Arithmetic and text operator functions for opaque data types

The database server provides operator functions for arithmetic operators (see Arithmetic operators) and text operators (see Text operators). The operator functions that the database server provides handle the built-in data types. You can overload an operator function to provide the associated operation on your new opaque data type.

If you overload an operator function, make sure you follow these rules:
  1. The name of the operator function must match the name of one of the functions that the database server provides. The name is not case sensitive; the plus() function is the same as the Plus() function.
  2. The operator function must handle the correct number of parameters.
  3. The operator function must return the correct data type, where appropriate.