不能从另一个视图查询一个视图？

Question

好的，我正在将一个数据库从Server (我已经错过了)移动到MySql 5.6。我在创建一个有效日期列表时遇到了问题。在Server中，我只是使用CTE来建立数字，然后是月份，然后是数年，然后是一个月中的几天，然后交叉连接到一起创建一个有效的列表。我宁愿这样做，然后创建一个巨大的表，列出从开始到结束的所有有效日期。然而，将其转换为一组视图似乎不起作用：

create view `Numbers` as
    select 0 N union all select 1 union all select 2 union all
    select 3 union all select 4 union all select 5 union all
    select 6 union all select 7 union all select 8 union all select 9;
create view `Months` as
    select n.N+1 MonthNum union all select 11 union all select 12
    from `Numbers` n;

来自MySql的错误:错误代码: 1109。字段列表中的未知表n。

Answer 1

您必须将第二个视图重写如下：

create view `Months` as
    select N+1 MonthNum from `Numbers`
    union all select 11
    union all select 12
;

这是证据

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mysql> use test
Database changed
mysql> create view `Numbers` as
    ->     select 0 N union all select 1 union all select 2 union all
    ->     select 3 union all select 4 union all select 5 union all
    ->     select 6 union all select 7 union all select 8 union all select 9;
Query OK, 0 rows affected (0.05 sec)

mysql> create view `Months` as
    ->     select N+1 MonthNum from `Numbers`
    ->     union all select 11
    ->     union all select 12
    -> ;
Query OK, 0 rows affected (0.03 sec)

mysql>

查看查询的输出

mysql> select * from Months;
+----------+
| MonthNum |
+----------+
|        1 |
|        2 |
|        3 |
|        4 |
|        5 |
|        6 |
|        7 |
|        8 |
|        9 |
|       10 |
|       11 |
|       12 |
+----------+
12 rows in set (0.00 sec)

mysql>

试试看!！