Is it possible to have mysql treat row based updates as "upserts"?
Consider using INSERT ... ON DUPLICATE KEY UPDATE or REPLACE statements on the master server.

Just note that:


These are unsafe statements for replication, so statement based replication will produce a warning and divergence is possible - consider using MIXED bin log.
These only work on tables with a single unique key or primary key
If there are differences in auto-increment primary key columns, the statements will update divergent records (hence the unsafe classification) (see the manual)