The scenario is like this.
A connection pool was configured with application server
Minimum number of connections > 0 were configured.
Hence they will be instantiated at server start up.
I used some of the connections and closed them except one.
Meanwhile DB went down.
The requirement is I want to check if this is a valid connection or not with out using a query (possibly with DUAL) and without using configurable options in application servers ( like TestonReserve).
What could be the simplest way without using the query to check the health of the connection as I need to make sure that it is healthier for next set of steps?
Also for the connection in the above scenario, if I cross check the same with null value, will it validate whether it is healthier or not?
also if I close the connection, will it somehow raise an exception as DB is down? or it will simply logically close the connection and release the same to connection pool irrespective whether DB is up or not?
Apprecaite your insights.