SQL> CREATE TABLE emp (
2 id NUMBER PRIMARY KEY,
3 fname VARCHAR2(50),
4 lname VARCHAR2(50)
5 );
Table created.
SQL>
SQL> INSERT INTO emp (id, fname, lname)VALUES (1, 'A', 'B');
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (2, 'C', 'D');
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (3, 'Enn', 'F');
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (4, 'G', 'H');
1 row created.
SQL> INSERT INTO emp (id, fname, lname)VALUES (5, 'G', 'Z');
1 row created.
SQL>
SQL>
SQL> ALTER SESSION SET SQL_TRACE = TRUE;
Session altered.
SQL> SELECT lname
2 FROM emp
3 WHERE fname = 'Mike';
no rows selected
SQL> ALTER SESSION SET SQL_TRACE = FALSE;
Session altered.
SQL>
SQL> drop table emp;
Table dropped.