SELECT

B.CALDAY,A.BMZHMS,SUM(B.RS) as RS 

FROM

(

SELECT DISTINCT

CALDAY,COUNT(EMPLOYEE) as RS, ZICZG0010

FROM

"_SYS_BIC"."CB.BL.YW/ZBL_ZDEYG001"

GROUP BY，CALDAY,ZICZG0010 ) B

RIGHT JOIN  "_SYS_BIC"."ZBMJJB_BM" A 

ON A.BMZH = B.ZICZG0010 

（！这里查1个时间关联语句！）

WHERE A.BMZHMS = '东安店'

group by CALDAY,BMZHMS

思路是先把ab两个表按编号join，作为基础表，然后按部门名称group by 求人数

select * from

(select * from a left join b on a.bmhz=b.ziczg0010) c

where BMZHMS = 东安店

SELECT COUNT(1)

  FROM A, B

 WHERE A.BMZH = B.ZICZG0010

   AND A.BMZHMS = '东至店'

   AND B.CADAY = LAST_DAY(ADD_MONTHS(TO_DATE('2021-03', 'YYYY-MM') - 1))