Standards have been developed by industry, government bodies, and the ISO for managing geometric objects in a relational database.

These standards include:
OpenGIS Consortium—Simple Features Specification for SQL
ISO19125-1, Geographic Information—Simple feature access,  Part 1: Common architecture
ISO19125-2, Geographic Information—Simple feature access, Part 2: SQL option
ISO 19107, Geographic information—Spatial schema
ISO 13249-3, Information technology Database languages SQL Multimedia and Application Packages, Part 3: Spatial.  

The DB2, Informix, Oracle, and PostgreSQL spatial type implementations are based on the OpenGIS and SQL/MM spatial type specifications. These implementations have been conformance tested by the OpenGIS (see www.opengis.org for further conformance information).

Consult Oracle documentation and www.opengis.org for Oracle Spatial conformance information.