Postgresql如何实现？

鉴于下表：

\d users
                                   Table "public.users"
       Column       |            Type             |               Modifiers
--------------------+-----------------------------+----------------------------------------
 id                 | integer                     | not null
 email              | character varying           | not null default ''::character varying
 encrypted_password | character varying           | not null default ''::character varying
 created_at         | timestamp without time zone |
 address_id         | integer                     |

\d address
          Table "public.address"
  Column  |       Type        | Modifiers
----------+-------------------+-----------
 id       | integer           | not null
 street   | character varying |
 city     | character varying |
 province | character varying |
 zip      | character varying |
 country  | character varying |

写一些SQL来选择居住在XXXX的所有用户

现在，该查询的范围是由最新的first订购的创建时间超过3个月的用户吗

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什么索引可以提高此查询的性能

第一个问题：

select u.id, u.email
from users u
inner join address a
    on u.address_id = a.id
where a.city = 'XXXX'

第二个问题：

select u.id, u.email
from users u
inner join address a
    on u.address_id = a.id
where a.city = 'XXXX' AND
      u.created_at < NOW() - interval '3 months'
order by u.created_at desc

选择u.id、u.email
来自用户u
内部连接地址a
在u.address_id=a.id上
其中a.city='XXXX'和
u、 在

假设您想要选择居住在特定城市的用户，让我们在特定国家“埃塞俄比亚”中选择“亚的斯亚贝巴”

从“用户”中选择*作为a.id=u.address\u id上的“地址”，其中a.city='Addis Ababa'和a.country='Ethiopia'和u.created\u在<当前日期-间隔'3个月'由u.created\u在DESC下订单；

量化

谁住在XXXX

。。。您是要检查某一列，例如

城市

，还是要检查一组地址列？某一列，例如城市。请提供一个最小、完整且可验证的示例：什么索引可以提高此查询的性能？@AlexZywicki您只需编写

[MCVE]即可轻松链接到MCVE页面

欢迎，如果答案解决了您的问题，您可以接受。

SELECT * FROM "users" AS u JOIN "address" AS a ON a.id = u.address_id WHERE a.city = 'Addis Ababa' AND a.country = 'Ethiopia' AND u.created_at < CURRENT_DATE - INTERVAL '3 months' ORDER BY u.created_at DESC;