I think MySQL's edge is just that is was initially perceived to be simpler to set up. Perhaps that is true or not, but the perception was created. The result

I think MySQL's edge is just that is was initially perceived to be simpler to set up. Perhaps that is true or not, but the perception was created. The result was a massive head start. You now have a huge pool of users, support and knowledge, which makes it a safe choice. (notice I say safe, not necessarily the best) Outside of the startup community developers don't have such a great appetite for risk, especially with their data. I'm one of those people - I just know My SQL better. It has nothing to do with ease of installation or building queries. It has to do with troubleshooting. I know how to tune MySQL and troubleshoot. I know how to install and use other systems but it introduces risk for me to put them into production without a very compelling reason. I would happily use another system if there were a db admin to take responsibility for running the server. In fact my favorite db is Oracle, but I have no experience as DB admin on that platform.