AggregationIterator — Generic Iterator of UnsafeRows for Aggregate Physical Operators
Iterators are data structures that allow to iterate over a sequence of elements. They have a
hasNext
method for checking if there is a next element available, and anext
method which returns the next element and discards it from the iterator.
Note
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AggregationIterator is a Scala abstract class.
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Used exclusively when |
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Used exclusively when |
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Used exclusively when
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Name | Description |
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Used when…FIXME |
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ImperativeAggregate functions Used when…FIXME |
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Positions Used when…FIXME |
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Used when…FIXME |
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Used when…FIXME |
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Grouping attributes Used when…FIXME |
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Used when…FIXME |
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Used when…FIXME |
Creating AggregationIterator Instance
AggregationIterator
takes the following when created:
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Grouping named expressions
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Input attributes
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Aggregate attributes
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Result named expressions
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Function to create a new
MutableProjection
given expressions and attributes
AggregationIterator
initializes the internal registries and counters.
initializeAggregateFunctions
Caution
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FIXME |
generateProcessRow
Method
Caution
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FIXME |