release-26.1: sql: clean up FK back-references during rollback of CREATE TABLE#165994
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rafiss merged 2 commits intocockroachdb:release-26.1from Mar 17, 2026
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…DD state Previously, when a CREATE TABLE with inline FOREIGN KEY constraints had its schema change job fail permanently, rollbackSchemaChange() would mark the new table as Dropped and queue it for GC, but never remove the InboundFK entries that had been added to the referenced table(s) during the SQL transaction. This left orphaned FK back-references pointing to a descriptor that no longer exists, causing descriptor validation errors like: relation "parent" (209): invalid foreign key backreference: missing table=264: referenced descriptor not found The fix adds FK back-reference cleanup in the ADD-state rollback path of rollbackSchemaChange(), alongside the existing view dependency cleanup. For each outbound FK on the table being rolled back, we remove the corresponding InboundFK from the referenced table. Similarly, for any inbound FKs (other tables referencing this one), we remove the corresponding OutboundFK from the origin table. This reuses the existing removeFKBackReferenceFromTable() helper already used by dropTableImpl() and maybeReverseMutations(). Errors during cleanup are logged as warnings and skipped (best-effort), matching the pattern used by dropViewDeps(). Epic: None Release note (bug fix): Fixed a bug in the legacy schema changer where rolling back a CREATE TABLE with inline FOREIGN KEY constraints could leave orphaned FK back-references on the referenced table, causing descriptor validation errors. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add TestCreateTableFKRollbackCleansBackrefs which verifies that when a CREATE TABLE with an inline FOREIGN KEY constraint has its async schema change job fail, the rollback properly cleans up the InboundFK back-reference on the referenced table. The test: 1. Creates a parent table. 2. Creates a child table with an inline FK referencing the parent, while injecting a permanent error into the child's schema change job via the RunBeforeResume testing knob. 3. Waits for the schema change job to fail. 4. Verifies the child table no longer exists (rolled back from ADD state). 5. Waits for the GC job to fully delete the child descriptor, so that the validation error matches the production error exactly: "invalid foreign key backreference: missing table=N: referenced descriptor not found". 6. Asserts the parent does not appear in crdb_internal.invalid_objects. 7. Asserts the parent table has no orphaned InboundFKs. Closes cockroachdb#165551 Epic: None Release note: None Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Mar 17, 2026
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Backport 2/2 commits from #165551 on behalf of @spilchen.
Previously, when a CREATE TABLE with inline FOREIGN KEY constraints had its schema change job fail permanently, rollbackSchemaChange() would mark the new table as Dropped and queue it for GC, but never remove the InboundFK entries that had been added to the referenced table(s) during the SQL transaction. This left orphaned FK back-references pointing to a descriptor that no longer exists, causing descriptor validation errors like:
The fix adds FK back-reference cleanup in the ADD-state rollback path of rollbackSchemaChange(), alongside the existing view dependency cleanup. For each outbound FK on the table being rolled back, we remove the corresponding InboundFK from the referenced table. Similarly, for any inbound FKs (other tables referencing this one), we remove the corresponding OutboundFK from the origin table.
This reuses the existing removeFKBackReferenceFromTable() helper already used by dropTableImpl() and maybeReverseMutations(). Errors during cleanup are logged as warnings and skipped (best-effort), matching the pattern used by dropViewDeps().
Closes #165548
Epic: None
Release note (bug fix): Fixed a bug in the legacy schema changer where rolling back a CREATE TABLE with inline FOREIGN KEY constraints could leave orphaned FK back-references on the referenced table, causing descriptor validation errors.
Release justification: simple bug fix that has been hit a few times in support escalations