[rocksnow1942]

_get_table_filter_query() rendered () for an empty filter_names, so the get_multi_*() queries failed with 400 Syntax error: Unexpected ")". SQLAlchemy passes an empty filter_names when there's nothing to reflect, so these failed:

• MetaData().reflect(engine) on a database without tables
• MetaData.reflect() with only=[], or when all the tables are already in the MetaData
• Alembic >= 1.18 autogenerate on an empty database, since it pre-loads each schema with the get_multi_*() methods

This PR renders (FALSE) instead, so an empty filter_names returns no tables.

SQLAlchemy doesn't define what an empty filter_names means. Its built-in dialects check if filter_names:, so they treat [] like None and return all tables, while the IN UNNEST(@filter_names) filter of #18205 returns none. This PR returns none, which avoids reflecting the whole schema when there's nothing to load. I'm happy to switch to the other behavior if you prefer.

Tested with the unit and mockserver tests and the compliance suite against the emulator.

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Fixes #18838

[gemini-code-assist]

Code Review

This pull request fixes an issue where an empty filter_names argument in _get_table_filter_query would generate invalid SQL (()). The fix ensures that an empty filter renders a condition that is always false ((FALSE)), selecting no tables. Additionally, comprehensive unit and integration tests have been added to verify this behavior during metadata reflection and multi-column retrieval. There are no review comments, and I have no additional feedback to provide.