Join

Pairs left and right events with equal keys whose lifetimes overlap; each pair lives for the overlap.

For every left event and right event with the same join key, if their lifetimes overlap, the output has one event whose lifetime is the intersection of the two, with a payload made by the result selector.

In the diagram, a:1 [1,5) and a:10 [2,4) overlap in [2,4); b:2 [3,9) and b:20 [4,7) overlap in [4,7). a:3 [6,8) has no overlapping a on the right, so it produces nothing. Drag a:30 left until it overlaps a:3 to see a third pair appear.

To join events that happen within some span of each other, first give the inputs that span as their lifetime with AlterEventDuration.

See also: LeftOuterJoin, WhereNotExists, AlterEventDuration