chore(ibis-server): use LEFT JOIN for table_comments in Trino metadata to avoid missing tables

[okayhooni]

Problem

Tables missing from the Trino metadata listing when system.metadata.table_comments has no entry for a given catalog.

This commonly occurs with Trino's catalog redirection (e.g., Hive → Iceberg migration): information_schema.tables/columns correctly resolve the redirected table under the target catalog, but system.metadata.table_comments retains the entry only under the original catalog. The INNER JOIN causes these tables to silently disappear from the list.

Fix

Change INNER JOIN system.metadata.table_comments → LEFT JOIN so that tables without a comment entry are still returned (with NULL description).

Summary by CodeRabbit

Bug Fixes

• Improved Trino data type support with correct mappings for timestamp variants, time types, and intervals, reducing type-related errors when querying and displaying data.
• Enhanced table metadata retrieval to display all tables, including those without explicit comments, so metadata views now show tables even when comment entries are missing.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 012e7c40-d456-45d3-8adc-17c78789fbec

📥 Commits

Reviewing files that changed from the base of the PR and between 2c5b71c and 04dae23.

📒 Files selected for processing (1)

• ibis-server/app/model/metadata/trino.py

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📝 Walkthrough

Walkthrough

Changed the SQL join in Trino metadata query from INNER JOIN to LEFT JOIN in get_table_list so table rows are returned even when there is no matching row in system.metadata.table_comments.

Changes

Cohort / File(s)	Summary
Trino metadata query ibis-server/app/model/metadata/trino.py	Replaced INNER JOIN with LEFT JOIN for system.metadata.table_comments in get_table_list, allowing tables without comments to appear in results.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Possibly related PRs

• fix(ibis-server): fix Trino timestamp type mapping for timestamp with time zone #1442: Similar Trino metadata/type mapping changes referenced in other work
• chore(ibis): refactor the type mapping table #1302: Related Trino mapping adjustments

Suggested labels

ibis, python

Suggested reviewers

• goldmedal
• douenergy

Poem

🐰 I hopped through joins both near and long,
Switched to LEFT to right a small wrong,
Now tables appear, though comments are few,
A little hop, and the view feels new. 🌿

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: replacing INNER JOIN with LEFT JOIN for table_comments to prevent tables without comment entries from being excluded.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@ibis-server/app/model/metadata/trino.py`:
- Line 52: The current exact lookup for interval types in _transform_column_type
misses Trino's qualified names like "interval day to second" or "interval year
to month"; update the logic in _transform_column_type to normalize the input
(lowercase, strip any trailing "(...)" already handled) and then either add
explicit keys for Trino spellings (e.g., "interval day to second", "interval
year to month") to the mapping that includes RustWrenEngineColumnType.INTERVAL,
or change the lookup to a prefix match: if
normalized_type.startswith("interval") return RustWrenEngineColumnType.INTERVAL;
keep the existing exact-match fallback for other types.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 82326c63-f65d-4c3a-b95d-444deb1ab40f

📥 Commits

Reviewing files that changed from the base of the PR and between fc1c54b and 2c5b71c.

📒 Files selected for processing (1)

• ibis-server/app/model/metadata/trino.py

[goldmedal]

Thanks @okayhooni 👍