SQL-99中,在select中使用distinct关键字后,在order by中出现的字段名称不能超过select子句的范围,如:
SQL> select distinct ename,sal from emp order by deptno;
select distinct ename,sal from emp order by deptno
*
ERROR at line 1:
ORA-01791: not a SELECTed expression
SQL> select distinct ename,sal from emp order by sal;
ENAME SAL
———- ———-
SMITH 800
JAMES 950
来自 “ ITPUB博客 ” ,链接:http://blog.itpub.net/37724/viewspace-152576/,如需转载,请注明出处,否则将追究法律责任。
转载于:http://blog.itpub.net/37724/viewspace-152576/