NDB Cluster Configuration Files Version (or later) NDB 8.0.13 Type or units integer Default 64 Range 0 - 4294967039 (0xFFFFFEFF) Restart Type N (NDB 8.0.13) • MaxNoOfUniqueHashIndexes • MaxNoOfTriggers • MaxNoOfSubscriptions For each unique index that is not a primary key, a special table is allocated that maps the unique key to the primary key of the indexed table. By default, an ordered index is also defined for each unique index. To prevent this, you must specify the  USING HASH  option when defining the unique index. The default value is 64. Each index consumes approximately 15KB per node. The sum of  MaxNoOfTables ,  MaxNoOfOrderedIndexes , and MaxNoOfUniqueHashIndexes  must not exceed  2$^{32}$  −  2  (4294967294). Internal update, insert, and delete triggers are allocated for each unique hash index. (This means that three triggers are created for each unique hash index.) However, an  ordered  index requires only a single trigger object. Backups also use three trigger objects for each normal table in the cluster. Replication between clusters also makes use of internal triggers. This parameter sets the maximum number of trigger objects in the cluster. The default value is 768. Each  NDB  table in an NDB Cluster requires a subscription in the NDB kernel. For some NDB API applications, it may be necessary or desirable to change this parameter. However, for normal usage with MySQL servers acting as SQL nodes, there is not any need to do so. The default value for  MaxNoOfSubscriptions  is 0, which is treated as equal to  MaxNoOfTables . Each subscription consumes 108 bytes. 4097 Version (or later) NDB 8.0.13 Type or units unsigned Default 0 Range 0 - 4294967039 (0xFFFFFEFF) Restart Type N (NDB 8.0.13) Version (or later) NDB 8.0.13 Type or units integer Default 768 Range 0 - 4294967039 (0xFFFFFEFF) Restart Type N (NDB 8.0.13) Note