订单详表
orderno(定单id) prono(产品编号) pronum(数量)
1                  1              10
1                  2              20 
1                  3              10
1                  4              10
2                  1               5
2                  2              10
2                  3               5
3                  1              40
3                  5              10产品表
prono(产品编号) name产品名称  
1                品1
2                品2
3                品3
4                品4
5                品5
....我想做一个结果集,根据订单的产品,生成一个结果集
result :
prono(产品编号) name产品名称  数量(对不同订单的同一个产品求和)
1                品1          55
2                品2          30
3                品3          15
4                品4          10   
5                品5          10