Bidirectional Joins

Bidirectional joins are used in circumstances where the data between 2 joined tables needs to flow in both directions. In a unidirectional join, the data flows in a single direction from the primary table (the table containing the primary key column) to the foreign table (the table containing the foreign key column).

A bidirectional join is used to enable the data to flow in both directions: the data can then flow from the primary table to the foreign table, and from the foreign table to the primary table. This allows users to aggregate a dimension column by a measure. This is in contrast to a typical unidirectional join, where the measure is aggregated by the dimension.

Bidirectional joins are typically not needed, as the database tends to be built with the relationships in mind. Users should take care when adding bidirectional joins, as they affect the aggregation of measures in the query.

  • Click here to learn more about joins.
  • Click here to learn how to create and edit joins.

Create a Bidirectional Join

To create a bidirectional join, click the join and enable 'Bidirectional' from the properties: