Salesflare and MySQL have an active Technology Partnership according to integrations.salesflare.com. There are 182 companies in the Salesflare partner ecosystem and 7 974 companies in the MySQL partner ecosystem. 25 companies exist in both ecosystems, representing 14% of the Salesflare partner ecosystem and 0.31% of the MySQL partner ecosystem. wufoo and Zapier are the largest companies that exist in both ecosystems.
In terms of popularity, MySQL rules. It is the most popular open source SQL database. It is often employed in web application development and is praised for being reliable, inexpensive, and relatively easy to learn and use. Therefore, you can find it being used for large sites such as Google or Facebook.
However, MySQL has been around for a very long time, and since its creation in 1995 and inception into the Oracle Corporation in 2010, there have been other, possibly more desirable RDBMS that have arrived onto the scene. This may be worth a look, especially when you consider what popularity has done to performance of MySQL.
Oracle-backed MySQL is known to suffer from a few performance issues, especially when scaling. Also, because this RDBMS is old, MySQL does not contain some of the more advanced features that some developers may be looking for, or accustomed to using.