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Select DISTINCT individual columns in django?
...g note in the docs about using distinct(). The above example will work but all combinations of distinct() and values() may not.
PS: it is a good idea to use lower case names for fields in a model. In your case this would mean rewriting your model as shown below:
class ProductOrder(models.Model):
...
Automatic prune with Git fetch or pull
... work is over and I don't know, I won't do a git fetch --prune and eventually I will push back the deleted branch.
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HTML tag want to add both href and onclick working
... safari in console I see warrning: [blocked] The page at fiddle.jshell.net/_display was not allowed to display insecure content from example.com - so probably this is some security issue (only on fiddle ? )
– Kamil Kiełczewski
Oct 7 '18 at 16:46
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public friend swap member function
...truct vector
{
void swap(vector&) { /* swap members */ }
};
Naturally, then, our class should too, right? Well, not really. The standard library has all sorts of unnecessary things, and a member swap is one of them. Why? Let's go on.
What we should do is identify what's canonical, and w...
How does “make” app know default target to build if no target is specified?
...e default goal; to do that, it may have to process other targets - specifically, ones the first target depends on.
The GNU Make Manual covers all this stuff, and is a surprisingly easy and informative read.
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SignalR: Why choose Hub vs. Persistent Connection?
...persistent connections.
From the highly up-voted comment below:
Partially correct. You can get topics or groups in persistent connections as well. The big difference is dispatching different types of messages. For example you have different kinds of messages and you want to send different kind...
nodeValue vs innerHTML and textContent. How to choose?
...t in firefox until FireFox 45 according to caniuse but is now supported in all major browsers.
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Bash script processing limited number of commands in parallel
... the exit status of the last
command waited for. If a job spec is given, all processes in the job
are waited for. If no arguments are given, all currently active child
processes are waited for, and the return status is zero. If neither
jobspec nor pid specifies an active child process of the...
AngularJS - difference between pristine/dirty and touched/untouched
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$pristine/$dirty tells you whether the user actually changed anything, while $touched/$untouched tells you whether the user has merely been there/visited.
This is really useful for validation. The reason for $dirty was always to avoid showing validation responses until t...
What happens to git commits created in a detached HEAD state?
...-pick [SHA] to move the commit onto an existing branch in case you accidentally committed while in detached head state
– Jan Aagaard Meier
Aug 20 '14 at 12:56
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