The following are limitations specific to the
NDBCLUSTER storage engine:
Machine architecture. The following issues relate to physical architecture of cluster hosts:
All machines used in the cluster must have the same architecture. That is, all machines hosting nodes must be either big-endian or little-endian, and you cannot use a mixture of both. For example, you cannot have a management node running on a PowerPC which directs a data node that is running on an x86 machine. This restriction does not apply to machines simply running mysql or other clients that may be accessing the cluster's SQL nodes.
Adding and dropping of data nodes. Online adding or dropping of data nodes is not currently possible. In such cases, the entire cluster must be restarted.
Backup and restore between architectures. It is also not possible to perform a Cluster backup and restore between different architectures. For example, you cannot back up a cluster running on a big-endian platform and then restore from that backup to a cluster running on a little-endian system. (Bug #19255)
Online schema changes. It is not possible to make online schema changes such as those accomplished using
CREATE INDEX, as the
NDB Clusterengine does not support autodiscovery of such changes. (However, you can import or create a table that uses a different storage engine, and then convert it to
ALTER TABLE. In such a case, you must issue a
FLUSH TABLESstatement to force the cluster to pick up the change.)
sql_log_binhas no effect on data operations; however, it is supported for schema operations.
MySQL Cluster cannot produce a binary log for tables having
BLOBcolumns but no primary key.
Only the following schema operations are logged in a cluster binary log which is not on the mysqld executing the statement: