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Can I have multiple primary keys in a single table?
Can I have multiple primary keys in a single table?
12 Answers
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How does database indexing work? [closed]
Given that indexing is so important as your data set increases in size, can someone explain how indexing works at a database-agnostic level?
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Difference between Covariance & Contra-variance
I am having trouble understanding the difference between covariance and contravariance.
5 Answers
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When do I use a dot, arrow, or double colon to refer to members of a class in C++?
Coming from other C-derived languages (like Java or C#) to C++, it is at first very confusing that C++ has three ways to refer to members of a class: a::b , a.b , and a->b . When do I use which one of these operators?
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What is a raw type and why shouldn't we use it?
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15 Answers
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What's the fastest way to loop through an array in JavaScript?
I learned from books that you should write for loop like this：
22 Answers
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Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
For example I have two dicts:
17 Answers
17
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Understanding REST: Verbs, error codes, and authentication
I am looking for a way to wrap APIs around default functions in my PHP-based web applications, databases and CMSs.
10 Answ...
How does password salt help against a rainbow table attack?
I'm having some trouble understanding the purpose of a salt to a password. It's my understanding that the primary use is to hamper a rainbow table attack. However, the methods I've seen to implement this don't seem to really make the problem harder.
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How to get a value from a cell of a dataframe?
I have constructed a condition that extract exactly one row from my data frame:
11 Answers
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