-- https://docs.oracle.com/en/database/oracle/oracle-database/23/lnpls/plsql-triggers.html
CREATE OR REPLACE TYPE Book_t AS OBJECT (
  Booknum    NUMBER,
  Title      VARCHAR2(20),
  Author     VARCHAR2(20),
  Available  CHAR(1)
);
/
CREATE OR REPLACE TYPE Book_list_t AS TABLE OF Book_t;
/