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Difference between Document-based and Key/Value-based databases?
I know there are three different, popular types of non-sql databases.
2 Answers
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Find the most common element in a list
...e highest frequency item (for just 1 item, that's O(N) time). As Counter() now is heavily optimised (counting takes place in a C loop), it can easily beat this solution even for small lists. It blows it out of the water for large lists.
– Martijn Pieters♦
Oct...
What's the best way to check if a file exists in C?
... == EEXIST) {
/* the file already existed */
...
}
} else {
/* now you can use the file */
}
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Is there any difference between GROUP BY and DISTINCT
...s.
For example, if you have a bunch of purchase records, and you want to know how much was spent by each department, you might do something like:
SELECT department, SUM(amount) FROM purchases GROUP BY department
This will give you one row per department, containing the department name and the su...
Connect Java to a MySQL database
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Hi @SeanOwen I wonder that, why do we close rs and stmt? Why not just conn?
– Kamuran Sönecek
Apr 14 '16 at 6:37
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How to use a WSDL
...nce in VS won't work. However, the provider does want YOU (I mean OP) to know all you need to know about the service contract, that's why they sent the WSDL file. Now the OP needs to generate the proxy code from it, the question is how.
– azheglov
Aug 19 '09 ...
Convert HTML to NSAttributedString in iOS
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Andrew. This is working fine. I wanted to know what all short of events that i have to handle in my UITextView if i will go with this approach. Can it handle Calendar event , Call, Email, Website link etc available in HTML? I hope UITextView is able to handle events c...
What are the differences between .gitignore and .gitkeep?
... do a touch /path/to/emptydirectory/.gitkeep to add the file, and Git will now be able to maintain this directory in the repository.
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When should I use @classmethod and when def method(self)?
...e one: I like the answer being split up into how - why. As far as i got it now @classmethod allows to access the function without the need for an instance. This is exactly what i was looking for, thank you.
– marue
May 14 '12 at 16:04
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How to trace the path in a Breadth-First Search?
...this seems much cleaner. Would it be possible to make a graph if you only know the start and the end but none of the nodes in-between? Or even another approach besides graphs?
– Christopher Markieta
Jan 19 '12 at 7:19
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