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Difference between Control Template and DataTemplate in WPF
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Typically a control is rendered for its own sake, and doesn't reflect underlying data. For example, a Button wouldn't be bound to a business object - it's there purely so it can be clicked on. A ContentControl or ListBox, however,...
How to save all the variables in the current python session?
I want to save all the variables in my current python environment. It seems one option is to use the 'pickle' module. However, I don't want to do this for 2 reasons:
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Referring to a Column Alias in a WHERE Clause
... statslogsummary
WHERE ( DATEDIFF(day, maxlogtm, GETDATE() > 120)
Normally you can't refer to field aliases in the WHERE clause. (Think of it as the entire SELECT including aliases, is applied after the WHERE clause.)
But, as mentioned in other answers, you can force SQL to treat SELECT to be ...
Viewing all defined variables [duplicate]
...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such).
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How to access environment variable values?
...os.environ
import os
print(os.environ['HOME'])
Or you can see a list of all the environment variables using:
os.environ
As sometimes you might need to see a complete list!
# using get will return `None` if a key is not present rather than raise a `KeyError`
print(os.environ.get('KEY_THAT_MIGH...
Can I pass parameters by reference in Java?
... Also, an array of length 1 can be used to create a reference if you really want to confuse people :)
– Christoffer
Jul 1 '09 at 12:18
2
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How to initialize all members of an array to the same value?
... array in C (not C++ if that makes a difference). I want to initialize all members of the same value.
23 Answers
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
Python speed testing - Time Difference - milliseconds
...e timedelta! For timing purposes always use c.total_seconds().
You can do all sorts of maths with datetime.timedelta, eg:
>>> c / 10
datetime.timedelta(0, 0, 431654)
It might be more useful to look at CPU time instead of wallclock time though ... that's operating system dependant though...
Get all object attributes in Python? [duplicate]
Is there a way to get all attributes/methods/fields/etc. of an object in Python?
4 Answers
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