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How do MySQL indexes work?
I am really interested in how MySQL indexes work, more specifically, how can they return the data requested without scanning the entire table?
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What do single quotes do in C++ when used on multiple characters?
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Why are arrays covariant but generics are invariant?
From Effective Java by Joshua Bloch,
9 Answers
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What does “#define _GNU_SOURCE” imply?
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When I catch an exception, how do I get the type, file, and line number?
Catching an exception that would print like this:
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What's the difference between == and .equals in Scala?
What is the difference between == and .equals() in Scala, and when to use which?
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In C#, how do I calculate someone's age based on a DateTime type birthday?
A given DateTime Type represents a person's birthday.
How could I calculate his / her age in years?
61 Answers
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Difference between numpy.array shape (R, 1) and (R,)
... of the operations return in shape (R, 1) but some return (R,) . This will make matrix multiplication more tedious since explicit reshape is required. For example, given a matrix M , if we want to do numpy.dot(M[:,0], numpy.ones((1, R))) where R is the number of rows (of course, the same i...
Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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Header files for x86 SIMD intrinsics
Which header files provide the intrinsics for the different x86 SIMD instruction set extensions (MMX, SSE, AVX, ...)? It seems impossible to find such a list online. Correct me if I'm wrong.
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