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Is there any difference between GROUP BY and DISTINCT
...nce (in SQL Server, at least). Both queries use the same execution plan.
http://sqlmag.com/database-performance-tuning/distinct-vs-group
Maybe there is a difference, if there are sub-queries involved:
http://blog.sqlauthority.com/2007/03/29/sql-server-difference-between-distinct-and-group-by-dis...
What does 'super' do in Python?
...
What's the difference?
SomeBaseClass.__init__(self)
means to call SomeBaseClass's __init__. while
super(Child, self).__init__()
means to call a bound __init__ from the parent class that follows Child in the instance's Method Resolution Order (MRO).
If th...
MySql export schema without data
...
You Can Use MYSQL Administrator Tool its free
http://dev.mysql.com/downloads/gui-tools/5.0.html
you'll find many options to export ur MYSQL DataBase
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List attributes of an object
...
>>> class new_class():
... def __init__(self, number):
... self.multi = int(number) * 2
... self.str = str(number)
...
>>> a = new_class(2)
>>> a.__dict__
{'multi': 4, 'str': '2'}
>>> a.__dict__.keys(...
How to replace all dots in a string using JavaScript
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Difference between __str__ and __repr__?
What is the difference between __str__ and __repr__ in Python?
23 Answers
23
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A python class that acts like dict
...
class Mapping(dict):
def __setitem__(self, key, item):
self.__dict__[key] = item
def __getitem__(self, key):
return self.__dict__[key]
def __repr__(self):
return repr(self.__dict__)
def __len__(self):
re...
iPhone UITextField - Change placeholder text color
... 0x11561d90> valueForUndefinedKey:]: this class is not key value coding-compliant for the key _field.
– i_am_jorf
Apr 9 '14 at 19:27
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Determine .NET Framework version for dll
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Use ILSpy http://ilspy.net/
open source, free, definitely an option since now reflector is paid.
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How to find all the subclasses of a class given its name?
...ses (i.e. subclassed from object, which is the default in Python 3) have a __subclasses__ method which returns the subclasses:
class Foo(object): pass
class Bar(Foo): pass
class Baz(Foo): pass
class Bing(Bar): pass
Here are the names of the subclasses:
print([cls.__name__ for cls in Foo.__subcla...