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How to retrieve an element from a set without removing it?
Suppose the following:
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NULL values inside NOT IN clause
...t different records counts for what I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could us...
Python: Why is functools.partial necessary?
...oes functools.partial offer that you can't get through lambdas?
Not much in terms of extra functionality (but, see later) – and, readability is in the eye of the beholder.
Most people who are familiar with functional programming languages (those in the Lisp/Scheme families in particular) appear ...
What are the differences between B trees and B+ trees?
In a b-tree you can store both keys and data in the internal and leaf nodes , but in a b+ tree you have to store the data in the leaf nodes only .
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What is the difference between char s[] and char *s?
In C, one can use a string literal in a declaration like this:
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Is there a performance difference between i++ and ++i in C?
Is there a performance difference between i++ and ++i if the resulting value is not used?
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“x not in y” or “not x in y”
When testing for membership, we can use:
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Python 3 turn range to a list
I'm trying to make a list with numbers 1-1000 in it. Obviously this would be annoying to write/read, so I'm attempting to make a list with a range in it. In Python 2 it seems that:
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How do I get current date/time on the Windows command line in a suitable format for usage in a file/
... that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date . See @npocmaka's https://stackoverflow.com/a/19799236/8479
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Should enums in C# have their own file? [closed]
I have a class which uses an enumeration, the enum is currently in its own file which seems wasteful.
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