CONSTRAINTS 
Definition
The system table CONSTRAINTS contains the CONSTRAINT definitions for all the tables for which the current user has privileges.
Structure
CONSTRAINTS
SCHEMANAME |
CHAR(32) |
Name of the schema of the table |
OWNER |
CHAR(32) |
Name of the owner of the table |
TABLENAME |
CHAR(32) |
Name of table with the CONSTRAINT definition |
CONSTRAINTNAME |
CHAR(32) |
Name of the CONSTRAINT definition |
DEFINITION |
LONG |
Text of the CONSTRAINT definition |
See also:
Evaluating System Tables, CONSTRAINTS
SQL Reference Manual, CONSTRAINT Definition (constraint_definition)