The experiment tells you the misleading usage of or and between in the where condition (refuse to repost, which is mandatory for violators)

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 02-apr-81 2975 20
7654 Martin salesman 7698 28-sep-81 1250 1400 30
7698 Blake manager 7839 01-may-81 2850 30
7782 Clark manager 7839 09-jun-81 2450 10
7788 Scott analyst 7566 19-apr-87 3000 20
7839 King President 17-nov-81 5000 10
7844 Turner salesman 7698 08-sep-81 1500 0 30
7876 Adams clerk 7788 23-may-87 1100 20

Empno ename job Mgr hiredate Sal comm deptno
------------------------------------------------------------------------------
7900 James Clerk 7698 03-dec-81 950 30
7902 Ford analyst 7566 03-dec-81 3000 20
7934 Miller clerk 7782 23-Jan-82 1300 10

14 rows selected.

SQL> select * from EMP where ename between 'a 'and 'C ';

Empno ename job Mgr hiredate Sal comm deptno
------------------------------------------------------------------------------
7499 Allen salesman 7698 20-feb-81 1600 300 30
7698 Blake manager 7839 01-may-81 2850 30
7876 Adams clerk 7788 23-may-87 1100 20

SQL> select * from EMP where ename like 'a % 'or ename like' B % 'or ename like 'C % ';

Empno ename job Mgr hiredate Sal comm deptno
------------------------------------------------------------------------------
7499 Allen salesman 7698 20-feb-81 1600 300 30
7698 Blake manager 7839 01-may-81 2850 30
7782 Clark manager 7839 09-jun-81 2450 10

7876 Adams clerk 7788 23-may-87 1100 20

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