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Multiple Type Inheritance SQL:1999 and SQL:2003 do not support multiple inheritance If our type system supports multiple inheritance,we can define a type for teaching assistant as follows: create type Teaching Assistant under Student,Teacher To avoid a conflict between the two occurrences of department we can rename them create type Teaching Assistant under Student with (department as student dept ) Teacher with (department as teacherdept Each value must have a most-specific type Database System Concepts-6th Edition 22.13 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 22.13 ©Silberschatz, Korth and Sudarshan th Edition Multiple Type Inheritance SQL:1999 and SQL:2003 do not support multiple inheritance If our type system supports multiple inheritance, we can define a type for teaching assistant as follows: create type Teaching Assistant under Student, Teacher To avoid a conflict between the two occurrences of department we can rename them create type Teaching Assistant under Student with (department as student_dept ), Teacher with (department as teacher_dept ) Each value must have a most-specific type
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