mysql - 基于第二个表 ID 从第三个表字段返回值

Question

我有这张表

添加 (1)

+----+--------------+--------------+
| id | name of add  | Date         |
+----+--------------+--------------+
|  1 | Add01        | March 01     |
|  2 | Add02        | March 02     |
|  3 | Add03        | March 03     |
|  4 | Add04        | March 04     |
+----+--------------+--------------+

添加类型 (2)

+----+----------+
| id | Add id   |
+----+----------+
| 21 | 1        |  NOTE: Add id of table (2) = id of table (1)
| 22 | 2        |
| 23 | 3        |
| 24 | 4        |
+----+----------+

类型名称 (3)

+----+-----------+--------------+
| id | Type id   | Name         |
+----+-----------+--------------+
| 31 | 21        | Text add     |
| 32 | 22        | Banner       | NOTE: Type id of table (3) = id of table (2)
| 33 | 23        | Video add    |
| 34 | 24        | Other        |
+----+-----------+--------------+

我需要这样的报告:

+--------+-----------+--------------+
| Add id | Add name  | Type of add  |
+--------+-----------+--------------+
|  1     | Add01     | Text add     |
|  2     | Add02     | Banner       |
|  3     | Add03     | Video add    |
|  4     | Add04     | Other        |
+--------+-----------+--------------+

(添加 id 来自表 (1)，添加名称 来自表 (1)，添加类型 来自表 (3))

到目前为止，我可以执行 SELECT query LEFT JOIN table 1 and 2 但我不知道如何从表 3 返回值 Name of type。如何我可以做吗？

Answer 1

再次加入表3:

SELECT t1.`id`          AS `Add id`,
       t1.`name of add` AS `Add name`,
       t3.`Name`        AS `Type of add`
FROM   `ADDS` AS t1
  LEFT JOIN `TYPE OF ADDS`   AS t2 ON t2.`Add id`  = t1.`id`
  LEFT JOIN `NAMES OF TYPES` AS t3 ON t3.`Type id` = t2.`id`