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Is there a REAL performance difference between INT and VARCHAR primary keys?
...a natural key instead of a surrogate key. Only you can assess if the benefit of this is significant in your application.
That is, you can measure the queries in your application that are the most important to be speedy, because they work with large volumes of data or they are executed very frequ...
Where is the WPF Numeric UpDown control?
Getting into the first serious WPF project. It seems like there are a lot of basic controls flat out missing. Specifically, I am looking for the Numeric UpDown control. Was there an out of band release that I missed? Really don't feel like writing my own control.
...
Abstract classes in Swift Language
...e a way to create an abstract class in the Swift Language, or is this a limitation just like Objective-C? I'd like to create a abstract class comparable to what Java defines as an abstract class.
...
Python function attributes - uses and abuses [closed]
...ly use function attributes as storage for annotations. Suppose I want to write, in the style of C# (indicating that a certain method should be part of the web service interface)
class Foo(WebService):
@webmethod
def bar(self, arg1, arg2):
...
then I can define
def webmethod(func...
Recommended way of making React component/div draggable
I want to make a draggable (that is, repositionable by mouse) React component, which seems to necessarily involve global state and scattered event handlers. I can do it the dirty way, with a global variable in my JS file, and could probably even wrap it in a nice closure interface, but I want to kno...
Backbone View: Inherit and extend events from parent
...: 'onclick'
},
//Override this event hash in
//a child view
additionalEvents: {
},
events : function() {
return _.extend({},this.originalEvents,this.additionalEvents);
}
});
var ChildView = ParentView.extend({
additionalEvents: {
'click' : ' onclickChild'
}
})...
Inserting multiple rows in mysql
... rows. To do this, include multiple lists of column values, each enclosed within parentheses and separated by commas.
Example:
INSERT INTO tbl_name
(a,b,c)
VALUES
(1,2,3),
(4,5,6),
(7,8,9);
Source
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How do you detect where two line segments intersect? [closed]
... can find t and u such that:
p + t r = q + u s
Cross both sides with s, getting
(p + t r) × s = (q + u s) × s
And since s × s = 0, this means
t (r × s) = (q − p) × s
And therefore, solving for t:
t = (q − p) × s / (r × s)
In the same way, we can solve for ...
Parse a .py file, read the AST, modify it, then write back the modified source code
I want to programmatically edit python source code. Basically I want to read a .py file, generate the AST , and then write back the modified python source code (i.e. another .py file).
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Run certain code every n seconds [duplicate]
...?
For example, the program would go through whatever code I had, then once it had been 5 seconds (with time.sleep() ) it would execute that code. I would be using this to update a file though, not print Hello World.
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