[zvonand]

Changelog category (leave one):

• Bug Fix (user-visible misbehavior in an official stable release)

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

Treat LowCardinality(String) like String in empty-string comparison rewrite (#2565 by @ianton-ru).

CI/CD Options

Exclude tests:

• Fast test
• Integration Tests
• Stateless tests
• Stateful tests
• Performance tests
• All with ASAN
• All with TSAN
• All with MSAN
• All with UBSAN
• All with Coverage
• All with Aarch64
• All Regression
• Disable CI Cache

Regression jobs to run:

• Fast suites (mostly <1h)
• Aggregate Functions (2h)
• Alter (1.5h)
• Benchmark (30m)
• ClickHouse Keeper (1h)
• Iceberg (2h)
• LDAP (1h)
• Parquet (1.5h)
• RBAC (1.5h)
• SSL Server (1h)
• S3 (2h)
• S3 Export (2h)
• Swarms (30m)
• Tiered Storage (2h)

Cherry-picked from #2565.

---

A Distributed table can declare LowCardinality(String) over a plain String column. optimize_empty_string_comparisons then rewrote only the underlying schema, and object_storage_cluster failed with NOT_FOUND_COLUMN_IN_BLOCK.

Documentation entry for user-facing changes

...

[github-actions]

Workflow [PR], commit [4493cf9]

[zvonand]

Superseded by #2611 (pr_sources.existing_ports).