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How to get progress from XMLHttpRequest
... {
if (req.readyState == 4)
{
//run any callback here
}
};
req.send();
}
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Select DISTINCT individual columns in django?
...g note in the docs about using distinct(). The above example will work but all combinations of distinct() and values() may not.
PS: it is a good idea to use lower case names for fields in a model. In your case this would mean rewriting your model as shown below:
class ProductOrder(models.Model):
...
PostgreSQL: Show tables in PostgreSQL
...terface,
First, choose your database
\c database_name
Then, this shows all tables in the current schema:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
...
Resizing an image in an HTML5 canvas
...
So what do you do if all the browsers (actually, Chrome 5 gave me quite good one) won't give you good enough resampling quality? You implement them yourself then! Oh come on, we're entering the new age of Web 3.0, HTML5 compliant browsers, super ...
How does “make” app know default target to build if no target is specified?
...e default goal; to do that, it may have to process other targets - specifically, ones the first target depends on.
The GNU Make Manual covers all this stuff, and is a surprisingly easy and informative read.
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Print the contents of a DIV
...rs later, this will produce "a.browser is undefined" because the .browser call has been removed in jquery 1.9
– KingsInnerSoul
Aug 24 '18 at 20:58
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Difference between shadowing and overriding in C#?
...dow
public override int Bar() {return 1;} //override
}
then when you call this:
A clA = new A();
B clB = new B();
Console.WriteLine(clA.Foo()); // output 5
Console.WriteLine(clA.Bar()); // output 5
Console.WriteLine(clB.Foo()); // output 1
Console.WriteLine(clB.Bar()); // output 1
//now let'...
How to test if parameters exist in rails
...re asking about existence. You might need to differentiate:
Not there at all.
There but nil.
There but false.
There but an empty string.
as well. Hard to say without more details of your precise situation.
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What to do with branch after merge
...he merge, it's safe to delete the branch:
git branch -d branch1
Additionally, git will warn you (and refuse to delete the branch) if it thinks you didn't fully merge it yet. If you forcefully delete a branch (with git branch -D) which is not completely merged yet, you have to do some tricks to ge...
AngularJS - difference between pristine/dirty and touched/untouched
...
$pristine/$dirty tells you whether the user actually changed anything, while $touched/$untouched tells you whether the user has merely been there/visited.
This is really useful for validation. The reason for $dirty was always to avoid showing validation responses until t...