4111
MariaDBERRORCommonMEDIUM confidence
Foreign key exists in an unrelated schema
Production Risk
High — Schema-level operations fail until cross-schema FKs are resolved.
Why it happens
- 1Cross-database foreign keys exist between schemas being modified.
- 2A DROP DATABASE was attempted while another database holds FKs referencing it.
Fix
Identify and drop cross-schema FKs before the operation
Identify and drop cross-schema FKs before the operation
SELECT TABLE_SCHEMA, TABLE_NAME, CONSTRAINT_NAME FROM information_schema.KEY_COLUMN_USAGE WHERE REFERENCED_TABLE_SCHEMA = 'target_schema';
Why this works
Lists all FK constraints that reference the target schema so they can be dropped first.
What not to do
✕
Sources
Official documentation ↗
MySQL 8.0 — 4111 ER_FOREIGN_KEY_EXISTS_IN_UNRELATED_SCHEMA
Content generated with AI assistance and reviewed for accuracy. Found an error? hello@errcodes.dev