16.20 - Deterministic Characteristics Clause - 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)

This optional clause declares whether the function returns the same results for identical inputs or not.

Teradata Database supports two deterministic characteristics options:

  • DETERMINISTIC
  • NOT DETERMINISTIC

Teradata Database must evaluate each row selected by a non-deterministic UDF condition individually because the evaluation of the function can change for each row selected within a query (this qualification includes both specifying NOT DETERMINISTIC explicitly and not specifying DETERMINISTIC, because NOT DETERMINISTIC is the default option for the clause). A predicate that includes a non-deterministic UDF specified on an index results in an all-AMP operation in spite of the index having been specified in the predicate.