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What are naming conventions for MongoDB?
Is there a set of preferred naming conventions for MongoDB entitites such as databases, collections, field names?
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What is a word boundary in regex?
I am using Java regexes in Java 1.6 (to parse numeric output, among other purposes) and cannot find a precise definition of \b ("word boundary"). I had assumed that -12 would be an "integer word" (matched by \b\-?\d+\b ) but it appears that this does not work. I'd be grateful to know of ways ...
How to get the first line of a file in a bash script?
...t in a bash variable the first line of a file. I guess it is with the grep command, but it is any way to restrict the number of lines?
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MySQL - why not index every field?
Recently I've learned the wonder of indexes, and performance has improved dramatically. However, with all I've learned, I can't seem to find the answer to this question.
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Is there a generator version of `string.split()` in Python?
string.split() returns a list instance. Is there a version that returns a generator instead? Are there any reasons against having a generator version?
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__lt__ instead of __cmp__
Python 2.x has two ways to overload comparison operators, __cmp__ or the "rich comparison operators" such as __lt__ . The rich comparison overloads are said to be preferred, but why is this so?
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MySQL JOIN the most recent row only?
I have a table customer that stores a customer_id, email and reference. There is an additional table customer_data that stores a historical record of the changes made to the customer, i.e. when there's a change made a new row is inserted.
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In Python, how do I index a list with another list?
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How to group dataframe rows into list in pandas groupby?
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Django filter queryset __in for *every* item in list
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