finished exercise 6

exercise_6.sql

@@ -0,0 +1,8 @@
+SELECT vendor_name, vendor_city, vendor_state
+FROM vendors
+WHERE CONCAT(vendor_state, vendor_city) NOT IN (SELECT CONCAT(vendor_state, vendor_city) AS vendor_citystate
+FROM vendors
+GROUP BY vendor_citystate
+HAVING COUNT(*) > 1);
+
+