月份统计

 select sum(decode(a.mm,'01',num,0)) m1 ,
        sum(decode(a.mm,'02',num,0)) m2,
        sum(decode(a.mm,'03',num,0)) m3,
        sum(decode(a.mm,'04',num,0)) m4,
        sum(decode(a.mm,'05',num,0)) m5,
        sum(decode(a.mm,'06',num,0)) m6,
        sum(decode(a.mm,'07',num,0)) m7,
        sum(decode(a.mm,'08',num,0)) m8,
        sum(decode(a.mm,'09',num,0)) m9,
        sum(decode(a.mm,'10',num,0)) m10,
        sum(decode(a.mm,'11',num,0)) m11,
        sum(decode(a.mm,'12',num,0)) m12,
        sum(num)
        from (select count(1) num,              
               to_char(m.optdate, 'MM') mm
          FROM czrzb M
         group by to_char(m.optdate, 'MM')) A