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• Configure Tomcat to accept only SSL connections to the  Database Connector. This encrypts data sent between the hosted  Server and the Database Connector installed in your local machine, thus protecting the queryKey.
• Create a SSL self-signed certificate and install in Tomcat’s keystore. The self-signed certificate will ensure that the data being transmitted and received by the  Database Connector is private and cannot be snooped by anyone who may be eavesdropping on the connection.
• If you are You can find more details here about running the  Database Connector under Tomcat you can find more details here. 

The queryKey attribute

The queryKey attribute enables a password authentication mechanism that limits query execution to only those who know the queryKey password string. Every HTTP request that is sent to the database connector to execute that query must contain the key. The connector will deny all requests that do not contain the key.
 
For example, given the configuration below:

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