Question

我有两张表accounts和calls。 Account表包含帐户详细信息，call表包含date_modified等帐户ID以及parent_id列中帐户ID的其他详细信息。

有很多记录，我需要一个查询来获取所有帐户的最后通话详情（最近一次通话）。

我试过这个但却无法得到结果。

SELECT accounts.id, accounts.name, calls.name subject 
FROM accounts 
INNER JOIN calls ON accounts.id = calls.parent_id 
WHERE accounts.id=(
   SELECT c.parent_id 
   FROM calls c 
   WHERE c.parent_id = calls.parent_id 
   ORDER BY c.date_modified DESC LIMIT 1
)

Answer 1

请尝试此查询并告诉我结果：

SELECT accounts.id, accounts.name, calls.name subject 
FROM accounts 
INNER JOIN calls ON accounts.id = calls.parent_id 
WHERE calls.date = (
   SELECT max(c.date)
   FROM calls c 
   WHERE c.parent_id = calls.parent_id)

Answer 2

尝试此查询：它应该有效。

SELECT * FROM Accounts A
INNER JOIN
(
    SELECT 
        c.parent_id
        ,c.name
        ,c.date_modified
    FROM calls C
    INNER JOIN 
    (
        SELECT 
            parent_id
            ,MAX(date_modified) call_date
        FROM calls 
        GROUP BY parent_id
    ) CC ON CC.parent_id = c.parent_id AND CC.call_date = c.date_modified

) CCC ON CCC.parent_id = A.id

从两个表连接中获取每个记录的最后修改值？

2 个答案: