Redrive Restrictions - Advanced SQL Engine - Teradata Database

• Redrive only hides database restarts from requests running in the SQL partition.
• If a UDF or external stored procedure modifies data that is external to Vantage, then the request involving that function or procedure cannot be redriven.
• If a database restart occurs while SELECT AND CONSUME requests are waiting for rows to consume, the restart is hidden from the application, but the queued up requests will not be in the same order as they were at the time of the restart.
• If a PE node fails, then the restart cannot be hidden from applications that were logged onto the failing node.
• Database restarts cannot be hidden if the restart occurs:
  • During execution of stored procedures.
  • After the first request of an explicit Teradata transaction or an ANSI/ISO transaction and the transaction placed a write lock or exclusive lock on a table in database DBC.
  • After the request is committed on the AMPs but before the PE is notified of the commit.