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find vs find_by vs where
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Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
...lready have. It doesn't need to be entered into the expression dialogue at all.
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Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...
What is the Python equivalent of Matlab's tic and toc functions?
...e stuff
Sometimes I find this technique more convenient than timeit - it all depends on what you want to measure.
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Visual Studio window which shows list of methods
...io, is there a window which shows list of methods in the active class? A small window like the Solution Explorer would be great. In Eclipse, there is one.
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Why does sys.exit() not exit when called inside a thread in Python?
...and I'm confused as to why the following code snippet would not exit when called in the thread, but would exit when called in the main thread.
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Dashed line border around UIView
...t@2x.png and test@3x.png with size of 240x240 and 360x360 which is used in all the apple device automatically with it's related name. (i.e. test.png is use in iPhone 4, test@2x will useful for iPhone 4s, 5, 5s, 6, 6s and twst@3x will useful for iPhone 6 plus, 6s plus.
– Paras J...
When are you supposed to use escape instead of encodeURI / encodeURIComponent?
... section B.2.1.2 escape and the introduction text of Annex B says:
... All of the language features and behaviours specified in this annex have one or more undesirable characteristics and in the absence of legacy usage would be removed from this specification. ...
... Programmers should not us...
Using “super” in C++
... the first time C++ was standardized.
Dag Bruck proposed this extension, calling the base class "inherited." The proposal mentioned the multiple inheritance issue, and would have flagged ambiguous uses. Even Stroustrup was convinced.
After discussion, Dag Bruck (yes, the same person making the p...
How can I setup & run PhantomJS on Ubuntu?
... to add one additional symlink to /usr/bin/, and I did direct symlinks for all 3 - see below.
I'm installing on Ubuntu server Natty Narwhal.
This is exactly what I did.
cd /usr/local/share
sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf ...