16.20 - Reserved Redrive Query Band - Teradata Database - Teradata Vantage NewSQL Engine

Teradata Vantage™ SQL Data Definition Language Detailed Topics

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Release Date
March 2019
Content Type
Programming Reference
Publication ID
B035-1184-162K
Language
English (United States)
As a general rule, customer-written applications should not use the REDRIVE query band name. It is reserved for use by Teradata-written applications and applications written by third party Teradata partners.

The syntax for setting a Redrive query band is:

   SET QUERY_BAND = 'redrive=off;' FOR SESSION;
   SET QUERY_BAND = 'redrive=on;' FOR SESSION;

The Redrive capability is assigned to a session at logon time. Once a session is enabled with Redrive, you can use the Redrive query band to toggle Redrive protection on and off during the life of the session.

Redrive set to OFF disables Redrive protection for subsequent SQL requests in the session. When Redrive is off, there is no automatic Teradata Database recovery of submitted SQL requests after a database failure, and any recovery is controlled by the application.

Redrive set to ON enables Redrive protection for subsequent SQL requests in the session.

When subsequent query bands are processed, the previous query band is replaced completely unless the UPDATE option is specified in the SET QUERY_BAND statement. A session that wants to maintain a specific Redrive behavior must ensure that subsequent query bands include the desired Redrive attribute by specifying the Redrive name:value pair or using the UPDATE option to add to the existing query band. Redrive participation will return to the value specified in the RedriveDefaultParticipation DBS Control field if the Redrive attribute is omitted in subsequent query bands.
For details about Redrive functionality, see:
  • Teradata Vantage™ - Database Administration, B035-1093
  • The RedriveProtection and RedriveDefaultParticipation DBS Control fields in Teradata Vantage™ - Database Utilities , B035-1102