INSERT INTO Table_3(Field_1,Field_2)
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2我希望如果Table_1 ,Table_2里的数据有更改和新增,Table_3也能随之更新和增加,但是Table_3里Field_1和Field_2联合唯一,请问Update和Insert具体应该怎么写
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2我希望如果Table_1 ,Table_2里的数据有更改和新增,Table_3也能随之更新和增加,但是Table_3里Field_1和Field_2联合唯一,请问Update和Insert具体应该怎么写
要么就是在程序入口处对插入和更新前做判断,记录到table3
INSERT INTO Table_3(Field_1,Field_2)
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2
where not exists(select 1 from table_3 where field_1=table_1.field1 or field_2=table_2.field2)
as
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2
from Table_3 t3
inner join deleted to on t3.Field_1=to.Field_1
inner join inserted tn on to.[主键]=tn.[主键]
需要的查询一下即可.
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2或者如4所说,做个视图即可.
create view my_view
as
SELECT Field1,Field2 FROM Table_1 CROSS JOIN Table_2