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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):
...
Format a date using the new date time API
...in JavaScript or DateTime in Perl) are based on the concept of a universal all-purpose unique temporal type (in German there is the poetic expression "eierlegende Wollmilchsau"). In this design there cannot be an unsupported field. But the price is high: Many time problems cannot be adequately handl...
What is the purpose of the '@' symbol in CSS?
...ructs. The @ syntax itself, though, as I mentioned, is not new.
These are all known in CSS as at-rules. They're special instructions for the browser, not directly related to styling of (X)HTML/XML elements in Web documents using rules and properties, although they do play important roles in control...
GDB corrupted stack frame - How to debug?
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Those bogus adresses (0x00000002 and the like) are actually PC values, not SP values. Now, when you get this kind of SEGV, with a bogus (very small) PC address, 99% of the time it's due to calling through a bogus function pointer. Note that virtual calls in C++ are implemented ...
Is there a good Valgrind substitute for Windows?
...
oriporip
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'size_t' vs 'container::size_type'
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The standard containers define size_type as a typedef to Allocator::size_type (Allocator is a template parameter), which for std::allocator<T>::size_type is typically defined to be size_t (or a compatible type). So for the standard case, they are the same.
However, if you us...
Why can't the C# constructor infer type?
...type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
6 Answers
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Does Parallel.ForEach limit the number of active threads?
...on't start 1000 threads - yes, it will limit how many threads are used. Parallel Extensions uses an appropriate number of cores, based on how many you physically have and how many are already busy. It allocates work for each core and then uses a technique called work stealing to let each thread proc...
Why isn't String.Empty a constant?
...ing.cs.
The Empty constant holds the empty
string value. We need to call the
String constructor so that the
compiler doesn't mark this as a
literal.
Marking this as a literal would mean
that it doesn't show up as a field
which we can access from native.
I found this informati...