When are spatial indexes used?

Spatial indexes are used with queries that call functions to compare geometries. The Oracle and PostgreSQL ST_Geometry functions that use spatial indexes are the ones that test spatial relationships.


For information on DB2 ST_Geometry functions that can use a spatial index, see the DB2 documentation.

See the IBM Informix Spatial DataBlade Module User's Guide for information on functions that utilize Informix's R-tree spatial index.

Additionally, the spatial column must appear immediately after the spatial relationship function in the query for the spatial index to be used.