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You can't specify target table for update in FROM clause
...e problem is that MySQL, for whatever inane reason, doesn't allow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't reference that table in an inner query (you ...
How can I change an element's class with JavaScript?
...asses
Modern browsers have added classList which provides methods to make it easier to manipulate classes without needing a library:
document.getElementById("MyElement").classList.add('MyClass');
document.getElementById("MyElement").classList.remove('MyClass');
if ( document.getElementById("MyEl...
Semi-transparent color layer over background-image?
...ould like to put a pattern as background. This pattern is gray. So to make it a little more nice, I would like to put a light transparent color "layer" over. Below is what I tried but which did not work. Is there a way to put the colored layer over the background image?
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Check if image exists on server using JavaScript?
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Function is awesome. I put it in my collection :) I thought fileExists would be better name because this function does not check if image exists on server. It check if file is accessible from server. There is no check if that file actually is an image....
How to use enums as flags in C++?
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The "correct" way is to define bit operators for the enum, as:
enum AnimalFlags
{
HasClaws = 1,
CanFly = 2,
EatsFish = 4,
Endangered = 8
};
inline AnimalFlags operator|(AnimalFlags a, AnimalFlags b)
{
return static_cast<Anim...
Grab a segment of an array in Java without creating a new array on heap
...is worthy of deletion. The answer by @unique72 is correct. Imma let this edit sit for a bit and then I shall delete this answer.)
I don't know of a way to do this directly with arrays without additional heap allocation, but the other answers using a sub-list wrapper have additional allocation fo...
How do I capture the output of a script if it is being ran by the task scheduler?
...008, how do I go about capturing the output of a script that is being ran with the windows task scheduler?
9 Answers
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Django 1.7 - makemigrations not detecting changes
As the title says, I can't seem to get migrations working.
29 Answers
29
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Swift compiler error: “non-modular header inside framework module”
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I accept this answer even it is the same as I stated.
– Stephan
Jun 22 '14 at 18:34
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How to set HTTP header to UTF-8 using PHP which is valid in W3C validator?
I have several PHP pages echoing out various things into HTML pages with the following code.
6 Answers
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