flight_sql.rs:271-322 — race between execute and do_get

[thanos]

6. flight_sql.rs:271-322 — race between execute and do_get
   The client Mutex is released between the two RPC calls. Two concurrent queries on the same client could interleave internal state or metadata updates. If
   FlightSqlServiceClient has any mutable per-request state (auth token refresh, etc.), this is a bug. Worth verifying against arrow-flight docs or holding the lock for the
   full query path.