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What is the difference between partitioning and bucketing a table in Hive ?
...ten used for distributing load horizontally, this has performance benefit, and helps in organizing data in a logical fashion. Example: if we are dealing with a large employee table and often run queries with WHERE clauses that restrict the results to a particular country or department . For a faster...
what is the difference between ?:, ?! and ?= in regex?
I searched for the meaning of these expressions but couldn't understand the exact difference between them.
This is what they say:
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Git copy file preserving history [duplicate]
... confusing question in Git.
Lets say, I have a file dir1/A.txt committed and git preserves a history of commits
7 Answers...
difference between variables inside and outside of __init__()
...ss. They're shared by all instances.
Variables created inside __init__ (and all other method functions) and prefaced with self. belong to the object instance.
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How can you do anything useful without mutable state?
I've been reading a lot of stuff about functional programming lately, and I can understand most of it, but the one thing I just can't wrap my head around is stateless coding. It seems to me that simplifying programming by removing mutable state is like "simplifying" a car by removing the dashboard:...
Why do we use __init__ in Python classes?
I am having trouble understanding the Initialization of classes.
8 Answers
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Why does typeof NaN return 'number'?
...eration
which return NaN:
Operations with a NaN as at least one operand
Indeterminate forms
The divisions 0/0, ∞/∞, ∞/−∞, −∞/∞, and −∞/−∞
The multiplications 0×∞ and 0×−∞
The power 1^∞
The additions ∞ + (−∞), (−∞) + ∞ and e...
What is the official “preferred” way to install pip and virtualenv systemwide?
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If you can install the latest Python (2.7.9 and up) Pip is now bundled with it.
See: https://docs.python.org/2.7//installing/index.html
If not :
Update (from the release notes):
Beginning with v1.5.1, pip does not require setuptools prior to running get-pip.py. Ad...
What are the default access modifiers in C#?
...ult access modifier for classes, methods, members, constructors, delegates and interfaces?
9 Answers
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When is it right for a constructor to throw an exception?
...hat supports one-stage construction, where the object is fully initialized and usable after construction.
One-stage constructors should throw if they fail to fully initialize the object. If the object cannot be initialized, it must not be allowed to exist, so the constructor must throw.
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