Question

我正在处理3个包含以下名称和列的表：

$arr = [["From"=>"Jack", "To"=>"Peter"],
        ["From"=>"Jack", "To"=>"John"],
        ["From"=>"Jack", "To"=>"Ali"],
        ["From"=>"Ali", "To"=>"Jack"],
        ["From"=>"Ali", "To"=>"Martin"],
        ["From"=>"Jack", "To"=>"Barmar"],
        ["From"=>"Peter", "To"=>"John"]];

$result = array();
foreach ($arr as $item) {
   $result[$item['From']][] = $item;
}

Key = UserID

说明：

每个用户都可以在用户和 MobileUsers 表中使用但是，并非所有用户都出现在 PanCards 表中。这是因为只有已分配卡的用户才会出现在 PanCards 表。在这种情况下，用户ID = 3 的 Doe和用户ID = 4 的 Sullivan有卡，因此它们出现在 PanCards 表中

问题：

我想要实现的是过滤掉用户 MobileUsers 表 MobileAccess 相当于是， UserTypeNumber 相当于 1N 用户表格，但 PanCards 表格中不存在。

到目前为止，我在下面的 SQL查询：

array (size=3) 'Jack' => array (size=4) 0 => array (size=2) 'From' => string 'Jack' (length=4) 'To' => string 'Peter' (length=5) 1 => array (size=2) 'From' => string 'Jack' (length=4) 'To' => string 'John' (length=4) 2 => array (size=2) 'From' => string 'Jack' (length=4) 'To' => string 'Ali' (length=3) 3 => array (size=2) 'From' => string 'Jack' (length=4) 'To' => string 'Barmar' (length=6) 'Ali' => array (size=2) 0 => array (size=2) 'From' => string 'Ali' (length=3) 'To' => string 'Jack' (length=4) 1 => array (size=2) 'From' => string 'Ali' (length=3) 'To' => string 'Martin' (length=6) 'Peter' => array (size=1) 0 => array (size=2) 'From' => string 'Peter' (length=5) 'To' => string 'John' (length=4)

结果是一个空表

*Table 1* **Users** UserID UserName UserTypeNumber 1 John 1N 2 Mary 1N 3 Doe 1N 4 Sullivan 2N 5 Sally 1N **Key = UserID** *Table 2* **MobileUsers** Userid MobileAccess 1 Yes 2 Yes 3 Yes 4 Yes 5 No **Key = UserID** *Table 3* **PanCards** UserID CARD_NUMBER 3 2222 4 3333 5 1111

但我想要的是返回以下结果：

SELECT MobileUsers.Userid, MobileUsers.MobileAccess FROM MobileUsers INNER JOIN Users ON MobileUsers.Userid = Users.UserID INNER JOIN PanCards ON Users.UserID = PanCards.UserID WHERE MobileUsers.MobileAccess = 'Yes' AND Users.UserTypeID = '1N' AND MobileUsers.Userid NOT IN (SELECT PanCards.UserID FROM PanCards)

我如何解决此问题并获得正确的结果？

Answer 1

如果您想使用LEFT JOIN，请使用PanCards SELECT mu.* FROM MobileUsers mu JOIN Users u ON mu.Userid = u.UserID LEFT JOIN PanCards pc ON pc.UserID = mu.UserID WHERE mu.MobileAccess = 'Yes' AND u.UserTypeID = '1N' AND pc.UserID IS NULL;并检查不匹配：

PanCards

我认为您的查询无需加入{{1}}即可。

Answer 2

WITH NotPan -- First get users that are not in the PanCards table
AS 
(
select * from Users as u
where u.userid not in (select userid from PanCards)
)
-- Easy from here
select * from NotPan as n
inner join mobileUsers m on m.userid = n.userid
inner join Users as u on n.userid = u.userid
WHERE m.MobileAccess = 'Yes' and u.UserTypeNumber = '1N'

SQL JOIN返回没有值

2 个答案: