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Count the occurrences of DISTINCT values
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Just changed Amber's COUNT(*) to COUNT(1) for the better performance.
SELECT name, COUNT(1) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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What does DIM stand for in Visual Basic and BASIC?
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answered Jun 23 '09 at 16:01
Patrick McDonaldPatrick McDonald
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push_back vs emplace_back
...nction void emplace_back(Type&& _Val) provided by MSCV10 is non conforming and redundant, because as you noted it is strictly equivalent to push_back(Type&& _Val).
But the real C++0x form of emplace_back is really useful: void emplace_back(Args&&...);
Instead of taking a va...
Java Pass Method as Parameter
...da expression consists of the following:
A comma-separated list of formal parameters enclosed in parentheses. The CheckPerson.test method contains one parameter, p,
which represents an instance of the Person class.Note: You
can omit the data type of the parameters in a lambda expression....
How to construct a set out of list items in python?
... on darwin Type "help", "copyright", "credits" or "license" for more information. >>> x = [1,2,3] >>> set(x) set([1, 2, 3]) >>>
– opus111
Dec 20 '17 at 18:49
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Worst security hole you've seen? [closed]
... in particular, pass an SQL query through the query string. It's the worst form of SQL injection, and it takes no effort at all to find vulnerable sites.
With minor tweaks, I've been able to find unprotected installations of phpMyAdmin, unprotected installations of MySQL, query strings containing u...
Django rest framework, use different serializers in the same ModelViewSet
...rs I've created this small python package that gives this functionality in form a child class of ModelViewset. Here is how it works.
from drf_custom_viewsets.viewsets.CustomSerializerViewSet
from myapp.serializers import DefaltSerializer, CustomSerializer1, CustomSerializer2
class MyViewSet(Custom...
Why should I care that Java doesn't have reified generics?
...hat. Method selection is done at compile time when the compile-time type information is available.
– Tom Hawtin - tackline
Dec 18 '09 at 13:25
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What is the difference between exit and return? [duplicate]
...nearly) the same thing is in the main() function, as a return from main performs an exit().
In most C implementations, main is a real function called by some startup code that does something like int ret = main(argc, argv); exit(ret);. The C standard guarantees that something equivalent to this hap...
Type hinting a collection of a specified type
...strated below.
Update 1
As of May 2015, PEP0484 (Type Hints) has been formally accepted. The draft implementation is also available at github under ambv/typehinting.
Original Answer
As of Aug 2014, I have confirmed that it is not possible to use Python 3 type annotations to specify types with...