mysql - 无法从其他 View 创建 mysql View

Question

我有以下观点

M_VWPROC_sub1、M_VWPROC_sub2、M_VWPROC_sub3、M_VWPROC_sub4、M_VWPROC_sub5、 M_VWPROC_sub6、M_VWPROC_sub7、M_VWPROC_sub8、M_VWPROC_sub9

我尝试使用以下 sql 创建 View ，但出现以下错误

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'M_VWPROC_sub2 union all M_VWPROC_sub3 union all M_VWPROC_sub4 union all M_VWPROC' at line 2

查询:

CREATE OR REPLACE  VIEW M_VWPROC (UNIT, PS_DATE, LOCALIN, STOCKIN, STOCKOUT) AS 
select inner_sub_table.UNIT, 
       inner_sub_table.PS_DATE, 
       sum(inner_sub_table.LOCALIN)LOCALIN, 
       sum(inner_sub_table.pur) STOCKIN, 
       sum(inner_sub_table.sale) STOCKOUT 
  from M_VWPROC_sub1 
 union all M_VWPROC_sub2 
 union all M_VWPROC_sub3 
 union all M_VWPROC_sub4 
 union all M_VWPROC_sub5
 union all M_VWPROC_sub6 
 union all M_VWPROC_sub7 
 union all M_VWPROC_sub8 
 union all M_VWPROC_sub9) 
       inner_sub_table
 group by inner_sub_table.UNIT, inner_sub_table.PS_DATE;

任何帮助。提前致谢。

Answer 1

union all 的正确语法需要子查询。 。 。这是一个 select 子句。但是，你不能做你想做的事。您需要另一层子查询。像这样的东西:

create view v_YetAnotherView as 
 select * from M_VWPROC_sub1 
 union all select * from M_VWPROC_sub2 
 union all select * from M_VWPROC_sub3 
 union all select * from M_VWPROC_sub4 
 union all select * from M_VWPROC_sub5
 union all select * from M_VWPROC_sub6 
 union all select * from M_VWPROC_sub7 
 union all select * from M_VWPROC_sub8 
 union all select * from M_VWPROC_sub9;

然后:

CREATE OR REPLACE  VIEW M_VWPROC (UNIT, PS_DATE, LOCALIN, STOCKIN, STOCKOUT) AS 
select inner_sub_table.UNIT, 
       inner_sub_table.PS_DATE, 
       sum(yav.LOCALIN)LOCALIN, 
       sum(yav.pur) STOCKIN, 
       sum(yav.sale) STOCKOUT 
  from YetAnotherView yav
  group by yav.UNIT, yav.PS_DATE;

请注意，这种对 View 的荒谬限制(from 子句不能包含子查询)仅限于 MySQL。