Returns a distinct or structured UDT data type.
ANSI Compliance
This statement is ANSI SQL:2011 compliant, but includes non-ANSI Teradata extensions.
The requirement that parentheses appear when the argument list is empty is a Teradata extension to preserve compatibility with existing applications.
Required Privileges
To use a UDT expression, you must have the UDTTYPE, UDTMETHOD, or UDTUSAGE on the SYSUDTLIB database or the UDTUSAGE privilege on all of the specified UDTs.
Syntax
{ [ database_name. ] table_name ] column_name |
udf_name ( [ argument_1 [,...] ] ) |
CAST ( expression AS udt_name ) |
[ NEW [SYSUDTLIB.] ] constructor_name ( [ argument_2 [,...] ] )
} [ . method_spec [. ...] ]
- method_spec
method_name ( [ argument_3 [,...] ] )
Syntax Elements
- database_name
- An optional qualifier for the column_name.
- table_name
- An optional qualifier for the column_name.
- column_name
The name of a distinct or structured UDT column.
Constructor methods have the same name as the UDT with which they are associated.
A qualifier for column_name.
- udf_name
The name of a distinct or structured UDT data type.
Constructor methods have the same name as the UDT with which they are associated.
- argument
An argument to the UDF.
An argument to pass to the constructor.
An argument to pass to the method.
Parentheses must appear even though the argument list may be empty.
- CAST
A CAST expression that converts a source data type to a distinct or structured UDT.
Data type conversions involving UDTs require appropriate cast definitions for the UDTs. To define a cast for a UDT, use the CREATE CAST statement. For more information on CREATE CAST, see Teradata Vantage™ - SQL Data Definition Language Syntax and Examples, B035-1144.
- expression
- An expression that results in a UDT data type.
- udt_name
The name of a distinct or structured UDT data type.
Constructor methods have the same name as the UDT with which they are associated.
- NEW
- An expression that constructs a new instance of a structured type and initializes it using the specified constructor method.
- SYSUDTLIB.
The database in which the constructor exists.
Vantage only searches the SYSUDTLIB database for UDT constructors, regardless of whether the database name appears in the expression.
- constructor_name
The name of a constructor method associated with a UDT.
Constructor methods have the same name as the UDT with which they are associated.
- method_name
- The name of an instance method that returns a UDT.