sql语句，不知道该怎么写

Question

SELECT a.*, b.cername from base a right join deal b on b.baseid=
       a.id
where b.cername = '特种行业许可证' and 
      b.cername in (SELECT cername FROM [cer]
                    WHERE subdepartmentname = '公安部门')

Answer 1

SELECT base.*, deal.cername
FROM base, deal,cer
WHERE (base.id=deal.baseid)and(deal.cername = '特种行业许可证')and(deal.cername=cer.subdepartmentname)and(cer.subdepartmentname = '公安部门')

Answer 2

SELECT base.*, deal.cername
FROM base, deal,cer
WHERE (base.id=deal.baseid)and(deal.cername = '特种行业许可证')or((deal.cername=cer.subdepartmentname)and(cer.subdepartmentname = '公安部门'))

Answer 3

阿来晚了不过还要发表一下SELECT base.*, deal.cername
FROM base, deal,cer
WHERE (base.id=deal.baseid)and(deal.cername=cer.subdepartmentname)and(deal.cername = '特种行业许可证')and(cer.subdepartmentname = '公安部门')(base.id=deal.baseid)and(deal.cername=cer.subdepartmentname)相当于关联
后面的才是条件

Answer 4

SELECT Base.*, Deal.cername
 FROM  base INNER JOIN deal
    INNER JOIN cer 
   ON  Deal.cername = Cer.cername 
   ON  Base.id = Deal.baseid;
 WHERE Deal.cername = '特种行业许可证'
   AND Cer.subdepartmentname = '公安部门'