Primary Key Data Type PropagationThe data types are not propagated automatically when you change the parent attribute's (primary key) data type. DeZign for Databases can't do this because sometimes the user don't want that. DeZign for Databases will warn you when the data types in a relationship don't match. For ex. TINYINT-INT matches but INT-VARCHAR does not match.
When you create a relationship, DeZign for Databases propagates the parent attribute's (primary key) data type to the child attribute's (foreign key) data type. When the parent attribute's data type is an autonumber/autoincrement data type, the child attribute's data type becomes the data type specified in the data type definition.
See also: About Primary Keys and auto increment columns