MySQL 9.4 Reference Manual Including MySQL NDB Cluster 9.4
The following sections describe changes in the implementation of MySQL NDB Cluster in NDB Cluster 9.4.0, as compared to earlier release series. NDB Cluster 9.4 is available as a Development release for preview and testing of new features currently under development. For production, please use NDB 8.4; for more information, see MySQL NDB Cluster 8.4. NDB Cluster 8.0 and 7.6 are previous GA releases which are still supported in production, although we recommend that new deployments for production use MySQL NDB Cluster 8.4.
Major changes and new features in NDB Cluster 9.4 which are likely to be of interest are listed here:
Binary log slicing.
Beinning with NDB 9.4.0, it is possible to divide binary
logging for a MySQL Cluster or for individual
NDBCLUSTER
tables equally
amongst multiple MySQL servers.
For slicing and dividing the binary logging for an entire
cluster, NDB
implements two
mysqld startup options:
--ndb-log-row-slice-count
determines the number of slices into which to divide the
binary log, and thus the number of servers sharing logging
duties; --ndb-log-row-slice-id
identifies the slice for which a given MySQL server is
responsible. See the descriptions of these options for more
information.
Log slicing can be done for a specific NDB
table by adding rows to the ndb_replication
table with appropriate values for the
binlog_row_slice_count
and
binlog_row_slice_id
columns which are
implemented in NDB 9.4.0. For further information and
examples, see
Per-table binary log slicing.
DEFAULT expressions.
Beginning with NDB 9.4.0, MySQL Cluster supports explicit
default expressions for columns of NDB
tables used with the MySQL server, as described in
Section 13.6, “Data Type Default Values”.
Default column value expressions are supported only when accessed using the MySQL server; such expressions are not visible to NDB API applications.
Microsecond node log timestamps.
Timestamps in NDB
node logs are
now printed by default using microsecond resolution. Data
nodes can enable this feature explicitly with the data node
--ndb-log-timestamps=UTC
option; management nodes can also do so using the
ndb_mgmd option
--ndb-log-timestamps=UTC
. For
backwards compatible behavior, set this option to
LEGACY
, which uses the system time zone
and resolution in seconds, as in releases prior to NDB
8.4.6; in NDB 9.4, UTC
is the default.
SQL nodes can use the roughly equivalent option
--log-timestamps
; you should be
aware that this mysqld option does not
accept LEGACY
as a value.
For more information about NDB Cluster node logs, see Section 25.6.2, “NDB Cluster Log Messages”.
MySQL Cluster Manager has an advanced command-line interface that can simplify many complex NDB Cluster management tasks. See MySQL Cluster Manager 9.4.0 User Manual, for more information.