4050 Overview of NDB Cluster Configuration Parameters  Options  and Variables • ndb_log_empty_epochs : When enabled  epochs in which there were no changes are written to ndb_apply_status and ndb_binlog_index tables  even when log_slave_updates is enabled. • ndb_log_empty_update : When enabled  updates which produce no changes are written to ndb_apply_status and ndb_binlog_index tables  even when log_slave_updates is enabled. • ndb_log_exclusive_reads : Log primary key reads with exclusive locks; allow conflict resolution based on read conflicts. • ndb_log_orig : Whether id and epoch of originating server are recorded in mysql.ndb_binlog_index table. Set using --ndb-log-orig option when starting mysqld. • ndb_log_transaction_id : Whether NDB transaction IDs are written into binary log (Read-only). • ndb-log-updated-only : Log complete rows (ON) or updates only (OFF). • ndb-log-update-minimal : Log updates in minimal format. • ndb_metadata_check : Enable auto-detection of NDB metadata changes with respect to MySQL data dictionary; enabled by default. • Ndb_metadata_blacklist_size : Number of NDB metadata objects that NDB binlog thread has failed to synchronize; renamed in NDB 8.0.22 as Ndb_metadata_excluded_count. • ndb_metadata_check_interval : Interval in seconds to perform check for NDB metadata changes with respect to MySQL data dictionary. • Ndb_metadata_detected_count : Number of times NDB metadata change monitor thread has detected changes. • Ndb_metadata_excluded_count : Number of NDB metadata objects that NDB binlog thread has failed to synchronize. • ndb_metadata_sync : Triggers immediate synchronization of all changes between NDB dictionary and MySQL data dictionary; causes ndb_metadata_check and ndb_metadata_check_interval values to be ignored. Resets to false when synchronization is complete. • Ndb_metadata_synced_count : Number of NDB metadata objects which have been synchronized. • Ndb_number_of_data_nodes : Number of data nodes in this NDB cluster; set only if server participates in cluster. • ndb-optimization-delay : Number of milliseconds to wait between processing sets of rows by OPTIMIZE TABLE on NDB tables. • ndb_optimized_node_selection : Determines how SQL node chooses cluster data node to use as transaction coordinator. • Ndb_pruned_scan_count : Number of scans executed by NDB since cluster was last started where partition pruning could be used. • Ndb_pushed_queries_defined : Number of joins that API nodes have attempted to push down to data nodes. • Ndb_pushed_queries_dropped : Number of joins that API nodes have tried to push down  but failed. • Ndb_pushed_queries_executed : Number of joins successfully pushed down and executed on data nodes. • Ndb_pushed_reads : Number of reads executed on data nodes by pushed-down joins.