As far as I know, there is no such feature available in CA DevTest. However, my team faced some challenges where CA LISA was continuously attempting connections to the database so we developed our custom step to validate DB connection before SQLs execution.
Attached jar supports DB2 connection. It will help you if you are trying to connect to DB2. Let me know in case you want to connect with other databases. I'll make changes and share updated jar.
To use this custom solution, copy attached jar to hotdeploy folder and look for new custom step inside custom steps/ extensions [right click and add step]. This step can be used just before in-built database connection step.
Thanks,
Kumar