Antalya 26.3: Enabled experimental datalake catalogues by-default

[zvonand]

Changelog category (leave one):

• Improvement

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

Enabled experimental datalake catalogues by-default (#1504 by @Enmk).

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 #1504.

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Documentation entry for user-facing changes

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[github-actions]

Workflow [PR], commit [8a438d4]

[alsugiliazova]

Verification report: Altinity/ClickHouse PR #1743

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Conclusion

PR is merged. CI red on head, but every failure is either a pre-existing flake or a regression-suite scenario already broken at baseline on antalya-26.3. No PR-caused regression found. The diff is 9 lines of default-value flips for the allow_experimental_database_* settings — a configuration default change, no code path added.

Caveat — partial frontport (same as #1640 / #1646 / #1675 / #1687 / #1694 / #1723). Companion antalya-26.1 frontports are still missing on antalya-26.3; chronic regression failures here are branch-level missing-dependency symptoms. Iceberg sort key timezone continues to fail with the same UNRECOGNIZED_ARGUMENTS: '--iceberg_partition_timezone' from a binary that doesn't expose the option.

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CI on head 8a438d43 — failures

PR test workflow (1 failed check, 44 success)

Check	Test FAIL	Class
Integration tests (amd_asan, db disk, old analyzer, 4/6)	test_replicated_database::test_sync_replica	Pre-existing flake — 84 / 37 PRs / 90d

Regression workflow (10 failed checks)

Check	Top failing tests on PR-1743 builds (30d)	Baseline (antalya-26.3, 30d)	Class
Swarms (Release + Aarch64)	swarm joins / join clause, cluster discovery / multiple paths, node failure / network failure, node failure / cpu overload, swarm join sanity / join with clause (×2 each)	30–44% on every PR	Pre-existing broken
S3Export (partition) (Release + Aarch64)	sanity / no partition by (×2)	50%	Pre-existing broken
Iceberg (1) (Release + Aarch64)	rest catalog / sort key timezone / day transform utc (×2), rest catalog / iceberg iterator race condition (×2)	41% / 28%	Missing-dep + pre-existing flaky
Iceberg (2) (Release + Aarch64)	(chronic glue-catalog / swarm-examples / race-condition variants)	chronic	Pre-existing flaky
Parquet (Release + Aarch64)	postgresql/mysql round-trip compression-type variants (×2 each)	~36%	Pre-existing flaky

Regression DB on /PRs/1743/ builds (30d): 152 Fail / 5,358 OK ≈ 2.8%. Every top failure matches the all-PR baseline fail rate on antalya-26.3.

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Related to PR diff?

PR is a 9-line default-value flip — switches allow_experimental_database_iceberg / allow_experimental_database_glue_catalog / allow_experimental_database_unity_catalog etc. to true by default (2 files: settings declaration + settings-history). No code path is added or removed.

Failing test	Diff overlap	Related?
test_replicated_database::test_sync_replica	none (replication)	No
swarms / *, parquet / *, s3_export_partition / *	none — these suites do not toggle the data-lake-catalog defaults	No
iceberg / sort key timezone / *	none — failure is UNRECOGNIZED_ARGUMENTS (missing-dep), not the default-value flip	No
iceberg / iterator race condition (rest + glue)	unrelated to the default flip — failure rate matches baseline on PRs that don't change defaults	No

No failing test fails above the all-PR baseline or is sensitive to the default-value flip.

Side note: Enabling experimental datalake catalogues by default could in principle change behavior for users not opting in; that is a policy / release-notes question, not a CI-verification one — but worth flagging for the changelog.

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Recommendations

1. No action on this PR. Merged and effectively clean.
2. Surface the default change in release notes for antalya-26.3 — users will pick up Database = Iceberg, Database = Glue, Database = Unity etc. without setting allow_experimental_database_* explicitly. Not a CI gate, but a downstream-comms item.
3. Re-verify after the companion 26.1 → 26.3 frontports land — same list as the other 26.3 frontport reports.
4. Same chronic-baseline cleanup recommendation as VERIFICATION_PR_1640.md for swarms / parquet / s3_export_partition / iceberg scenarios.

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Local checkout

cd /Users/alsugilyazova/workspace/altinity-clickhouse/ClickHouse
gh pr checkout 1743 --repo Altinity/ClickHouse
# HEAD: 8a438d433708b26c1156d1b2aa2fee65bfd5136c

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Password held in shell env for this session; not persisted to disk.

[alsugiliazova]

Audit: PR #1743 — Antalya 26.3: Enabled experimental datalake catalogues by-default

AI audit note: This review comment was generated by AI (Cursor agent, audit-review skill).

Audit update for PR #1743 (experimental datalake catalog defaults)

Confirmed defects

No confirmed defects in reviewed scope.