SQL多对多查询

嘿，我正在尝试查询我的数据库表，这些表是在多对多关系中设置的，它们之间有一个表。这里是一个有问题的表格的快速erd

 Homes ----<  Home_Feature  >---- Features

查询的输出：

    Title     Feature   ....
 1  House A   Balcony    
 2  House A   Pool
 3  House A   Garage
 4  House B   Air-Con

谢谢你，谢谢你的帮助

  ____________________EDIT__________________________

嘿，我非常感谢你们到目前为止提供的帮助，我想知道在添加到这个查询和从另一个表中选择列方面，我是否可以得到更多的帮助

当我简单地在SELECT语句中添加另一个表的列和FROM子句中的表时，查询似乎不起作用？我使用的查询如下，但不起作用。再次感谢你的帮助

SELECT homes.title, homes.description, homes.living_room_count, homes.bedroom_count, homes.bathroom_count, homes.price, homes.sqft, home_type.type_name,
    listagg(features.feature_name, ',') WITHIN GROUP (ORDER BY features.feature_name)  features
FROM homes, home_type
INNER JOIN home_feature
ON homes.home_id = home_feature.home_id
INNER JOIN features
ON home_feature.feature_id = features.feature_id
GROUP BY homes.title, homes.description, homes.living_room_count, homes.bedroom_count, homes.bathroom_count, homes.price, homes.sqft;

我得到这个错误：

ORA-00904: "HOMES"."HOME_ID": invalid identifier
00904. 00000 -  "%s: invalid identifier"

---

这取决于您使用的RDBMS，例如MySQL，您可以在一行中用于所有功能的串联：

SELECT homes.home_id,
       max(homes.title), 
       max(homes.description), 
       max(homes.living_room_count), 
       max(homes.bedroom_count), 
       max(homes.bathroom_count),
       GROUP_CONCAT(features.feature_name) features
 FROM homes
 INNER JOIN home_feature
 ON homes.home_id = home_feature.home_id
 INNER JOIN features
 ON home_feature.feature_id = features.feature_id
 GROUP_BY homes.home_id

在ORACLE 11g r2中，您可以使用

---

这里还有一个

它取决于您使用的RDBMS，例如MySQL，您可以在一行中将所有功能串联起来：

SELECT homes.home_id,
       max(homes.title), 
       max(homes.description), 
       max(homes.living_room_count), 
       max(homes.bedroom_count), 
       max(homes.bathroom_count),
       GROUP_CONCAT(features.feature_name) features
 FROM homes
 INNER JOIN home_feature
 ON homes.home_id = home_feature.home_id
 INNER JOIN features
 ON home_feature.feature_id = features.feature_id
 GROUP_BY homes.home_id

在ORACLE 11g r2中，您可以使用

这里还有Oracle 10g版本：

SQL> SELECT homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count,
  2         wm_concat(features.feature_name) features
  3    FROM homes
  4         INNER JOIN home_feature
  5                 ON homes.home_id = home_feature.home_id
  6         INNER JOIN features
  7                 ON home_feature.feature_id = features.feature_id
  8   group by homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count;

TITLE   LIVING_ROOM_COUNT BEDROOM_COUNT BATHROOM_COUNT FEATURES
------- ----------------- ------------- -------------- ------------------------------
House A                 1             3              1 Balcony,Pool,Garage
House B                 1             2              2 Air-Con

和11g，我们可以使用：

Oracle 10g版本：

SQL> SELECT homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count,
  2         wm_concat(features.feature_name) features
  3    FROM homes
  4         INNER JOIN home_feature
  5                 ON homes.home_id = home_feature.home_id
  6         INNER JOIN features
  7                 ON home_feature.feature_id = features.feature_id
  8   group by homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count;

TITLE   LIVING_ROOM_COUNT BEDROOM_COUNT BATHROOM_COUNT FEATURES
------- ----------------- ------------- -------------- ------------------------------
House A                 1             3              1 Balcony,Pool,Garage
House B                 1             2              2 Air-Con

和11g，我们可以使用：

---

您将如何聚合这些功能，以便每个家庭有一个主行？计算它们，csv？您能提供示例表和所需输出吗？您如何聚合功能，以便每个家庭有一个主行？计算它们，csv？您能提供示例表和所需输出吗？？

SQL> SELECT homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count,
  2         listagg(features.feature_name, ',') within group (order by features.feature_name)  features
  3    FROM homes
  4         INNER JOIN home_feature
  5                 ON homes.home_id = home_feature.home_id
  6         INNER JOIN features
  7                 ON home_feature.feature_id = features.feature_id
  8   group by homes.title, homes.living_room_count, homes.bedroom_count, homes.bathroom_count;

TITLE   LIVING_ROOM_COUNT BEDROOM_COUNT BATHROOM_COUNT FEATURES
------- ----------------- ------------- -------------- ------------------------------
House A                 1             3              1 Balcony,Garage,Pool
House B                 1             2              2 Air-Con