mysql group by 多个字段进行分组并获取最新一条的记录

select 
			a.ZNCC_QTNDJL_QTNDZT AS znccQtndjlQtndzt,
			count(*) AS count,
			GROUP_CONCAT(ZNCC_QTNDJL_CFNM,':',b.XT_CFXX_CFBH) AS znccQtndjlCfbh 
		FROM (SELECT * FROM (SELECT * FROM ZNCC_QTNDJL ORDER BY ZNCC_QTNDJL_JCSJ DESC) a GROUP BY  ZNCC_QTNDJL_CFNM ORDER BY ZNCC_QTNDJL_JCSJ DESC LIMIT 100000000
			)  a 
		LEFT JOIN xt_cfxx b on a.ZNCC_QTNDJL_CFNM=b.xt_cfxx_cfnm
		group BY a.ZNCC_QTNDJL_QTNDZT