SQL> select address from address where upper(name) like 'JO%' AND (name like 'J%' or name like 'j%');
使用這種查詢語句(已設置AUTOTRACE),可得到下列結果:
ADDRESS cleveland 1 row selected. Execution Plan SELECT STATEMENT CONCATENATION TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I
select address from address where upper(name) like 'JOHN' AND (name like 'JO%' or name like 'jo%' or name like 'Jo' or name like 'jO' );
得到的結果與以前相同,但是,其執行過程如下所示,表明有4個掃描范圍。
Execution Plan SELECT STATEMENT CONCATENATION TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I TABLE ACCESS BY INDEX ROWID ADDRESS INDEX RANGE SCAN ADDRESS_I