Question

对不起这个可怕的头衔，不知道怎么解释这个。我有一个看起来像这样的查询：

SELECT `name`, `latitude`, `longitude`, `indoor`, `address`,
    `phone`, `email`, `website`, `closed`
FROM rocks INNER JOIN 
    (SELECT DISTINCT id FROM rock_types WHERE type="DWS" or type="Top rope")
    AS types ON rocks.id=types.id
WHERE (latitude>-180 AND latitude<180) AND (longitude>-180 AND longitude<180)

除了我现在所获得的内容之外，我还想获得与每个id相关联的类型列表。我怎样才能做到这一点？感谢

Answer 1

以下是使用传统连接语法的方法：

SELECT rocks.name,
       rocks.latitude,
       rocks.longitude,
       rocks.indoor,
       rocks.address,
       rocks.phone,
       rocks.email,
       rocks.website,
       rocks.closed,
       rock_types.type

FROM   rocks,
       rock_types

WHERE  rocks.latitude  > -180                 AND
       rocks.latitude  < 180                  AND
       rocks.longitude > -180                 AND
       rocks.longitude < 180                  AND
       rocks.type_id   = rocks_types.id       AND
       rock_types.type IN ('DWS', 'Top rope')

rocks.id = rocks_types.id执行两个表之间的链接。

以下是使用INNER JOIN编写相同查询的方法（两者都会导致相同的结果）

SELECT rocks.name,
       rocks.latitude,
       rocks.longitude,
       rocks.indoor,
       rocks.address,
       rocks.phone,
       rocks.email,
       rocks.website,
       rocks.closed,
       rock_types.type

FROM   rocks
       INNER JOIN rocks_types ON rocks.type_id = rocks_types.id

WHERE  rocks.latitude  > -180                 AND
       rocks.latitude  < 180                  AND
       rocks.longitude > -180                 AND
       rocks.longitude < 180                  AND
       rock_types.type IN ('DWS', 'Top rope')

编辑：根据您的评论，以下内容将为您提供以逗号分隔的类型列表：

SELECT rocks.name,
       rocks.latitude,
       rocks.longitude,
       rocks.indoor,
       rocks.address,
       rocks.phone,
       rocks.email,
       rocks.website,
       rocks.closed,
       (SELECT    GROUP_CONCAT(DISTINCT rock_types.type SEPARATOR ',')
        FROM      rock_types
        WHERE     rock_types.id = rocks.id                AND
                  rock_types.type IN ('DWS', 'Top rope')
        GROUP BY  rock_types.id
       ) AS type

FROM   rocks

WHERE  rocks.latitude  > -180    AND
       rocks.latitude  < 180     AND
       rocks.longitude > -180    AND
       rocks.longitude < 180

Answer 2

SELECT `name`, `latitude`, `longitude`, `indoor`, `address`,
    `phone`, `email`, `website`, `closed`, 
    (SELECT GROUP_CONCAT(type SEPARATOR ',') FROM rock_types 
        WHERE (type="DWS" or type="Top rope") and  rock_types.id=rocks.id group by id) types
FROM rocks 
WHERE (latitude>-180 AND latitude<180) AND (longitude>-180 AND longitude<180)

需要帮助我的查询

2 个答案: