answering directly to the subject: i do hope so. SQL too often introduces only a layer of complexity between the server-side application and the storage, while most of times an application could be designed to just use the filesystem, which is a database on its own by the way: it's a big, usually efficient, lookup table that maps keys (file paths) to values (file contents).
why store passwords through SQL when a server application could just use a specific directory containing one file for each user, each file named with the username and containing his password (without any file format, just the password, possibly hashed or encrypted)? the operating system I/O cache should be able to handle that efficiently and the advantage would be the elimination of the dependence on another software, the DBMS.