Fix Hive cleanup error: use DROP VIEW when check_timestamps fails

[Copilot]

Hive throws WRONG_COMMAND_FOR_OBJECT_TYPE when attempting DROP TABLE on a VIEW during cleanup after check_timestamps fails.

Root Cause

In apply_mapping, when output_file is None:

• Hive creates a VIEW via create_materialized_view (line 229-232)
• Other engines create a TABLE via create_table (line 234)

The exception handler unconditionally used DROP TABLE, which fails for Hive VIEWs.

Changes

src/chronify/time_series_mapper_base.py:149-152

Detect engine type and use appropriate DROP command:

if output_file is None:
    if engine.name == "hive":
        conn.execute(text(f"DROP VIEW {to_schema.name}"))
    else:
        conn.execute(text(f"DROP TABLE {to_schema.name}"))

Matches existing pattern in the finally block (line 156-157) and elsewhere in the codebase.

Original prompt

The CI job is failing on Hive when attempting to DROP TABLE on an object that is actually a VIEW, resulting in the error:

org.apache.hive.service.cli.HiveSQLException:Error running query: [WRONG_COMMAND_FOR_OBJECT_TYPE] ...is a VIEW. Use DROP VIEW instead. SQLSTATE: 42809

This occurs during cleanup when a mapped table or intermediate table needs to be dropped after check_timestamps fails. Specifically, in Hive SQL, 'DROP TABLE' only works on tables, not views. The code base currently issues DROP TABLE regardless of whether the object is a table or a view.

To fix:

• Detect if the object to be dropped is a VIEW or a TABLE when using Hive.
• Use 'DROP VIEW IF EXISTS ' for views, and 'DROP TABLE IF EXISTS ' for tables.
• This logic should be applied wherever such cleanup or rollback happens (likely in time_series_mapper_base or similar code used for mapping/cleanup after failures).
• Optionally, refactor common drop logic into a utility function.
• Add/adjust tests if needed to exercise both view and table dropping in Hive context.

References:

• Job failure: https://github.com/NatLabRockies/chronify/actions/runs/21301882873/job/61321315860?pr=61
• Main error: generators_pb_tz_converted is a VIEW. Use DROP VIEW instead. SQLSTATE: 42809
• Example log: check_timestamps failed on mapped table generators_pb_tz_converted. Drop it

This pull request was created from Copilot chat.

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