Connects to DB2 databases based on config.
Called after connect, once the connection has been registered with the pool.
Override this to attach error handlers or run post-connection setup queries.
Calling pool.destroy() on the connection from here does not throw, but it does not
close the connection either: the pool only takes ownership once this method resolves.
The connection returned by connect
Determine if a connection is still valid or not
DB2 Connection Manager
Get connections, validate and disconnect them. AbstractConnectionManager pooling use it to handle DB2 specific connections Use https://github.com/ibmdb/node-ibm_db to connect with DB2 server