> Having used both extensively, I'd say that there's a lot of knowledge when using mysql that's basically "introducing complexity into your application and quer

> Having used both extensively, I'd say that there's a lot of knowledge when using mysql that's basically "introducing complexity into your application and query pattern to work around the optimiser being terrible at doing the sensible thing" and then there's lots of knowledge when administrating postgresql that's "having to pick and choose lots of details about your topology and configuration because you get a giant bag of parts rather than something that's built to handle the common cases out of the box". This completely maps to my experience as well. I still believe Postgres' defaults being set to use an absolute minimum footprint, especially prior to PostgreSQL 9, significantly impacted it's adoption. It's better now, although IMO it could still do with an easier configuration where you could flag the install as dev/shared or prod/standalone to provide more sensible settings for the most common situations. Like, gosh, I'd like to be able to stand up an instance and easily tell it to use 90% of the system memory instead of 100 MB or whatever it was. But the MySQL issues were much worse. Outer join and subquery problems, the lack of functions like ROW_NUMBER(), a a default storage engine that lacked transactions and fsync(), foreign keys that don't do anything, etc. I've met so many people who think MySQL limitations are RDBMS limitations, or don't understand database fundamentals because MySQL just didn't implement them properly. Then again, I also remember when the best reason to use MySQL was the existence of GROUP_CONCAT(), which everything else lacked for religious reasons. I also vividly remember prior to MySQL 5.5 when new users of PostgreSQL, Oracle, or MS SQL Server would discover that, instead of making a guess for what you wanted, the RDBMS would actually return error messages and expect you to understand and solve them deterministically. And somehow they would be angry about it! Old MySQL (mostly 3.3, but 4.0 and 4.1, too) used to silently truncate data, or allow things like February 31 in a date field, or silently allow non-deterministic GROUP BY, or only reporting warnings when you explicitly asked for them really undermined the perception of MySQL to database folks. This wasn't that long ago, either.