ds1的列,向下扩展,并作为参数传给ds2列进行查询,但发现这个ds2查询只会查一次,并没有跟随ds1进行向下扩展查询;aaaaa.zipds1:SELECT '3' aa FROM dualunion all SELECT '2' aa FROM dual union all SELECT '1' aa FROM dualds2:select * from(SELECT '1' aa,'a' bb FROM dual union all SELECT '2' aa,'b' bb FROM dual union all SELECT '3' aa,'c' bb FROM dual) where aa = '${a}'内容为这就是ds2只执行了第一行的传的参数3