Overview of NDB Cluster Configuration Parameters, Options, and Variables • ndb_use_exact_count : Use exact row count when planning queries. • ndb_use_copying_alter_table : Use copying ALTER TABLE operations in NDB Cluster. • Ndb_trans_hint_count_session : Number of transactions using hints that have been started in this session. • ndb_table_temporary : NDB tables are not persistent on disk: no schema files are created and tables are not logged. • ndb_table_no_logging : NDB tables created when this setting is enabled are not checkpointed to disk (although table schema files are created). Setting in effect when table is created with or altered to use NDBCLUSTER persists for table’s lifetime. • Ndb_system_name : Configured cluster system name; empty if server not connected to NDB. • Ndb_slave_max_replicated_epoch : Most recently committed NDB epoch on this replica. When this value is greater than or equal to Ndb_conflict_last_conflict_epoch, no conflicts have yet been detected. • ndb_slave_conflict_role : Role for replica to play in conflict detection and resolution. Value is one of PRIMARY, SECONDARY, PASS, or NONE (default). Can be changed only when replication SQL thread is stopped. See documentation for further information. • ndb_show_foreign_key_mock_tables : Show mock tables used to support foreign_key_checks=0. • ndb_schema_dist_upgrade_allowed : Allow schema distribution table upgrade when connecting to NDB. • ndb_schema_dist_timeout : Time to wait before detecting timeout during schema distribution. • ndb_schema_dist_lock_wait_timeout : Time during schema distribution to wait for lock before returning error. • Ndb_scan_count : Total number of scans executed by NDB since cluster was last started. • ndb_row_checksum : When enabled, set row checksums; enabled by default. • ndb_report_thresh_binlog_mem_usage : Threshold for percentage of free memory remaining before reporting binary log status. • ndb_report_thresh_binlog_epoch_slip : NDB 7.5.4 and later: Threshold for number of epochs completely buffered, but not yet consumed by binlog injector thread which when exceeded generates BUFFERED_EPOCHS_OVER_THRESHOLD event buffer status message; prior to NDB 7.5.4: Threshold for number of epochs to lag behind before reporting binary log status. • Ndb_replica_max_replicated_epoch : Most recently committed NDB epoch on this replica. When this value is greater than or equal to Ndb_conflict_last_conflict_epoch, no conflicts have yet been detected. • ndb_recv_thread_cpu_mask : CPU mask for locking receiver threads to specific CPUs; specified as hexadecimal. See documentation for details. • ndb_recv_thread_activation_threshold : Activation threshold when receive thread takes over polling of cluster connection (measured in concurrently active threads). • ndb_read_backup : Enable read from any replica for all NDB tables; use NDB_TABLE=READ_BACKUP={0|1} with CREATE TABLE or ALTER TABLE to enable or disable for individual NDB tables. 4051