16.20 - Macro Support for Large Objects - 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)

You can use BLOB and CLOB columns in macros as long as they do not violate the restrictions on large object use with SQL.

These restrictions are named in the following bulleted list:
  • You cannot create a base table with more than 32 LOB columns, nor can you alter a base table to have more than 32 LOB columns.
  • You can increase the maximum size of a LOB column up to the system limit, but you cannot decrease the maximum size of an existing LOB column.
  • LOB columns can only carry the following attributes:
    • NULL
    • NOT NULL
    • TITLE
    • FORMAT
  • LOB columns cannot be a component of any index.
  • A base table containing LOB columns must have at least one non-LOB column to act as its primary index.
  • The first column specified in a base table definition cannot be a LOB unless a uniqueness constraint is defined on some non-LOB column set in that table.
  • The uniqueness of a SET base table must be defined on the basis its non-LOB column set because LOB columns cannot be used to specify row uniqueness.
  • You cannot define integrity constraints on LOB columns, nor can you define integrity constraints that reference LOB columns.
  • LOB columns can be components of a view subject to the restrictions provided in this list and the semantics of view definitions.
  • LOB columns can be parameters of a user-defined function.

For more information, see Teradata Vantage™ Data Types and Literals, B035-1143.