Declaring parameters for procedures

Procedure parameters appear as a list in the CREATE PROCEDURE statement. Parameter names must conform to the rules for other database identifiers such as column names. They must have valid data types (see Chapter 3, “SQL Data Types,” in Reference: Building Blocks, Tables, and Procedures), and must be prefixed with one of the keywords IN, OUT or INOUT.

See ”Declaring parameters for procedures” in SQL Anywhere Server - SQL Usage.