没有group by子句，只返回1条记录;返回所需数量的记录

SELECT 
PM.id AS id, PM.email AS email, PM.name AS name, PM.mobile AS mobile, 
PM.country AS country, PM.status AS status, PM.cdate AS joined_date, 
PM.details_status AS details_status, PM.freeze AS freeze, PM.blacklist AS blacklist, 
PM.blacklist_remark AS blacklist_remark, PM.blacklist_adate AS blacklist_adate, 
MA.m_app_id AS app_id, MA.full_name AS replace_name, MAX(MA.ldate) AS ldate, 
MA.service_type AS svc_type 

FROM whatever_db.tw_person_merchant PM 
    LEFT JOIN (
        whatever_db.tw_person_merchant PMM
        INNER JOIN
        whatever_db.tw_merchant_application_details MA 
        ON PMM.app_id = MA.m_app_id
        INNER JOIN 
        whatever_db.tw_merchant_application MAP 
        ON MA.m_app_id = MAP.id
        AND MAP.status NOT IN ('10' , '60')
        AND MA.id = (SELECT max(id) FROM whatever_db.tw_merchant_application_details WHERE m_app_id = PMM.app_id )
    )  ON PM.app_id = MA.m_app_id 

WHERE PM.details_status IN ('90', '0')
AND PM.blacklist = 0 
AND PM.name != ''

-- **here, without the group by clause, the result is just 1 record
GROUP BY PM.id 
ORDER BY PM.id DESC

我正在测试的sql脚本有相关的商人返回，但在中间它只显示1记录，经过反复试验，插入“组由”解决它。但这个“组由”是不是总结，但显示更多的结果比没有它。意想不到的结果和这样的背叛的意义。