Join types

System requirements

Joins and lookups in workbooks and datasets must use sources from the same connection. 

Join types in Sigma

Lookup

A lookup returns all rows from the current data and all data from matching rows in the joined data. When more than one match exists for a single row in the current data, the lookup returns an asterisk (*), maintaining the number of rows in the current data.

Lookup functions like a VLOOKUP Excel function. For more information, see Lookup join.

Inner join

An inner join returns rows that contain matching data in the current and joined data. It omits rows that don't contain matching data.

For more information, see Inner join.

Left outer join

A left outer join returns all rows from the current data and all data from matching rows in the joined data. When more than one match exists for a single row in the current data, the join adds a row for each match in the joined data, which can result in an expanded row count.

For more information, see Left outer join.

R‍ight outer join

A right outer join returns all rows from the joined data and all data from matching rows in the current data. When more than one match exists for a single row in the joined data, the join retains all matching rows in the current data.

For more information, see Right outer join.

Full outer join

A full outer join returns all rows from the current data and all rows from the joined data, consolidating matching rows where applicable.

For more information, see Full outer join.