两表连接--一题

2个表：
table1：
prd_no       init_qty
A             19
B             10
C             3

TABLE2:
prd_no       adj_qty
A               3
D               18
E               19

现在想要得到这样的查询结果：
prd_no       init_qty       adj_qty
A                19            3
B                10            0
C                3             0
D                0             18
E                0             19
查询语句应该怎么写？
sql方法：
-------------------------------
select temps.prd_no,IsNull(init_qty,0),IsNull(adj_qty,0) from (select prd_no from table1 union select prd_no from table2) as temps left join table1
 on temps.prd_no = table1.prd_no left join table2 on temps.prd_no = table2.prd_no 
----------------------------
select table1.prd_no,IsNull(init_qty,0) as init_qty,IsNull(adj_qty,0) as adj_qty from table1 left join table2 on table1.prd_no = table2.prd_no
union
select table2.prd_no,IsNull(init_qty,0) as init_qty,IsNull(adj_qty,0) as adj_qty from table2 left join table1 on table2.prd_no = table1.prd_no