Write a sql statements for rollback commit and save points

CREATE TABLE mytr (url_id int, url_addr varchar(100), host_date date);

INSERT INTO mytr VALUES (1, 'www.google.com', '2012-10-01');

savepoint a;

INSERT INTO mytr VALUES (2, 'www.microsoft.com', '2012-10-12');

savepoint b;

INSERT INTO mytr VALUES (3, 'www.apple.com', '2012-10-17');

savepoint c;

INSERT INTO mytr VALUES (4, 'www.google.com', '2012-10-11');

savepoint d;

INSERT INTO mytr VALUES (5, 'www.cnn.com', '2012-10-21');

savepoint e;

INSERT INTO mytr VALUES (6, 'www.apple.com', '2012-10-30');

savepoint f;

rollback to c; //rollback upto savepoint c

commit; //whole transaction is committed and all savepoints are removed