SQL> create table test(a varchar2(20));Table createdSQL> insert into test values('2');1 row insertedSQL> insert into test values('12');1 row insertedSQL> insert into test values('玲珑剔透');1 row insertedSQL> commit;Commit completeSQL> select * from test;A--------------------212玲珑剔透SQL> select a from test where length(a)!=lengthb(a);A--------------------玲珑剔透SQL> select a from test where asciistr(a) not like '%%';A--------------------212SQL> select a from test where asciistr(a) like '%%';A--------------------玲珑剔透