ensure new connection for each test sql

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📝 Summary

Supersedes #9352 by ensuring each test runs in a duckdb connection that closes automatically.

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✅ Merge Checklist

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• Tests have been added for the changes made.

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Summary by cubic

Use a fresh in-memory duckdb connection per test to isolate state and prevent flaky SQL error-handling tests. Tests now pass engine=duckdb_conn and call duckdb_conn.sql(...), so connections close automatically after each test.

• Bug Fixes
  • Add pytest fixture duckdb_conn that creates duckdb.connect(':memory:') and closes it after each test.
  • Replace implicit engine/global duckdb.sql(...) with explicit engine=duckdb_conn and duckdb_conn.sql(...).
  • Stabilizes tests for missing tables/columns, syntax errors, hints, and long-statement truncation.

^{Written for commit 359e017. Summary will update on new commits.}

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Project	Deployment	Actions	Updated (UTC)
marimo-docs	Ready	Preview, Comment	Apr 24, 2026 4:53am

[cubic-dev-ai]

No issues found across 1 file

[Copilot]

Pull request overview

This PR updates the DuckDB SQL error-handling tests to ensure each test runs against its own in-memory DuckDB connection, preventing cross-test table leakage and improving test isolation (superseding #9352’s table-cleanup approach).

Changes:

• Add a per-test duckdb_conn fixture that creates/closes an isolated in-memory DuckDB connection.
• Update DuckDB-related tests to use engine=duckdb_conn (and duckdb_conn.sql(...)) instead of the process-wide default connection.

[akshayka]

Thank you, much nicer :)