update

backend/onyx/background/celery/tasks/connector_deletion/tasks.py

@@ -30,6 +30,9 @@ from onyx.db.connector_credential_pair import (
 )
 from onyx.db.connector_credential_pair import get_connector_credential_pair_from_id
 from onyx.db.connector_credential_pair import get_connector_credential_pairs
+from onyx.db.document import (
+    delete_all_documents_by_connector_credential_pair__no_commit,
+)
 from onyx.db.document import get_document_ids_for_connector_credential_pair
 from onyx.db.document_set import delete_document_set_cc_pair_relationship__no_commit
 from onyx.db.engine import get_session_with_current_tenant
@@ -440,6 +443,14 @@ def monitor_connector_deletion_taskset(
                 db_session=db_session,
             )
 
+            # Explicitly delete document by connector credential pair records before deleting the connector
+            # This is needed because connector_id is a primary key in that table and cascading deletes won't work
+            delete_all_documents_by_connector_credential_pair__no_commit(
+                db_session=db_session,
+                connector_id=cc_pair.connector_id,
+                credential_id=cc_pair.credential_id,
+            )
+
             # finally, delete the cc-pair
             delete_connector_credential_pair__no_commit(
                 db_session=db_session,

backend/onyx/db/document.py

@@ -555,6 +555,28 @@ def delete_documents_by_connector_credential_pair__no_commit(
     db_session.execute(stmt)
 
 
+def delete_all_documents_by_connector_credential_pair__no_commit(
+    db_session: Session,
+    connector_id: int,
+    credential_id: int,
+) -> None:
+    """Deletes all document by connector credential pair entries for a specific connector and credential.
+    This is primarily used during connector deletion to ensure all references are removed
+    before deleting the connector itself. This is crucial because connector_id is part of the
+    primary key in DocumentByConnectorCredentialPair, and attempting to delete the Connector
+    would otherwise try to set the foreign key to NULL, which fails for primary keys.
+
+    NOTE: Does not commit the transaction, this must be done by the caller.
+    """
+    stmt = delete(DocumentByConnectorCredentialPair).where(
+        and_(
+            DocumentByConnectorCredentialPair.connector_id == connector_id,
+            DocumentByConnectorCredentialPair.credential_id == credential_id,
+        )
+    )
+    db_session.execute(stmt)
+
+
 def delete_documents__no_commit(db_session: Session, document_ids: list[str]) -> None:
     db_session.execute(delete(DbDocument).where(DbDocument.id.in_(document_ids)))