OPAL Join Verbs

Join verbs link multiple datasets together. They may generate more, fewer, or the same number of output rows as input rows, depending on the join condition and verb.

Verb

Description

exists

Return the rows from the default dataset that have a match anywhere in the query time window.

follow

Return the rows from the additional joined dataset that have a match anywhere in the query time window.

fulljoin

Temporal full join, adding new columns in the output dataset.

join

Temporal inner join, adding new columns in the output dataset.

leftjoin

Temporal left join, adding new columns in the output dataset.

lookup

Find matching rows in a Resource or Interval dataset, making new columns in the output dataset.

surrounding

Rows from the “right” dataset that fall within the specified frame of at least one row in the default dataset are unioned with the

union

Create a new dataset consisting of the rows from the main input and each of the arguments.

update_resource

Update the current resource by merging an event (or point) table with it.