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Import module from subfolder
... What would the syntax be if previously Foo1 was in the parent directory and one coded something like from Foo1 import *. Is there a way to achieve that same effect so you don't have to prefix everything with Foo1?
– jxramos
Apr 12 '17 at 23:41
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Why would anybody use C over C++? [closed]
...would want to choose C over C++. C doesn't seem to get nearly as much flak and if C++ has all these problems why can't you just restrict yourself to the C subset? What are your thoughts/experience?
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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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Reverse a string in Python
...tended slice syntax. It works by doing [begin:end:step] - by leaving begin and end off and specifying a step of -1, it reverses a string.
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PostgreSQL return result set as JSON array?
...
TL;DR
SELECT json_agg(t) FROM t
for a JSON array of objects, and
SELECT
json_build_object(
'a', json_agg(t.a),
'b', json_agg(t.b)
)
FROM t
for a JSON object of arrays.
List of objects
This section describes how to generate a JSON array of objects, with eac...
Automatically import modules when entering the python or ipython interpreter
... documentation:
If this is the name of a readable file, the Python commands in that
file are executed before the first prompt is displayed in interactive
mode. The file is executed in the same namespace where interactive
commands are executed so that objects defined or imported in it can b...
Correct way to use get_or_create?
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@zypro It's like create(), create object and save it all in one step and doesn't need any save()
– Amin Mir
Jun 19 at 6:05
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Where to define custom error types in Ruby and/or Rails?
...ou define exceptions in this way:
gem_dir/lib/gem_name/exceptions.rb
and defined as:
module GemName
class AuthenticationError < StandardError; end
class InvalidUsername < AuthenticationError; end
end
an example of this would be something like this in httparty
For Ruby on Rails
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How to increase font size in the Xcode editor?
... match the mindset of software engineers that make 100+ character variable and method names. Enough of my complaining)
I'll modify a previous post for the current version.
Close any projects you have open in Xcode (Otherwise the Font window will be inaccessible while a project is open.)
Go to XCo...
Empty set literal?
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@andy That's not an empty set - that's a set containing the number 1. You don't need the trailing comma by the way - that's only required for tuples.
– sepp2k
Jan 19 '15 at 13:12
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