Bpl or Sql

Hi forgive my complete ignorance in this area but I work in a company that uses a database accessed via a restricted web interface. The database is written using Sql? We have been advised that for future proofing we need to upgrade it and someone is trying to push for a switch to Bpl. I need to swat up to advise on whether we stick to Sql or it’s new version or go with our advice which I think is flawed. We need to ensure whatever we use is widely supported and that obtaining technical support will not be a problem I.e. A large number of trained programmers in th uk south.