Ms access msaccess将最近的匹配记录从一个表连接到另一个表

我想要的结果

+--------+-------------+------------+--------+ | Tag | most_recent | Comment | Author | +--------+-------------+------------+--------+ | TAG001 | 2015-07-23 | Something3 | AM | | TAG002 | 2015-07-25 | Something5 | BN | +--------+-------------+------------+--------+ 结果1

+--------+-------------+ | Tag | most_recent | +--------+-------------+ | TAG001 | 2015-07-23 | | TAG002 | 2015-07-25 | +--------+-------------+ 结果2

+--------+-------------+------------+ | Tag | most_recent | Comment | +--------+-------------+------------+ | TAG001 | 2015-07-22 | Something1 | | TAG001 | 2015-07-23 | Something3 | | TAG002 | 2015-07-23 | Something2 | | TAG002 | 2015-07-23 | Something4 | | TAG002 | 2015-07-25 | Something5 | +--------+-------------+------------+ 结果：查询表达式中缺少运算符的语法错误

问题4

从此处修改：

结果：联接时出现语法错误

运气不太好…提前谢谢你

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谢谢。

在Access 2010中，以下内容似乎适用于我：

选择c.标记，c.日期创建为最新，c.注释，c.作者 从…起 选择标记，MaxDate创建为MaxDate 根据评论 按标签分组 医学博士 内连接 作为c的评论 在c.Tag=md.Tag和c.DateCreated=md.MaxDate上

SELECT Comments.[Tag], Max(Comments.[DateCreated]) AS most\_recent
FROM Comments
GROUP BY Comments.[Tag];

+--------+-------------+ | Tag | most_recent | +--------+-------------+ | TAG001 | 2015-07-23 | | TAG002 | 2015-07-25 | +--------+-------------+

SELECT Comments.[Tag], Max(Comments.[DateCreated]) AS most\_recent
FROM Comments
GROUP BY Comments.[Tag];

+--------+-------------+------------+ | Tag | most_recent | Comment | +--------+-------------+------------+ | TAG001 | 2015-07-22 | Something1 | | TAG001 | 2015-07-23 | Something3 | | TAG002 | 2015-07-23 | Something2 | | TAG002 | 2015-07-23 | Something4 | | TAG002 | 2015-07-25 | Something5 | +--------+-------------+------------+

SELECT Status.\*,Comments.\*
FROM Status S
LEFT JOIN Comments C ON S.tag = C.tag
JOIN(SELECT x.tag, MAX(x.DateCreated) AS MaxCommentDate FROM Comments x
GROUP BY x.tag) y ON y.tag = x.tag AND y.MaxCommentDate = x.DateCreated

SELECT
Status.\*,Comments.\*
FROM Status S
LEFT JOIN
(
Comments C
INNER JOIN
(
SELECT
x.tag, MAX(x.DateCreated) AS MaxCommentDate
FROM
Comments x
GROUP BY
x.tag
)
y
ON y.tag = x.tag
AND y.MaxCommentDate = x.DateCreated
)
ON S.tag = C.tag;