ASA SQL User's Guide
Ensuring Data Integrity
Enforcing entity and referential integrity
Your database can lose referential integrity if someone:
updates or deletes a primary key value. All the foreign keys referencing that primary key would become invalid.
adds a new row to the foreign table, and enters a value for the foreign key that has no corresponding primary key value. The database would become invalid.
Adaptive Server Anywhere provides protection against both types of integrity loss.