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Django select only rows with duplicate field values
... syntax is also how Django interprets you wanting to do a join. So, essentially when you try to filter on that, Django thinks you're trying to do a join with count which obviously doesn't exist. The fix is to specify a name for your annotation result, i.e. annotate(mycount=Count('id')) and then filt...
Index (zero based) must be greater than or equal to zero
...all the ArgumentException constructor overload
public static void Dostuff(Foo bar)
{
// this works
throw new ArgumentException(String.Format("Could not find {0}", bar.SomeStringProperty));
//this gives the error
throw new ArgumentException(String.Format("Could not find {0}"), bar.Some...
Chrome Extension how to send data from content script to popup.html
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Although you are definitely in the right direction (and actually pretty close to the end), there are several (imo) bad practises in your code (e.g. injecting a whole library (jquery) for such a trivial task, declaring unnecessary permissions, making superflous calls to API methods etc...
Java Synchronized Block for .class
What does this java code mean? Will it gain lock on all objects of MyClass ?
4 Answers
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'id' is a bad variable name in Python
... keyword or built-in function in any language is a bad idea, even if it is allowed.
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Mercurial .hgignore for Visual Studio 2008 projects
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Here's my standard .hgignore file for use with VS2008 that was originally modified from a Git ignore file:
# Ignore file for Visual Studio 2008
# use glob syntax
syntax: glob
# Ignore Visual Studio 2008 files
*.obj
*.exe
*.pdb
*.user
*.aps
*.pch
*.vspscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
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How to determine the memory footprint (size) of a variable?
... This is what I've done on my Ubuntu server to enable it:
sudo apt-get install libjudy-dev libjudydebian1
sudo pecl install memprof
echo "extension=memprof.so" > /etc/php5/mods-available/memprof.ini
sudo php5enmod memprof
service apache2 restart
And then in my code:
<?php
memprof_enable();
//...
How to convert an enum type variable to a string?
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There really is no beautiful way of doing this. Just set up an array of strings indexed by the enum.
If you do a lot of output, you can define an operator<< that takes an enum parameter and does the lookup for you.
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What is the size of an enum in C?
...set of enum values, but I need each enum value to be 64 bits wide. If I recall correctly, an enum is generally the same size as an int; but I thought I read somewhere that (at least in GCC) the compiler can make the enum any width they need to be to hold their values. So, is it possible to have an e...
Can (domain name) subdomains have an underscore “_” in it?
...interior characters only letters, digits, and hyphen." Which part of that allows an underscore?
– claudekennilol
Sep 16 '16 at 19:01
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