Trigger on a view with user-defined types : Trigger on a view « Trigger « Oracle PL/SQL Tutorial






SQL>
SQL>
SQL> CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
  2                    ENAME VARCHAR2(10),
  3                    JOB VARCHAR2(9),
  4                    MGR NUMBER(4),
  5                    HIREDATE DATE,
  6                    SAL NUMBER(7, 2),
  7                    COMM NUMBER(7, 2),
  8                    DEPTNO NUMBER(2));

Table created.

SQL>
SQL>
SQL> INSERT INTO EMP VALUES (7369, 'SMITH', 'CLERK',    7902, TO_DATE('17-DEC-1980', 'DD-MON-YYYY'), 800, NULL, 20);

1 row created.

SQL> INSERT INTO EMP VALUES (7499, 'ALLEN', 'SALESMAN', 7698, TO_DATE('20-FEB-1981', 'DD-MON-YYYY'), 1600, 300, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7521, 'WARD',  'SALESMAN', 7698, TO_DATE('22-FEB-1981', 'DD-MON-YYYY'), 1250, 500, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7566, 'JONES', 'MANAGER',  7839, TO_DATE('2-APR-1981',  'DD-MON-YYYY'), 2975, NULL, 20);

1 row created.

SQL> INSERT INTO EMP VALUES (7654, 'MARTIN', 'SALESMAN', 7698,TO_DATE('28-SEP-1981', 'DD-MON-YYYY'), 1250, 1400, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7698, 'BLAKE', 'MANAGER', 7839,TO_DATE('1-MAY-1981', 'DD-MON-YYYY'), 2850, NULL, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7782, 'CLARK', 'MANAGER', 7839,TO_DATE('9-JUN-1981', 'DD-MON-YYYY'), 2450, NULL, 10);

1 row created.

SQL> INSERT INTO EMP VALUES (7788, 'SCOTT', 'ANALYST', 7566,TO_DATE('09-DEC-1982', 'DD-MON-YYYY'), 3000, NULL, 20);

1 row created.

SQL> INSERT INTO EMP VALUES (7839, 'KING', 'PRESIDENT', NULL,TO_DATE('17-NOV-1981', 'DD-MON-YYYY'), 5000, NULL, 10);

1 row created.

SQL> INSERT INTO EMP VALUES (7844, 'TURNER', 'SALESMAN', 7698,TO_DATE('8-SEP-1981', 'DD-MON-YYYY'), 1500, 0, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7876, 'ADAMS', 'CLERK', 7788,TO_DATE('12-JAN-1983', 'DD-MON-YYYY'), 1100, NULL, 20);

1 row created.

SQL> INSERT INTO EMP VALUES (7900, 'JAMES', 'CLERK', 7698,TO_DATE('3-DEC-1981', 'DD-MON-YYYY'), 950, NULL, 30);

1 row created.

SQL> INSERT INTO EMP VALUES (7902, 'FORD', 'ANALYST', 7566,TO_DATE('3-DEC-1981', 'DD-MON-YYYY'), 3000, NULL, 20);

1 row created.

SQL> INSERT INTO EMP VALUES (7934, 'MILLER', 'CLERK', 7782,TO_DATE('23-JAN-1982', 'DD-MON-YYYY'), 1300, NULL, 10);

1 row created.

SQL>
SQL>
SQL>
SQL>
SQL> CREATE TABLE DEPT (DEPTNO NUMBER(2),DNAME VARCHAR2(14),LOC VARCHAR2(13) );

Table created.

SQL>
SQL> INSERT INTO DEPT VALUES (10, 'ACCOUNTING', 'NEW YORK');

1 row created.

SQL> INSERT INTO DEPT VALUES (20, 'RESEARCH', 'DALLAS');

1 row created.

SQL> INSERT INTO DEPT VALUES (30, 'SALES', 'CHICAGO');

1 row created.

SQL> INSERT INTO DEPT VALUES (40, 'OPERATIONS', 'BOSTON');

1 row created.

SQL>
SQL> create or replace type emp_type
  2  as object
  3  (empno       number(4),
  4   ename       varchar2(10),
  5   job         varchar2(9),
  6   mgr         number(4),
  7   hiredate    date,
  8   sal         number(7, 2),
  9   comm        number(7, 2)
 10  );
 11  /

Type created.

SQL>
SQL>
SQL> create or replace type emp_tab_type
  2  as table of emp_type
  3  /

Type created.

SQL>
SQL>
SQL> create or replace type dept_type
  2  as object
  3  ( deptno number(2),
  4    dname  varchar2(14),
  5    loc    varchar2(13),
  6    emps   emp_tab_type
  7  )
  8  /

Type created.

SQL>
SQL> create or replace view dept_or
  2  of dept_type
  3  with object identifier(deptno)
  4  as
  5  select deptno, dname, loc,
  6         cast ( multiset (
  7                 select empno, ename, job, mgr, hiredate, sal, comm
  8                   from emp
  9                  where emp.deptno = dept.deptno )
 10                as emp_tab_type )
 11    from dept
 12  /

View created.

SQL>
SQL> create or replace trigger EMPS_IO_UPDATE
  2  instead of UPDATE on nested table emps of dept_or
  3  begin
  4      if ( :new.empno = :old.empno )
  5      then
  6          update emp
  7             set ename = :new.ename, job = :new.job, mgr = :new.mgr,
  8              hiredate = :new.hiredate, sal = :new.sal, comm = :new.comm
  9           where empno = :old.empno;
 10      else
 11          raise_application_error(-20001,'Empno cannot be updated' );
 12      end if;
 13  end;
 14  /

Trigger created.

SQL>
SQL> update TABLE ( select p.emps
  2                   from dept_or p
  3                  where deptno = 20 )
  4     set ename = lower(ename)
  5  /

5 rows updated.

SQL>
SQL> select ename from emp where deptno = 20;


ENAME
----------
smith
jones
scott
adams
ford

SQL> select ename
  2    from TABLE( select p.emps
  3                  from dept_or p
  4                 where deptno = 20 );


ENAME
----------
smith
jones
scott
adams
ford

SQL>
SQL> drop type dept_type;

Type dropped.

SQL>
SQL> drop type emp_tab_type;

Type dropped.

SQL>
SQL> drop type emp_type;

Type dropped.

SQL>
SQL> drop table emp;

Table dropped.

SQL>
SQL> drop table dept;

Table dropped.








28.10.Trigger on a view
28.10.1.Trigger on a view
28.10.2.INSTEAD OF triggers
28.10.3.using the UPDATING ('column_name') clause
28.10.4.ORA-01733: virtual column not allowed here
28.10.5.Trigger on a view with user-defined types