> I believe MySQL needed such a tool because it had known replication
> synchronization problems --- Postgres does not, so has no such tool.
I agree with Bruce here. In DB2, for HADR (similar to PG replication)
there is no tool which checks whether primary and standby are same so
that there is no surprise after a failover. I am pretty same is true
for Oracle Dataguard.
If a RDBMS is offering a tool to check for consistency, there is a
high likelihood it is because of inherent problems.