Minimizing nested joins
Nested joins have been associated with longer-than-expected calculation times in the past. These joins often occur when pick-listed fields are used to restrict values based on a parent table.
Recommended approach
Instead of relying on drilling down to generate a nested join, it is often more efficient for the database to join directly to the target table. This approach reduces the load on the database and can improve calculation performance.
Exceptions
While nested joins can slow down calculations in other areas, there have been no reported performance issues when using nested joins on the time partition.