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Rails raw SQL example
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and then you'd need to call values on this PG::Result object to get the results array
– jobwat
Mar 26 '14 at 1:00
3
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
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If you want to insert all the columns then
insert into def select * from abc;
here the number of columns in def should be equal to abc.
if you want to insert the subsets of columns then
insert into def (col1,col2, col3 ) select scol1,scol2,...
putting current class as return type annotation [duplicate]
...e. Instead, they are preserved in __annotations__ in string form. This is called Postponed Evaluation of Annotations, introduced in PEP 563.
Also note:
Deprecation policy
Starting with Python 3.7, a __future__ import is required to use the
described functionality. No warnings are raised...
How to detect if a script is being sourced
I have a script where I do not want it to call exit if it's being sourced.
17 Answers
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What is the purpose of python's inner classes?
...dden from the outside world.
More readable, maintainable code: Nesting small classes within top-level classes places the code closer to where it is used.
The main advantage is organization. Anything that can be accomplished with inner classes can be accomplished without them.
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Counting inversions in an array
...m to do the following: Given array A[1... n] , for every i < j , find all inversion pairs such that A[i] > A[j] . I'm using merge sort and copying array A to array B and then comparing the two arrays, but I'm having a difficult time seeing how I can use this to find the number of inversions...
What's the canonical way to check for type in Python?
...ation.
One more note: in this case, if you're using Python 2, you may actually want to use:
if isinstance(o, basestring):
because this will also catch Unicode strings (unicode is not a subclass of str; both str and unicode are subclasses of basestring). Note that basestring no longer exists in P...
Linux - Replacing spaces in the file names
...umber of files in a folder, and I want to replace every space character in all file names with underscores. How can I achieve this?
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How does Apple know you are using private API?
...since I do not work in the Apple review team.
1. otool -L
This will list all libraries the app has linked to. Something clearly you should not use, like IOKit and WebKit can be detected by this.
2. nm -u
This will list all linked symbols. This can detect
Undocumented C functions such as _UIIma...
How can I dynamically create derived classes from a base class
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This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they are mandatory...