You can do it with Monitoring Studio KM.
This KM allows you to do numerical extraction on different type of Queries SQL, Commands, SNMP, WBEM, HTTP (REST API) ... etc
If your customer has licensed Oracle KM, it let you monitor custom SQL query result.
Or if you don't mind writing a wrapper program for the SQL query using SQL Plus or jdbc, you can invoke the wrapper program using either LOG KM or Scripting KM.
Hope it helps,