Example: Variable Reference Table Function - Analytics Database - Teradata Vantage

SQL Data Definition Language Syntax and Examples

Deployment
VantageCloud
VantageCore
Edition
Enterprise
IntelliFlex
VMware
Product
Analytics Database
Teradata Vantage
Release Number
17.20
Published
June 2022
Language
English (United States)
Last Update
2024-10-04
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lifecycle
latest
Product Category
Teradata Vantage™

This example shows a variable reference table function equijoined to another table.

Note the following things about this example:
  • The table function is sent to all AMPs and is passed tbl.c1 from all rows in tbl1; therefore it is a variable mode table function (see Teradata Vantage™ - SQL External Routine Programming, B035-1147).
  • The designer of this table function added a third argument to demonstrate that the function can provide some intelligence by not producing any rows unless the condition “equal” is met. For example, if the input argument tbl_l.c1 and the row for value tf2.c1 are not equal, the function does not produce any rows. This code eliminates the need for a subsequent step to filter rows produced by the table function resulting from the WHERE clause condition.
           SELECT *
           FROM tbl_1, TABLE(tudf1(28.8, tbl_1.c1, 'equal')) AS tf2
           WHERE tbl_1.c1 = tf2.c1;