15.00 - Rules for Order Mapping UDFs - Teradata Database

Teradata Database SQL Data Definition Language Detailed Topics

prodname
Teradata Database
vrm_release
15.00
category
Programming Reference
featnum
B035-1184-015K

Rules for Order Mapping UDFs

If you specify a UDF as the MAP routine for an ordering, it must obey the following rules:

  • It must have one and only one parameter.
  • The data type of the single parameter you specify must be the same as that of the UDT specified as UDT_name.
  • The result data type must be a predefined data type.
  • Its predefined data type is valid except the following:

  • BLOB
  • CLOB
  • It must be declared to be DETERMINISTIC.
  • The name you specify for it in the ordering definition must be the name of a UDF contained within the SYSUDTLIB database.
  • See “CREATE FUNCTION (External Form)/ REPLACE FUNCTION (External Form)” on page 240 for details about UDF parameters, result data types, and the DETERMINISTIC option.