ASA SQL User's Guide
  Monitoring and Improving Performance
    Using keys to improve query performance

Using foreign keys to improve query performance

The following query lists the orders from the customer with customer ID 113:

SELECT *
FROM sales_order
WHERE cust_id = 113

Information on the Plan tab 

The Plan tab in the Results pane contains the following information:

sales_order <ky_so_customer>

Here ky_so_customer refers to the foreign key that the sales_order table has for the customer table.