Clients often use DbVisualizer as their preferred GUI tool to query Vertica. Developers and DBAs tend to leave DbVisualizer open on their desktop while they are off doing some other activity, only to return to find out that DbVisualizer has disconnected from Vertica. Most likely the Database has been configured to terminate sessions that have been idle for some time or the underlying network does the same with TCP/IP connections.
DbVisualizer includes a “Connection Keep-Alive” feature which helps to prevent connections from being closed due to time-outs of this kind by periodically executing a simple SELECT statement.
To enable Keep-Alive for a connection:
1. Open the Object View tab for the connection,
2. Open its Properties tab,
3. Select the Physical Connection category,
4. Modify or enter a simple SQL statement in the Validation and Keep-Alive SQL field, if needed (see note below),
5. Enable Connection Keep-Alive and optionally change the idle time interval,
6. Click the Apply button.