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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 can I do something like a FlowLayout in Android?
How can I do something like a FlowLayout in Android?
9 Answers
9
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How do I test which class an object is in Objective-C?
... This may or may not work based on whether the programmer has overridden the description method. Using [object class] or NSStringFromClass always returns the class name, though.
– futureelite7
Jan 8 '13 at 1:01
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How to output messages to the Eclipse console when developing for Android
...lag) to the Eclipse console (or log) when developing and debugging an Android app
5 Answers
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Git: how to reverse-merge a commit?
...mber' associated with the parent? Do branches have an intrinsic numerical 'id'?
– daniyalzade
Sep 5 '11 at 20:55
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jQuery append() vs appendChild()
...ppend.
You can pass multiple arguments.
var elm = document.getElementById('div1');
elm.append(document.createElement('p'),document.createElement('span'),document.createElement('div'));
console.log(elm.innerHTML);
<div id="div1"></div>
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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...
Is APC compatible with PHP 5.4 or PHP 5.5?
It doesn't seem like APC has been updated to coincide with the php 5.4 release (I wish they would have included APC in PHP core like originally planned).
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Getting an empty JQuery object
... the following code I set up a change handler on a select box to show and hide some follow up questions based on the value of the selection.
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Reconnection of Client when server reboots in WebSocket
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You should add "ws = null;" before setTimeout() to avoid multiply ws objects and eventHandligs
– Max
Oct 3 '16 at 15:32
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