在选择MySQL中选择

我有两个查询，我想如果可能只在一个查询中执行为Select in Select。在选择MySQL中选择

第一个：

SELECT 
users.id 
FROM users 
LEFT JOIN users_date ON users_date.user = users.id 
LEFT JOIN users_varchar ON users_varchar.user = users.id 
WHERE 
abilitato = 1 
AND users_date.key = 'birthday' 
AND users_varchar.key = 'nation' 
AND users_varchar.value = 'US' 
AND (users.reg_date >= '2013-05-31' AND users.reg_date <= '2013-05-31') 
AND (floor(DATEDIFF(NOW(), users_date.value)/365) >= 19 AND floor(DATEDIFF(NOW(), users_date.value)/365) <= 19)

它检索用户ID的列表（按年龄，民族或注册日期过滤）

第二个：

SELECT count(`matches`.`id`) FROM `matches` WHERE (`matches`.`status_home` = 3 AND `matches`.`status_guest` = 3) AND (`matches`.`team_home` = 13 OR `matches`.`team_guest` = 13)

我需要针对该人检索的每个ID执行第二次选择。每一次执行我必须用检索到的ID替换值13。

它有可能执行所有在一个单一的查询select select？

感谢您的进一步帮助

来源

2013-05-31 Zauker

试试这个sql。

SELECT count(`matches`.`id`) 
FROM `matches` m 
INNER JOIN (SELECT users.id as id 
FROM users 
LEFT JOIN users_date ON users_date.user = users.id 
LEFT JOIN users_varchar ON users_varchar.user = users.id 
WHERE abilitato = 1 
AND users_date.key = 'birthday' 
AND users_varchar.key = 'nation' 
AND users_varchar.value = 'US' 
AND (users.reg_date >= '2013-05-31' AND users.reg_date <= '2013-05-31') 
AND (floor(DATEDIFF(NOW(), users_date.value)/365) >= 19 AND floor(DATEDIFF(NOW(), users_date.value)/365) <= 19)) t 
on t.id=m.team_guest 
WHERE (`matches`.`status_home` = 3 AND `matches`.`status_guest` = 3) 
AND (`matches`.`team_home` = 13 OR `matches`.`team_guest` = t.id) 
GROUP BY t.id

来源

2013-05-31 18:28:19 ankurtr

有问题你建议的INNER JOIN，但ON子句是错误的:( 的t.id值可以是在team_home场或team_guest场我还必须有一个参数值改变team_home = 13 – Zauker

你可以表达你想做的显式连接。但是这个问题要求在选择中进行选择。为此，您需要一个相关的子查询。下面是最终的查询：

select users.id, 
     (SELECT count(`matches`.`id`) 
     FROM `matches` 
     WHERE (`matches`.`status_home` = 3 AND `matches`.`status_guest` = 3) AND 
       (`matches`.`team_home` = user.id OR `matches`.`team_guest` = users.id) 
     ) as cnt 
FROM users LEFT JOIN 
    users_date 
    ON users_date.user = users.id LEFT JOIN 
    users_varchar 
    ON users_varchar.user = users.id 
WHERE abilitato = 1 AND users_date.key = 'birthday' AND 
     users_varchar.key = 'nation' AND users_varchar.value = 'US' AND 
     (users.reg_date >= '2013-05-31' AND users.reg_date <= '2013-05-31') AND 
     (floor(DATEDIFF(NOW(), users_date.value)/365) >= 19 AND 
     floor(DATEDIFF(NOW(), users_date.value)/365) <= 19 
    )

（格式化帮助我理解查询越好）

这样做不相关子查询是因为匹配条件的or的一个挑战。

来源

2013-05-31 22:14:47

在选择MySQL中选择

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