Limitations of MySQL sync clusters with replicas
Limitations of MySQL sync clusters with replicas
MySQL sync clusters with replicas are subject to restrictions:
- replication works only with the InnoDB storage subsystem ( MyISAM is not supported);
ALTER TABLE
may cause the cluster to stop — we recommend using the the pt-online-schema-change utility;LOCK/UNLOCK
,GET_LOCK()/RELEASE_LOCK()
requests are not supported;- all tables must have a primary key — otherwise it is impossible to make an
INSERT
record; - XA transactions are not supported due to a possible
ROLLBACK
during theCOMMIT
phase; - transaction can rollback even after
COMMIT
— out of two transactions modifying the same record on different nodes, only one will be successfully completed and the other will be aborted at the cluster level; - When naming temporary tables, do not use names that match the names of permanent tables — such a match will stop replication of the permanent table.
Learn more about the limitations in the official Percona XtraDB Cluster documentation.