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Difference between a theta join, equijoin and natural join
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A theta join allows for arbitrary comparison relationships (such as ≥).
An equijoin is a theta join using the equality operator.
A natural join is an equijoin on attributes that have the same name in each relationship.
Additionally,...
Convert all first letter to upper case, rest lower for each word
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Haha, really? That's where it is? I love .NET but some of the API designers are real jerks.
– George Mauer
Dec 21 '09 at 23:37
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How to implement __iter__(self) for a container object (Python)
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I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
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Why does Python use 'magic methods'?
...lable, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
7 Answers
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Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space
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I marked this answer correct after all these years, because i looked back and the accepted didn't exclude underscores
– Michael Randall
Apr 12 '18 at 11:23
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What integer hash function are good that accepts an integer hash key?
...mple) and has no common factors with it. This way the hash function covers all your hash space uniformly.
Edit: The biggest disadvantage of this hash function is that it preserves divisibility, so if your integers are all divisible by 2 or by 4 (which is not uncommon), their hashes will be too. Thi...
How to show all shared libraries used by executables in Linux?
...to know which libraries are used by executables on my system. More specifically, I'd like to rank which libraries are used the most, along with the binaries that use them. How can I do this?
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What is the difference between quiet NaN and signaling NaN?
...unit (FPU) or library if floating-point is implemented in software. A signalling NaN will produce a signal, usually in the form of exception from the FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and pr...
How to get a complete list of object's methods and attributes?
...butes, the short answer is: no. The problem is that the attributes are actually defined as the arguments accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir functi...
How to get number of entries in a Lua table?
...ual, any of 3, 5 and 9 are valid results for #t. According to the manual, calling # on non-sequences is undefined. That means that any result (-1, 3, 3.14, 5, 9) is valid.
– cubuspl42
May 12 '14 at 20:08
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