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Difference between left join and right join in SQL Server [duplicate]
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@SilapAliyev That's actually a very good question. Can anyone answer? :D
– Ian Chu Te
Jan 8 '16 at 2:46
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...tent database, and that's one of the good reasons to use a database. Especially if you have several applications requesting it (or just one application but with a direct mode and a batch mode using different sources).
With MySQL you do not have advanced constraints like you would have in postgreSQL...
Can a decorator of an instance method access the class?
I have something roughly like the following. Basically I need to access the class of an instance method from a decorator used upon the instance method in its definition.
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vbscript output to console
...aples - Not w/ the stock WScript.Echo. I suppose, if you wanted to stay totally within WScript you could do something horrifyingly dodgy like Exec'ing off another process to do a "SendKeys" to the parent process to close the MessageBox.
– Evan Anderson
Jun 22 '...
Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
Publish to S3 using Git?
...we wanted). Next create an S3 bucket to store your repository in, let’s call it git-repos, and then create a git repository to upload:
s3cmd mb s3://git-repos
mkdir chef-recipes
cd chef-recipes
git init
touch README
git add README
git commit README
git remote add origin amazon-s3://.jgit@git-repo...
Where should signal handlers live in a django project?
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I actually like to make them classmethods of the model itself. That keeps everything within one class, and means you don't have to worry about importing anything.
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How to implement a binary tree?
...ice implementation. I'm just here to point out some style stuff. python usually does node is not None instead of your (node!=None). Also, you can use the __str__ function instead of the printTree method.
– Jeff Mandell
Oct 18 '15 at 2:30
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Can someone explain __all__ in Python?
I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files. Can someone explain what this does?
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List attributes of an object
...ict__
Then you can test what type is with type() or if is a method with callable().
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