求教oracle 数据库 字段求和语句

select t.bm, (select count(*) from a where a.zl1=1 and a.bm=t.bm group by a.bm) as zl1, (select count(*) from a where a.zl1=2 and a.bm=t.bm group by a.bm) as zl1, (select count(*) from b where b.bm=t.bm group by b.bm) as qt from