使用
MAX(signin)按ID分组的汇总。这将列出
signin每个最新的
id。
SELECt id, MAX(signin) AS most_recent_signinFROM tblGROUP BY id
要获取完整的单个记录，请
INNER JOIN对仅返回
MAX(signin)每个ID 的子查询执行。
SELECt tbl.id, signin, signoutFROM tbl INNER JOIN ( SELECt id, MAX(signin) AS maxsign FROM tbl GROUP BY id ) ms ON tbl.id = ms.id AND signin = maxsignWHERe tbl.id=1
