Facebook guys as I understand it did look carefully at PostgreSQL; at least some of the engineers are very familiar with its internals. They found MySQL satisf

Facebook guys as I understand it did look carefully at PostgreSQL; at least some of the engineers are very familiar with its internals. They found MySQL satisfactory for a variety of reasons including ability to engineer better performance but also replication which was much better in MySQL for a long time. In fact, for an interesting perspective on the "Facebook stuck on MySQL" topic see [1]. Interestingly much Facebook database work has been outside the relational orbit on systems like Cassandra and HBase, as well as RocksDB. The choice for most web properties today is not MySQL vs. PostgreSQL but RDBMS vs. "other" systems. [1] https://dom.as/2011/07/08/stonebraker-trapped/ https://dom.as/2011/07/08/stonebraker-trapped/