While googling this morning, I came across: Arguments in favour of PostgreSQL – MoodleDocs. Unfortunately, there’s some factual errors about both MySQL and MySQL Cluster.

For a start, it seems as though the comparison is Postgresql versus MyISAM. Now, this isn’t exactly a fair comparison when it comes to some loads – especially anything when you want crash safety or transactions.

With InnoDB however, COMMIT means that the transaction is on disk and durable.

So, onto Cluster. The replication between nodes in a cluster is not asynchronous. When a transaction is COMMITTED, it’s in the main memory of more than one data node. I.e. the D for Durability. We are durable across node failure. A failure of the entire cluster can loose you some transactions, but only those since the last Global Checkpoint.A whole cluster failure should be a very rare event (read: never).

The comparison to Postgresql async writes is incorrect as in this case on COMMIT the transaction is not durable (unlike with MySQL Cluster).