Structured Types and Inheritance in SQL Structured types (a.k.a.user-defined types)can be declared and used in SQL create type Name as (firstname varchar(20), lastname varchar(20)) final create type Address as (street varchar(20), city varchar(20). zipcode varchar(20)) not final 。 Note:final and not final indicate whether subtypes can be created Structured types can be used to create tables with composite attributes create table person name Name, address Address, dateOfBirth date) Dot notation used to reference components:name.firstname Database System Concepts-7th Edition 29.8 ©Silberscha乜，Korth and SudarshanDatabase System Concepts - 7 29.8 ©Silberschatz, Korth and Sudarshan th Edition Structured Types and Inheritance in SQL ▪ Structured types (a.k.a. user-defined types) can be declared and used in SQL create type Name as (firstname varchar(20), lastname varchar(20)) final create type Address as (street varchar(20), city varchar(20), zipcode varchar(20)) not final • Note: final and not final indicate whether subtypes can be created ▪ Structured types can be used to create tables with composite attributes create table person ( name Name, address Address, dateOfBirth date) ▪ Dot notation used to reference components: name.firstname