PostgreSQLERROR 23503
PostgreSQL: Foreign Key Constraint Violation
PostgreSQL 23503 is raised when an INSERT or UPDATE references a value in a foreign key column that does not exist in the parent table, or when a DELETE would leave orphaned child rows.
Example Query
INSERT INTO orders (user_id) VALUES (9999); -- Fails if users table has no row with id=9999
Common Causes
- 1Inserting a child row before the parent row exists
- 2Deleting a parent row that still has dependent child rows
- 3Out-of-sync data between environments after a partial restore
How to Fix It
Insert parent records before child records. Use ON DELETE CASCADE or ON DELETE SET NULL on the constraint if child rows should be handled automatically. Temporarily disable triggers with SET session_replication_role = replica for bulk loads, then re-enable and validate.
Need a reliable database?
Try Supabase — free PostgreSQL with a generous free tier. No credit card required.
Got a query causing this error?
Paste it into SQLbuddy and get an instant plain-English explanation with optimization tips.
Analyze My Query →