If Redshift kills an idle session, your next query will fail with an error (usually OperationalError or InterfaceError). The clean way to handle this in SQLAlchemy is to enable pool\_pre\_ping=True, which sends a quick SELECT 1 before using a connection and swaps out dead ones automatically. Pair that with pool\_recycle set to less than the idle timeout (e.g., 300 seconds for a 10-minute timeout) to proactively refresh connections before they expire. Keep sessions short-lived and add retry logic for critical queries. One gotcha: if a connection dies mid-transaction, you'll still get an error since transactions can't transparently recover - you'll need to rollback and retry. In short: pool\_pre\_ping handles dead connections, pool\_recycle prevents them from dying, and retries cover the edge cases.