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The object 'DF__*' is dependent on column '*' - Changing int to double
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Try this:
Remove the constraint DF_Movies_Rating__48CFD27E before changing your field type.
The constraint is typically created automatically by the DBMS (SQL Server).
To see the constraint associated with the table, expand the table attributes in Object ex...
What's the pythonic way to use getters and setters?
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Try this: Python Property
The sample code is:
class C(object):
def __init__(self):
self._x = None
@property
def x(self):
"""I'm the 'x' property."""
print("getter of x called")
return self._x
@x.setter
def x(self, value):
print("sette...
unique object identifier in javascript
... var id = 0;
Object.id = function(o) {
if ( typeof o.__uniqueid == "undefined" ) {
Object.defineProperty(o, "__uniqueid", {
value: ++id,
enumerable: false,
// This could go either way, depending on your...
remove None value from a list without removing the 0 value
... - it's just for scientific purposes)
>>> from operator import is_not
>>> from functools import partial
>>> L = [0, 23, 234, 89, None, 0, 35, 9]
>>> filter(partial(is_not, None), L)
[0, 23, 234, 89, 0, 35, 9]
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Python __call__ special method practical example
I know that __call__ method in a class is triggered when the instance of a class is called. However, I have no idea when I can use this special method, because one can simply create a new method and perform the same operation done in __call__ method and instead of calling the instance, you can c...
Can I redirect the stdout in python into some sort of string buffer?
...ngIO import StringIO # Python3 use: from io import StringIO
import sys
old_stdout = sys.stdout
sys.stdout = mystdout = StringIO()
# blah blah lots of code ...
sys.stdout = old_stdout
# examine mystdout.getvalue()
share
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Convert sqlalchemy row object to python dict
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You may access the internal __dict__ of a SQLAlchemy object, like the following::
for u in session.query(User).all():
print u.__dict__
share
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im...
Dictionary vs Object - which is more efficient and why?
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Have you tried using __slots__?
From the documentation:
By default, instances of both old and new-style classes have a dictionary for attribute storage. This wastes space for objects having very few instance variables. The space consumption can ...
How do I use raw_input in Python 3
I am using Python 3.1 and can't get the raw_input to "freeze" the dos pop-up. The book I'm reading is for Python 2.5 and I'm using Python 3.1
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Python Sets vs Lists
... as lists, except for their immutability.
Iterating
>>> def iter_test(iterable):
... for i in iterable:
... pass
...
>>> from timeit import timeit
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(1...