No. We use embedded SQL. The database is SQL compliant. You do not need to install an engine because all the database functions needed to support SQL are built into our executable.
You can still construct standard SQL commands and query the database, if you wish. The embedded SQL is capable of handling up to 2 billion records, which in most cases is sufficient for our clients.
Of course, the other advantage is that you do not need to pay expensive licenses or install complicated software. All you need is our executable.