我最初在应用程序中有两个表。他们就像
user
------------------------
user_id
column1
column2
..
Columnn
用户帐户信息
user_id
account_number (can have multiple a/c number on single user_id)
column1
column2
..
Columnn
查询就像
SELECT u.column1, uai.column1, uai.Keycolumn2
FROM user u
LEFT OUTER JOIN user_account_info uai on u.user_id = uai.user_id
但后来添加了一个新表 user_account_map 并更改了 user_account_info
用户
user_id
column1
column2
..
Columnn
用户帐户信息
account_number (can have multiple a/c number on single user_id)
column1
column2
..
Columnn
user_account_map
user_id
account_number (can have multiple a/c number on single user_id)
column1
column2
如何重写查询以匹配上一个查询的输出。可以这样写吗
SELECT u.column1, uai.column1, uai.Keycolumn2
FROM user u
LEFT OUTER JOIN user_account_map uam on u.user_id = uam.user_id
LEFT OUTER JOIN user_account_info uai on u.account_number = uai.account_number