Select t1.字段1,t2.字段1
from t1 left join t2 on t1.字段1 = t2.字段1
Union
Select t1.字段1,t2.字段1
from t2 left join t1 on t1.字段1 = t2.字段1
from t1 left join t2 on t1.字段1 = t2.字段1
Union
Select t1.字段1,t2.字段1
from t2 left join t1 on t1.字段1 = t2.字段1
from t1 full join t2 on t1.字段1 = t2.字段1
from t1 a full join t2 b on a.字段1=b.字段1