Write a trigger that check the student_id must be start with ‘M’. PL/SQL trigger that check the student_id must be start with ‘M’

Write a trigger that check the student_id must be start with ‘M’. PL/SQL trigger that check the student_id must be start with ‘M’

create table student_id(sno varchar2(10));

insert into student_id values(‘&sno’)

SQL> select * from student_id;


SNO

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set serveroutput on

create or replace trigger tri30 before insert on student_id for each row

declare

tsno student_id.sno%type;

begin

tsno:=:new.sno;

dbms_output.put_line(tsno);

if tsno not like 'M%' then

raise_application_error(-20005,'Invalid Number');

end if;

end;