分区超过行号的错误

Question

我正在创建一个子查询来选择特定列 DIS_COL 上的不同条目，然后返回这些不同条目的所有其他列，任意选择第一行。

为此，我创建了一个子查询，它使用 over-partition by 仅选择第一行，然后从该子查询中进行选择。

但是我的代码有错误； “ORA-00923: FROM 关键字未在预期位置找到”。

我的代码如下：

select *
from (
   select *,
          row_number() over (partition by DIS_COL order by COL_2) as row_number --ORDER BY FIELD DETERMINES WHICH ROW IS THE FIRST ROW AND THUS WHICH ONE IS SELECTED.
   from MY_TABLE
   ) as rows
where row_number = 1
AND CRITERIA_COL = 'CRIT_1'
OR CRITERIA_COL_2 = 'CRIT_2';

如何更正我的代码以达到预期的效果？

我正在开发一个 Oracle 数据库。

Answer 1

删除as rows。表/查询别名的语法不正确。它是列别名的语法。

select *
from (
   select T.*, 
          row_number() over (partition by DIS_COL order by COL_2) as row_number --ORDER BY FIELD DETERMINES WHICH ROW IS THE FIRST ROW AND THUS WHICH ONE IS SELECTED.
   from MY_TABLE t
   ) 
where row_number = 1
AND (CRITERIA_COL = 'CRIT_1'
OR CRITERIA_COL_2 = 'CRIT_2');

Answer 2

不是ROW_NUMBER，是*,给子查询添加别名：

select *
from (
   select T.*, -- here
          row_number() over (partition by DIS_COL order by COL_2) as row_number --ORDER BY FIELD DETERMINES WHICH ROW IS THE FIRST ROW AND THUS WHICH ONE IS SELECTED.
   from MY_TABLE
   )T as rows -- and here
where row_number = 1
AND CRITERIA_COL = 'CRIT_1'
OR CRITERIA_COL_2 = 'CRIT_2';