Well, I'm sure on a site about RDBMSes, you're gonna get some skewed results. In the wild, MySQL sees higher use than PostgreSQL. That said, as an old coworker would say, MySQL is the PHP of RDBMSes. Ubiquitous, gets the job done, and works well mostly. Of course it does horrendous comparisons, conversions, and mutilations of data. Exactly the thing a database should not do.
When did I conflate the two? For that matter, how do you measure "popularity" of a piece of software? You could just as well say a piece of software is popular because everyone knows and loves it or because everyone uses it and hates it. Webster gives you "liked or enjoyed by many people" and "accepted, followed, used, or done by many people".
