Example 4: Outer Join, the Correct Answer - Teradata Database

Finally, we have the correct answer. This example is an outer join that provides the desired answer to the original business question.

     SELECT c.custnum, b.monthly_revenue

     FROM sampdb.customer AS c

     LEFT OUTER JOIN sampdb2.revenue AS b ON c.custnum = b.custnum

     AND   b.data_year_month = 199707

     WHERE c.district ='K'

     AND  (c.service_type = 'ABC' 

     OR    c.service_type = 'XYZ')

     ORDER BY 1;

This query returns 18,034 rows.