- CREATE CAST (see CREATE CAST and REPLACE CAST).
Also see Default Cast For a Structured UDT.
- CREATE ORDERING (see CREATE ORDERING and REPLACE ORDERING).
Also see Default Ordering For a Structured UDT.
If you are creating a structured UDT that might be used for a hash index definition, you must ensure that its ordering function never returns a null. If it does, Teradata Database aborts the request and returns an error to the requestor.
- CREATE TRANSFORM (see CREATE TRANSFORM and REPLACE TRANSFORM).
You must create explicit ordering and transform functionality for all structured UDTs that you create. If you attempt to specify a structured UDT as the data type for any column of any table, but you have not created ordering and transform functionality for that UDT, the system returns an error to the requestor.
You are not required to create explicit casting functionality for a structured UDT; however, you must create a cast if the structured UDT is to perform in certain SQL expressions such as the USING modifier, or to participate in various loading operations such as Fastload and MultiLoad.
Enabling Full Functionality For a Structured UDT summarizes the implications for structured UDTs of this and the topics that follow by explaining which functionalities must be explicitly user-defined before a newly created structured UDT can be used as the type of a column table.