class ConceptQL::Operators::Last
Represents a operator that will grab the last occurrence of something
The operator treats all streams as a single, large stream. It partitions that larget stream by person_id, then sorts within those groupings by start_date and then select at most one row per person, regardless of how many different types of streams enter the operator
If two rows have the same start_date, the order of their ranking is arbitrary
If we ask for the last occurrence of something and a person has no occurrences, this operator returns nothing for that person
Public Instance Methods
occurrence()
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# File lib/conceptql/operators/last.rb, line 22 def occurrence -1 end