For SQL (Database Management Systems):

The tables are

CUSTOMERS

-CUSTOMER_ID

-CUSTOMER_FIRST_NAME

-CUSTOMER_LAST_NAME

-CUSTOMER_CITY

ORDER_DETAILS

-ORDER_ID

-ORDER_QTY

ORDERS

-ORDER_ID

-CUSTOMER_ID

A. Find the name and phone number of each vendor who has a cooperating vendor. Hint: the vendors for whom the field Cooperating_Vendor_id is not empty

B. Now find additionally the name and phone number of the cooperating vendor. Present these two columns as: cooperating vendor and cooperating vendor phone.

C. Modify the above query to report all vendors. If they are have a cooperating vendor, report their name if not report N/A.