Question

我在Oracle中编写了一个如下所示的查询：

select ID, NAME, GEOMETRY from 
(
    select a.*, rownum as rnm from
    (
        select ID, NAME, GEOMETRY from MY_TABLE
        where SDO_ANYINTERACT(GEOMETRY, SDO_UTIL.SDO_GEOMETRY('POLYGON ((670000 6268000, 670000 6269000, 700000 6269000, 700000 6268000, 670000 6268000))')) = 'TRUE'
        order by NAME asc
    ) a
)
where rnm <= 50 and rnm >= 40

内部查询是使用边界框从MY_TABLE中选择行。包含外部查询以启用对结果的分页。

由于某些奇怪的原因，此查询不会产生任何结果。如果我尝试运行子查询：

select ID, NAME, GEOMETRY from MY_TABLE
where SDO_ANYINTERACT(GEOMETRY, SDO_UTIL.SDO_GEOMETRY('POLYGON ((670000 6268000, 670000 6269000, 700000 6269000, 700000 6268000, 670000 6268000))')) = 'TRUE'
order by NAME asc

按预期产生结果列表。如果我运行子查询：

select a.*, rownum as rnm from
(
    select ID, NAME, GEOMETRY from MY_TABLE
    where SDO_ANYINTERACT(GEOMETRY, SDO_UTIL.SDO_GEOMETRY('POLYGON ((670000 6268000, 670000 6269000, 700000 6269000, 700000 6268000, 670000 6268000))')) = 'TRUE'
    order by NAME asc
) a

结果集为空。以某种方式rownum阻止查询产生任何结果。如果我删除rownum，结果将返回到最里面的查询中：

select a.* from
(
    select ID, NAME, GEOMETRY from MY_TABLE
    where SDO_ANYINTERACT(GEOMETRY, SDO_UTIL.SDO_GEOMETRY('POLYGON ((670000 6268000, 670000 6269000, 700000 6269000, 700000 6268000, 670000 6268000))')) = 'TRUE'
    order by NAME asc
) a

我在这做错了什么？我正在运行Oracle 10g ..

Answer 1

with
    my_query as
    (
        select ID, NAME, GEOMETRY from MY_TABLE 
        where SDO_ANYINTERACT(GEOMETRY, SDO_UTIL.SDO_GEOMETRY('POLYGON ((670000 6268000, 670000 6269000, 700000 6269000, 700000 6268000, 670000 6268000))')) = 'TRUE' 
        order by NAME asc 
    )
select *
from
    (
        select /*+ FIRST_ROWS(n) */  my_query.*, rownum rnum
        from my_query
        where rownum <= :last_row_to_fetch
    )
where
    rnum >= :first_row_to_fetch

请参阅this文章。

在Oracle中，当我的内部查询包含SDO_ANYINTERACT时，为什么我不能在外部查询中选择rownum？

1 个答案: