uniqTheta functions¶
uniqTheta functions work for two uniqThetaSketch objects to do set operation calculations such as ∪ / ∩ / × (union/intersect/not), it is to return a new uniqThetaSketch object contain the result.
A uniqThetaSketch object is to be constructed by aggregation function uniqTheta with -State.
UniqThetaSketch is a data structure storage of approximate values set. For more information on RoaringBitmap, see: Theta Sketch Framework.
uniqThetaUnion¶
Two uniqThetaSketch objects to do union calculation(set operation ∪), the result is a new uniqThetaSketch.
uniqThetaUnion(uniqThetaSketch,uniqThetaSketch)
Arguments
uniqThetaSketch– uniqThetaSketch object.
Example
select finalizeAggregation(uniqThetaUnion(a, b)) as a_union_b, finalizeAggregation(a) as a_cardinality, finalizeAggregation(b) as b_cardinality
from
(select arrayReduce('uniqThetaState',[1,2]) as a, arrayReduce('uniqThetaState',[2,3,4]) as b )
┌─a_union_b─┬─a_cardinality─┬─b_cardinality─┐ │ 4 │ 2 │ 3 │ └───────────┴───────────────┴───────────────┘
uniqThetaIntersect¶
Two uniqThetaSketch objects to do intersect calculation(set operation ∩), the result is a new uniqThetaSketch.
uniqThetaIntersect(uniqThetaSketch,uniqThetaSketch)
Arguments
uniqThetaSketch– uniqThetaSketch object.
Example
select finalizeAggregation(uniqThetaIntersect(a, b)) as a_intersect_b, finalizeAggregation(a) as a_cardinality, finalizeAggregation(b) as b_cardinality
from
(select arrayReduce('uniqThetaState',[1,2]) as a, arrayReduce('uniqThetaState',[2,3,4]) as b )
┌─a_intersect_b─┬─a_cardinality─┬─b_cardinality─┐ │ 1 │ 2 │ 3 │ └───────────────┴───────────────┴───────────────┘
uniqThetaNot¶
Two uniqThetaSketch objects to do a_not_b calculation(set operation ×), the result is a new uniqThetaSketch.
uniqThetaNot(uniqThetaSketch,uniqThetaSketch)
Arguments
uniqThetaSketch– uniqThetaSketch object.
Example
select finalizeAggregation(uniqThetaNot(a, b)) as a_not_b, finalizeAggregation(a) as a_cardinality, finalizeAggregation(b) as b_cardinality
from
(select arrayReduce('uniqThetaState',[2,3,4]) as a, arrayReduce('uniqThetaState',[1,2]) as b )
┌─a_not_b─┬─a_cardinality─┬─b_cardinality─┐ │ 2 │ 3 │ 2 │ └─────────┴───────────────┴───────────────┘