简而言之：
- 简单应用用MySQL，传说中更快。
- 复杂应用使用PostgreSQL，支持SubQuery、View、Stored Procedure，复杂的查询更快。
别人的结论：
Conclusion
MariabDB & MySQL has slight advantages at database writing
PostgreSQL has slight advantages at simple database read query
PostgreSQL has big advantages at complex database read query
As a result, I think that choosing PostgreSQL is a better options for RDBMS - provided that PostgreSQL comes with more features and following standard SQL.
Written on February 12, 2016