-side language. If you're using PHP, serve a style.css.php file, that looks something like this:
p {
background-position: <?php echo (@$_GET['foo'] == 'bar')? "150" : "4"; ?>px 8px;
}
In this case, you will however have a performance impact, sinc...
On delete cascade with doctrine2
...ple in order to learn how to delete a row from a parent table and automatically delete the matching rows in the child table using Doctrine2.
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Inverse dictionary lookup in Python
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python has a .index method on lists the returns the first found index with the specified value or an exception if not found... any reason why such a semantic could not be applied to dictionaries?
– Brian Jack
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MySQL high CPU usage [closed]
...log and most of the queries came from two table and the tables hadn't been indexed properly! it's only been about 10 minutes but here's the result: CPU load averages 0.48 (1 min) 0.95 (5 mins) 2.42 (15 mins) thanks very much
– Juddling
Aug 15 '09 at 18:16
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How to remove an item from an array in AngularJS scope?
... Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current index of the array you passed in.
The solution is actually pretty straightforward:
View:
<a ng-click="delete($index)">Delete</a>
Controller:
$scope.delete = function ( id...
Can the jQuery UI Datepicker be made to disable Saturdays and Sundays (and holidays)?
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There is the beforeShowDay option, which takes a function to be called for each date, returning true if the date is allowed or false if it is not. From the docs:
beforeShowDay
The function takes a date as a parameter and must return an array with [0] equal to true/false indicating wh...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
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To create these constraints through the GUI you need the "indexes and keys" dialogue not the check constraints one.
But in your case you just need to run the piece of code you already have. It doesn't need to be entered into the expression dialogue at all.
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Bring element to front using CSS
...out how to bring images to front using CSS . I've already tried setting z-index to 1000 and position to relative, but it still fails.
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jQuery AJAX cross domain
Here are two pages, test.php and testserver.php.
14 Answers
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