Product Manager for the MySQL Server here - I would like to re-enforce a good point you mention: quirks can be a side-effect of making sure you have a good upg

Product Manager for the MySQL Server here - I would like to re-enforce a good point you mention: quirks can be a side-effect of making sure you have a good upgrade story. Sure; we would prefer not to have them, but you want a vendor which has a strong commitment to backwards compatibility too. There is a balance: and I think we've gotten better at it in the last 5 years. The default is now STRICT mode on (since 5.7/2015 and new configurations since 5.6/2013). Upgrade is a feature too :-) Because of the rate of CVEs at the moment, it is important to keep within the vendor EOL policy. Because MySQL Replication is logical, most users do major-version upgrades without downtime.