MySQL 9.1 Release Notes
MySQL Server offers a number of choices in storage engines. Since
both NDB and
InnoDB can serve as transactional
MySQL storage engines, users of MySQL Server sometimes become
interested in NDB Cluster. They see
NDB as a possible alternative or
upgrade to the default InnoDB storage
engine in MySQL. While NDB and
InnoDB share common characteristics,
there are differences in architecture and implementation, so that
some existing MySQL Server applications and usage scenarios can be
a good fit for NDB Cluster, but not all of them.
In this section, we discuss and compare some characteristics of
the NDB storage engine used by NDB
9.1 with InnoDB used in
MySQL 9.1. The next few sections provide a technical
comparison. In many instances, decisions about when and where to
use NDB Cluster must be made on a case-by-case basis, taking all
factors into consideration. While it is beyond the scope of this
documentation to provide specifics for every conceivable usage
scenario, we also attempt to offer some very general guidance on
the relative suitability of some common types of applications for
NDB as opposed to
InnoDB back ends.
NDB Cluster 9.1 uses a mysqld
based on MySQL 9.1, including support for
InnoDB 1.1. While it is possible to
use InnoDB tables with NDB Cluster, such tables
are not clustered. It is also not possible to use programs or
libraries from an NDB Cluster 9.1 distribution with
MySQL Server 9.1, or the reverse.
While it is also true that some types of common business
applications can be run either on NDB Cluster or on MySQL Server
(most likely using the InnoDB storage
engine), there are some important architectural and implementation
differences. Section 25.2.6.1, “Differences Between the NDB and InnoDB Storage Engines”,
provides a summary of the these differences. Due to the
differences, some usage scenarios are clearly more suitable for
one engine or the other; see
Section 25.2.6.2, “NDB and InnoDB Workloads”. This in turn
has an impact on the types of applications that better suited for
use with NDB or
InnoDB. See
Section 25.2.6.3, “NDB and InnoDB Feature Usage Summary”, for a comparison
of the relative suitability of each for use in common types of
database applications.
For information about the relative characteristics of the
NDB and
MEMORY storage engines, see
When to Use MEMORY or NDB Cluster.
See Chapter 18, Alternative Storage Engines, for additional information about MySQL storage engines.