COMMIT




i)                  Commit:
This command is used for save the transactions explicitly from the moment by user logon to the database to till execute this command.
Syntax:
Commit;
EX:
SQL>commit;
Commit complete.

consider the emp table having the following records.
SQL>select * from emp;
EMPNO
ENAME
JOB
MGR
HIREDATE
SAL
COMM
DEPTNO
7369
SMITH
CLERK
7902
17-Dec-80
800

20
7499
ALLEN
SALESMAN
7698
20-Feb-81
1600
300
30
7521
WARD
SALESMAN
7698
22-Feb-81
1250
500
30
7566
JONES
MANAGER
7839
2-Apr-81
2975

20
7654
MARTIN
SALESMAN
7698
28-Sep-81
1250
1400
30
7698
BLAKE
MANAGER
7839
1-May-81
2850

30
7782
CLARK
MANAGER
7839
9-Jun-81
2450

10
7788
SCOTT
ANALYST
7566
9-Dec-82
3000

20
7839
KING
PRESIDENT

17-Nov-81
5000

10
7844
TURNER
SALESMAN
7698
8-Sep-81
1500

30
7876
ADAMS
CLERK
7788
12-Jan-83
1100

20
7900
JAMES
CLERK
7698
3-Dec-81
950

30

14 rows selected.

Following is the example which would delete records from the table having salary less then 1500, and commit the changes in the database.
SQL>delete from emp where sal<1500;
2 rows deleted.
SQL>commit;

As a result, two rows from the table would be deleted and select statement would produce the following result.
SQL>select * from emp;
EMPNO
ENAME
JOB
MGR
HIREDATE
SAL
COMM
DEPTNO
7369
SMITH
CLERK
7902
17-Dec-80
3000

20
7499
ALLEN
SALESMAN
7698
20-Feb-81
1600
300
30
7566
JONES
MANAGER
7839
2-Apr-81
2975

20
7698
BLAKE
MANAGER
7839
1-May-81
2850

30
7782
CLARK
MANAGER
7839
9-Jun-81
2450

10
7788
SCOTT
ANALYST
7566
9-Dec-82
3000

20
7839
KING
PRESIDENT

17-Nov-81
5000

10
7844
TURNER
SALESMAN
7698
8-Sep-81
1500

30
7876
ADAMS
CLERK
7788
12-Jan-83
3000

20
7900
JAMES
CLERK
7698
3-Dec-81
3000

30
7902
FORD
ANALYST
7566
3-Dec-81


20
7934
MILLER
CLERK
7782
23-Jan-82
3000

10

12 rows selected.


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