Use rollback in PL/SQL : Rollback Commit « PL SQL Statements « Oracle PL/SQL Tutorial






SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE),
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /

Table created.

SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ('01','Jason',    'Martin',  to_date('19960725','YYYYMMDD'), to_date('20060725','YYYYMMDD'), 1234.56, 'Toronto',  'Programmer')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values('02','Alison',   'Mathews', to_date('19760321','YYYYMMDD'), to_date('19860221','YYYYMMDD'), 6661.78, 'Vancouver','Tester')
  3  /

1 row created.

SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /


ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester

SQL>
SQL>
SQL>
SQL> DECLARE
  2     v_count NUMBER(10) := 0;
  3
  4  BEGIN
  5
  6     SELECT count(1)
  7     INTO v_count
  8     FROM employee
  9     WHERE id = 5;
 10
 11     IF v_count = 0
 12     THEN
 13        INSERT INTO employee (id, first_name, last_name)
 14        VALUES (5, 'Randy', 'Stauf');
 15     END IF;
 16     ROLLBACK;
 17  EXCEPTION
 18     WHEN OTHERS
 19     THEN
 20        DBMS_OUTPUT.PUT_LINE(SQLERRM);
 21  END;
 22  /

PL/SQL procedure successfully completed.

SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /

Table dropped.








22.13.Rollback Commit
22.13.1.Adding a Partial Rollback
22.13.2.Use rollback in PL/SQL
22.13.3.Roll back in exception handler
22.13.4.Implicit commits
22.13.5.A Full, Explicit Rollback
22.13.6.Firing explicit and implicit commits