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Error 1022 - Can't write; duplicate key in table
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The most likely you already have a constraint with the name iduser or idcategory in your database. Just rename the constraints if so.
Constraints must be unique for the entire database, not just for the specific table you are creating/altering.
To find out where the constraints are ...
How do I get the number of days between two dates in JavaScript?
...diff(first, second) {
// Take the difference between the dates and divide by milliseconds per day.
// Round to nearest whole number to deal with DST.
return Math.round((second-first)/(1000*60*60*24));
}
alert(datediff(parseDate(first.value), parseDate(second.value)));
<input i...
What is the difference between display: inline and display: inline-block?
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A visual answer
Imagine a <span> element inside a <div>. If you give the <span> element a height of 100px and a red border for example, it will look like this with
display: inline
display: inline-block
display: block
Code: http://jsfiddle.net/Mta2...
Dynamically creating keys in a JavaScript associative array
... edited Aug 3 '12 at 1:40
bkaid
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answered Dec 9 '08 at 1:19
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Equal sized table cells to fill the entire width of the containing table
...HTML/CSS (with relative sizing) to make a row of cells stretch the entire width of the table within which it is contained?
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CSS table column autowidth
...my last column auto size to its content?
(The last column should autosize-width to the content. Suppose i have only 1 li element it should shrink vs. having 3 li elements etc):
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Is it possible to specify condition in Count()?
...y old, but I like the NULLIF trick for such scenarios, and I found no downsides so far. Just see my copy&pasteable example, which is not very practical though, but demonstrates how to use it.
NULLIF might give you a small negative impact on performance, but I guess it should still be faster tha...
Chrome/jQuery Uncaught RangeError: Maximum call stack size exceeded
...hanks, we're struggling for performance on this anyway, so this is a great idea :-)
– Andy
Oct 5 '11 at 13:33
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How to attach debugger to iOS app after launch?
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Attach your device connected your Mac
Debug > Attach to Process by PID or Name
In the dialog sheet, enter the name of your app as it appears in the Debug navigator when started via Xcode.
If the app is already running, the debugger will attach to the running process. If it isn't running, it...
jQuery hide element while preserving its space in page layout
Is there a way in jQuery where I can hide an element, but not change the DOM when it's hidden? I'm hiding a certain element but when it's hidden, the elements below it move up. I don't want that to happen. I want the space to stay the same, but the element to be shown/hidden at will.
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