有如下三张表(第一行为字段名)
user用户表:
id | name |
---|---|
1 | aaa |
2 | bbb |
3 | ccc |
chargeRecord充值记录表:
id | userId | money |
---|---|---|
1 | 1 | 10 |
2 | 1 | 2 |
3 | 2 | 4 |
4 | 2 | 6 |
record通话记录表:
id | callId(主叫) | beCallId(被叫) | time(时长) |
---|---|---|---|
1 | 2 | 1 | 23 |
2 | 3 | 1 | 2 |
3 | 2 | 3 | 16 |
如何利用user表里面的id 和充值记录表的userId 以及record表的callId/beCallId做连接
查询 用户名,充值总金额,和通话总时长(主叫时长)
新手谢过大家了!!
回复内容:
有如下三张表(第一行为字段名)
user用户表:
id | name |
---|---|
1 | aaa |
2 | bbb |
3 | ccc |
chargeRecord充值记录表:
id | userId | money |
---|---|---|
1 | 1 | 10 |
2 | 1 | 2 |
3 | 2 | 4 |
4 | 2 | 6 |
record通话记录表:
id | callId(主叫) | beCallId(被叫) | time(时长) |
---|---|---|---|
1 | 2 | 1 | 23 |
2 | 3 | 1 | 2 |
3 | 2 | 3 | 16 |
如何利用user表里面的id 和充值记录表的userId 以及record表的callId/beCallId做连接
查询 用户名,充值总金额,和通话总时长(主叫时长)
新手谢过大家了!!
<code>SELECT user.id AS id, user.name AS name, charge.money AS money, record.time AS time FROM user LEFT JOIN (SELECT userId, SUM(money) AS money FROM chargerecord GROUP BY userId) AS charge ON user.id = charge.userId LEFT JOIN (SELECT callId, SUM(time) AS time FROM record GROUP BY callId) AS record ON user.id = record.callId ORDER BY user.id </code>
怎么查 楼上已经给出了 我有一篇关于多表查询的文章 希望对楼主了解多表查询有帮助:SQL的几种连接:内连接、左联接、右连接、全连接、交叉连接
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