16.20 - PARAMETER STYLE - Teradata Database - Teradata Vantage NewSQL Engine

The parameter passing convention to be used when passing parameters to the table function.

The specified parameter style must match the parameter passing convention of the external function.

This clause is optional for SQL table functions and can only be specified once per function definition. It is mandatory for Java table functions.

If you do not specify a parameter style at this point, you can specify one with the external body reference.

You cannot specify parameter styles more than once in the same CREATE/REPLACE FUNCTION request.

You cannot use a table function to enforce row-level security for a security constraint.

For more information about UDF parameter styles, see “CREATE FUNCTION (Table Form)” in Teradata Vantage™ SQL Data Definition Language Detailed Topics , B035-1184 .

SQL

Uses indicator variables to pass arguments.

As a result, you can always pass nulls as inputs and return nulls in results.

SQL is the default parameter style.

JAVA

Mandatory for all Java table functions.

If the Java function must accept null arguments, then the EXTERNAL NAME clause must include the list of parameters and specify data types that map to Java objects.

SQLTABLE

Indicates the function is a table operator and is supported by all external languages. SQLTABLE models the input and output data as a row iterator over a collection of rows. A function defined with this parameter style can only accept TABLE as an input parameter type. For more information, see “Table Operators” in “C/C++ User-Defined Functions” and “Java User-Defined Functions” of Teradata Vantage™ SQL External Routine Programming , B035-1147 .