Teradata

This section describes features specific to the Teradata family of databases.

• Transform Groups
  A transform is a mechanism for creating an external representation of the UDT that is used when exporting and importing data between the client and the Teradata server. This mechanism allows most Teradata client utilities and open APIs to transparently move data to and from a UDT without the need for special logic or metadata.
• Teradata Database Permissions
  You can define multiple databases in a PDM for Teradata, and also define permissions on the database object.
• Primary Indexes in Teradata
  In Teradata, users tend to use indexes rather than key constraints.
• Error Tables
  Teradata can record errors encounterd when writing to a data table in an error table associated with the data table. PowerDesigner models error tables as extended objects with a stereotype of <<ErrorTable>>.
• Join Indexes
  Join indexes are materialized views that improve access times for cross-table queries, and which are automatically updated when changed are made to the underlying tables. PowerDesigner models join indexes as views with a stereotype of <<JoinIndex>>.
• Hash Indexes
  Hash indexes are designed to improve query performance like join indexes, but may in addition enable you to avoid accessing the base table. PowerDesigner models hash indexes as extended objects with a stereotype of <<HashIndex>>.
• Teradata Extended Attributes
  The following extended attributes are defined by default in the Teradata DBMS.