This is a REALLY deep question. Are you looking to build your own? Are you trying trying make sure a specific use case is secure/reliable/good? You can, actual

This is a REALLY deep question. Are you looking to build your own? Are you trying trying make sure a specific use case is secure/reliable/good? You can, actually, build your own SQL processor on top of your own data (or arbitrary data store) - and the last company I worked for was starting to do this (but they were special!).