PushLive actually uses 2 databases. Following the Installation Instructions – you’ll set one up for the Staging Site and one for the Live Site. It’s actually very safe and simple to use once you’ve got it set up properly.
The trick for most people will be understanding what tables to check or uncheck in the PushLive settings for the various plugins you add to your site…
I do give a good idea on what to check/uncheck for the basic WordPress install, but I can’t possibly monitor every WordPress plugins tables so that’s up to you.
More simply you’ll want to uncheck ONLY the tables that the live site will use to update data (like comment data tables, user data tables, or click or view tracking data tables, etc…). Takes a bit of testing for each added plugin (many plugins won’t need any unchecking or even have their own tables), but it’s pretty easy if you understand databases and database tables.