Comment by saurik

Many of the complaints I hear people make about the entire concept of an "RDBMS" (often then to motivate why the NoSQL solution they decided to start using is better) are actually MySQL-specific issues that do not affect PostgreSQL (or Oracle, or usually SQL Server; I only mention PostgreSQL, as you wanted a concrete experience); one key example is "if you want to change your schema, it requires locking the entire system and rewriting the table" <- no, as the schema is just metadata; you should be able to do these things under first-class transactions, and PostgreSQL supports this just fine.