A few things before I answer, Pooja:
First, please post your questions to VizAlerts. That's the official place where you can get help and support with the tool. If you post them in the general forum, you may get confusing answers from folks who aren't familiar with the tool, and mistake your question for one about subscriptions or data-driven alerts.
Secondly, it is not really considered polite to at-mention other community members as a part of a general question. See the @Mention Etiquette Guide for details. We're happy to help you, but there isn't a need to ping Jonathan or I directly unless our expertise is really required. So let the system work for a bit, first.
Thirdly, your answer: Yes there is a way to run a VizAlert more often than every fifteen minutes, not including the test_alert comment. It involves hacking the custom SQL as you mentioned: Subscription For Every 5 minutes. It is more of a hack than anything else at this point, so expect to put some extra effort in during upgrades to subsequent versions of VizAlerts, and potentially upgrades to Tableau Server, testing things to make sure they work.
Finally, is there a particular reason that you need your alerts to run more often than every fifteen minutes? At higher alert volumes, the timing can get tricky since the alerts being processed take longer than five minutes to complete, which can mean that the next run does not start on time.
Thank you for your reply .I will try to make changes in custom SQL. And I am extremely sorry for directly mentioning your name in the post, will take care of this in future.
This post was migrated just to confirm here!