The trim_expression argument must evaluate to a single byte that has a byte data type or single character that has a character data type.
TRIM operates on the following types of string_expression arguments:
- Character, except for CLOB
- Byte, except for BLOB
If a numeric expression is used as the string_expression argument, it is converted implicitly to CHARACTER type.
- UDTs that have implicit casts to any of the following predefined types:
To define an implicit cast for a UDT, use the CREATE CAST statement and specify the AS ASSIGNMENT clause.
Implicit type conversion of UDTs for system operators and functions, including TRIM, is a Teradata extension to the ANSI SQL standard.