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Create unique constraint with null columns
...or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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Where is the WPF Numeric UpDown control?
...Modifier="private" Margin="5,5,0,5" Width="50" Text="0" TextChanged="txtNum_TextChanged" />
<Button x:Name="cmdUp" x:FieldModifier="private" Margin="5,5,0,5" Content="˄" Width="20" Click="cmdUp_Click" />
<Button x:Name="cmdDown" x:FieldModifier="private" Margin="0,5,0,5" Conten...
Regex not operator
...: lookahead) this doesn't (hence: negative) match this. But it doesn't actually consume the characters it matches (hence: zero-width).
There are actually 4 combinations of lookarounds with 2 axes:
lookbehind / lookahead : specifies if the characters before or after the point are considered
positi...
Copy constructor for a class with unique_ptr
How do I implement a copy constructor for a class that has a unique_ptr member variable? I am only considering C++11.
6 A...
Can I set max_retries for requests.request?
..., predating the release of requests 1.2.1:
The requests library doesn't really make this configurable, nor does it intend to (see this pull request). Currently (requests 1.1), the retries count is set to 0. If you really want to set it to a higher value, you'll have to set this globally:
import re...
Python JSON serialize a Decimal object
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The problem was that DecimalEncoder()._iterencode(decimal.Decimal('3.9')).next() returned the correct '3.9', but DecimalEncoder()._iterencode(3.9).next() returned a generator object which would only return '3.899...' when you piled on another .next(). Generator f...
How to get the sizes of the tables of a MySQL database?
I can run this query to get the sizes of all tables in a MySQL database:
16 Answers
16...
Is there a WebSocket client implemented for Python? [closed]
...ient
Sample client code:
#!/usr/bin/python
from websocket import create_connection
ws = create_connection("ws://localhost:8080/websocket")
print "Sending 'Hello, World'..."
ws.send("Hello, World")
print "Sent"
print "Receiving..."
result = ws.recv()
print "Received '%s'" % result
ws.close()
S...
OS detecting makefile
... still use solely uname, but you have to deal with if/else blocks to check all MinGW, Cygwin, etc. variations.
The environment variable OS is always set to "Windows_NT" on different Windows versions (see %OS% environment variable on Wikipedia).
An alternative of OS is the environment variable MSVC (...
ActiveModel::ForbiddenAttributesError when creating new user
...mit(:what, :ever)
end
Update:
Here's a continuation project for CanCan called CanCanCan, which looks promising:
CanCanCan
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