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How to drop SQL default constraint without knowing its name?
...llowing script will generate the command to drop the constraint and dynamically execute it.
declare @schema_name nvarchar(256)
declare @table_name nvarchar(256)
declare @col_name nvarchar(256)
declare @Command nvarchar(1000)
set @schema_name = N'MySchema'
set @table_name = N'Department'
set @col_...
How can I create a copy of an object in Python?
...would like to create a copy of an object. I want the new object to possess all properties of the old object (values of the fields). But I want to have independent objects. So, if I change values of the fields of the new object, the old object should not be affected by that.
...
Sharing a URL with a query string on Twitter
...epending on the URL). Tweetdeck doesn't seem to handle twitter.com URLs at all.
– Pierre-Luc Paour
Oct 1 '12 at 14:47
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What is the 'instanceof' operator used for in Java?
... Dog is Dog
dog instanceof Object // true - Object is the parent type of all objects
However, with Object animal = new Animal();,
animal instanceof Dog // false
because Animal is a supertype of Dog and possibly less "refined".
And,
dog instanceof Cat // does not even compile!
This is beca...
Many-to-many relationship with the same model in rails?
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For reference: the Rails documentation on the subject. There's a section called “Many-to-many”, and of course the documentation on the class methods themselves.
Simplest scenario, uni-directional, no additional fields
This is the most compact in code.
I'll start out with this basic schema fo...
Difference between wait() and sleep()
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A wait can be "woken up" by another thread calling notify on the monitor which is being waited on whereas a sleep cannot. Also a wait (and notify) must happen in a block synchronized on the monitor object whereas sleep does not:
Object mon = ...;
synchronized (mon) {
...
What's the difference between using CGFloat and float?
I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
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Numpy: Divide each row by a vector element
...
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Math - mapping numbers
...))
– Chris Chiasson
Mar 9 '17 at 18:32
To reverse the direction, the formula is ( (X-A)/(A-B) * (C-D) ) * -1 + D
...
How to split a large text file into smaller files with equal number of lines?
...a large (by number of lines) plain text file that I'd like to split into smaller files, also by number of lines. So if my file has around 2M lines, I'd like to split it up into 10 files that contain 200k lines, or 100 files that contain 20k lines (plus one file with the remainder; being evenly divi...