15.00 - Dropping Methods From a UDT - Teradata Database

Teradata Database SQL Data Definition Language Detailed Topics

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

Dropping Methods From a UDT

This clause is used to drop a method signature associated with the specified UDT from the definition of that UDT. This is the only way you can drop a method. There is no DROP METHOD statement.

If you do not specify a method type, the default type is INSTANCE.

You cannot drop observer or mutator methods from a UDT definition.

When you drop a method signature from a UDT definition, the system also destroys its associated external routines.

The method to be dropped must not be referenced by any of the following database definitions.

  • A cast.
  • See “CREATE CAST/ REPLACE CAST” on page 212.

  • An ordering.
  • See “CREATE ORDERING/ REPLACE ORDERING” on page 416.

  • A transform set.
  • See “CREATE TRANSFORM/ REPLACE TRANSFORM” on page 694.

    You can drop methods from a UDT definition even if any of the following database objects references it.

  • Cast
  • Macro
  • Stored procedure
  • Trigger
  • View
  • However, when you attempt to execute any of the affected database objects, the system returns an error to the requestor.

    The ANSI SQL standard does not permit you to drop methods from a distinct UDT definition; however, you can drop methods from distinct UDTs as a Teradata extension to the ANSI SQL:2011 standard.

    To replace the external routine for a method, use the REPLACE METHOD statement (see “REPLACE METHOD” on page 845 and SQL Data Definition Language Syntax and Examples).