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MySQL, update multiple tables with one query
...ookID is very important, without it The Books table update would happen to all rows and not only for the row with the specified id. Some lessons are learned the hard way, this one was learned in the terrifing way.
– nheimann1
Mar 24 '15 at 15:06
...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
Checking if an instance's class implements an interface?
...
As therefromhere points out, you can use class_implements(). Just as with Reflection, this allows you to specify the class name as a string and doesn't require an instance of the class:
interface IInterface
{
}
class TheClass implements IInterface
{
}
$interfaces = cl...
throw Error('msg') vs throw new Error('msg')
...this is explicitly stated in the specification:
... Thus the function call Error(…) is equivalent to the object creation expression new Error(…) with the same arguments.
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What's the algorithm to calculate aspect ratio?
...re that's been changed from 16:9 to 5:4 - I still remember the incredibly tall, thin cowboys I used to watch in my youth on television before letter-boxing was introduced. You may be better off having one different image per aspect ratio and just resize the correct one for the actual screen dimensio...
Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
...
Getting an empty JQuery object
...tion about it, but I solved it by using PHP instead of jQuery so I can't really dig more into it right now.
– cregox
Mar 2 '11 at 19:02
2
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How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
...
JavaScript OOP in NodeJS: how?
...onstructor.apply( this, arguments );
}
//Pointless override to show super calls
//note that for performance (e.g. inlining the below is impossible)
//you should do
//method.$getAge = _super.getAge;
//and then use this.$getAge() instead of super()
method.getAge = function() {
return _super.getAge...
Use underscore inside Angular controllers
...derscore, it attaches itself to the window object, and so is available globally.
So you can use it from Angular code as-is.
You can also wrap it up in a service or a factory, if you'd like it to be injected:
var underscore = angular.module('underscore', []);
underscore.factory('_', ['$window', fu...