MYSQL-创建视图以查询两个相似的表

Question

I have to like tables Order_Items and Order_Items_Archived which both tables are InnoDB. I would like to create a query that I can pull all the Items from both orders. I am pretty sure I would do this with a VIEW but I cant seem to find reference to just select all records that have the exact same column names and column types.

Example:

select sum(OrderItems_Amount)
from Order_Items_View
where OrderItems_OrderDate = '2017-10-01';

Answer 1

Sounds like you're looking for the union all operator:

CREATE OR REPLACE VIEW order_items_view AS
SELECT * FROM order_items
UNION ALL
SELECT * FROM order_items_archived

Answer 2

You would use a union all query. I would be inclined to add the source. List the columns that you want:

select col1, col2, col3, . . . , 0 as is_archive
from order_items
union all
selecct col1, col2, col3, . . ., 1
from order_items_archive;

You can put a create view statement before the query to turn it into a view.