Finding who doesn't sell to a certain place...

Hi all,

I have a Vendor table which links to an Order table via VendorID. I have a Customer table that also links to the Order table via CustomerID.

This means the order table provides a list of all orders, and the IDs of the Customers who made the orders, and the Vendors who handled the orders. For a given order, I can find the state that the customer is from (using Customer table's State field).

This means I can get where the Vendor's sell too. I need to use a sql query to produce a list of vendor's that have NEVER sold to a customer New York. How do I do this? I just cannot get my head around it.

Thanks.

Hi ,

You table structure must be like this

Vendor_table (vendor_id , vendor_name)
order_table(order_id , vendor_id , customer_id )
customer_table (customer_id , state_name)

SELECT vendor_name FROM vendor_table WHERE vendor_id IN
(SELECT T1.vendor_id from order_table T1 , customer_table T2 WHERE T1.customer_id = T2.customer_id AND T2.state_name <> 'New York'
)

Let me know if you still face any problem