Differences Between the NDB and InnoDB Storage Engines

The MySQL Cluster NDB storage engine is implemented using a distributed, shared-nothing architecture, which causes it to behave differently from InnoDB in a number of ways. For those unaccustomed to working with NDB, unexpected behaviors can arise due to its distributed nature with regard to transactions, foreign keys, joins, and other characteristics. These are shown in the following table:

Feature	InnoDB	MySQL Cluster
MySQL Server Version	InnoDB 1.1: 5.5 InnoDB 1.0: 5.1	MySQL Cluster NDB 6.3, 7.0, 7.1: 5.1 MySQL Cluster NDB 7.2: 5.5
InnoDB Availability	InnoDB 1.1 plugin	NDB 6.3, 7.0: InnoDB storage engine NDB 7.1: InnoDB 1.0 plugin support, as of MySQL Cluster NDB 7.1.9a NDB 7.2: InnoDB 1.1 (MySQL Cluster NDB 7.2.1 and later)
Storage Limits	64TB	3TB (Practical upper limit based on 48 data nodes with 64GB RAM each; can be increased with disk-based data and BLOBs)
Foreign Keys	Yes	No (Ignored, as with MyISAM)
Transactions	All standard types	READ COMMITTED
MVCC Non-Blocking Reads	Yes	No
Data Compression	Yes	No (MySQL Cluster checkpoint and backup files can be compressed)
Large Row Support (> 14K)	Supported for VARBINARY, VARCHAR, BLOB, and TEXT columns	Supported for BLOB and TEXT columns only (Using these types to store very large amounts of data can lower MySQL Cluster performance)
Replication Support	Asynchronous and semi-synchronous replication using MySQL Replication	Automatic synchronous replication within a MySQL Cluster. Asynchronous replication between MySQL Clusters, using MySQL Replication
Scaleout for Read Operations	Yes (MySQL Replication)	Yes (Automatic partitioning in MySQL Cluster; MySQL Replication)
Scaleout for Write Operations	Requires application-level partitioning (sharding)	Yes (Automatic partitioning in MySQL Cluster is transparent to applications)
High Availability (HA)	Requires additional software	Yes (Designed for 99.999% uptime)
Node Failure Recovery and Failover	Requires additional software	Automatic (Key element in MySQL Cluster architecture)
Time for Node Failure Recovery	30 seconds or longer	Typically < 1 second
Real-Time Performance	No	Yes (Low latency)
In-Memory Tables	No	Yes (Some data can optionally be stored on disk; both in-memory and disk data storage are durable)
NoSQL Access to Storage Engine	Native memcached interface in development (see the MySQL Dev Zone article NoSQL to MySQL with Memcached)	Yes Multiple APIs, including C++, HTTP/REST, Java and JPA (MySQL Cluster NDB 7.1 and later); Memcached (MySQL Cluster NDB 7.2) and later)
Concurrent and Parallel Writes	Not supported	Up to 48 writers, optimized for concurrent writes
Conflict Detection and Resolution (Multiple Replication Masters)	No	Yes
Hash Indexes	No	Yes
Online Addition of Nodes	Read-only replicas using MySQL Replication	Yes (all node types)
Online Upgrades	No	Yes
Online Schema Modifications	No	Yes
Real-Time Performance	No	Yes

http://docs.oracle.com/cd/E17952_01/refman-5.1-en/mysql-cluster-ndb-innodb-engines.html