NDB Cluster Configuration Files updates on different SQL nodes less often. It is generally not desirable to set this to a value greater than 2000. The query cache  ndb_cache_check_time  are deprecated in MySQL 5.7; the query cache was removed in MySQL 8.0. By the default, executing  RESET SLAVE  causes an NDB Cluster replica to purge all rows from its ndb_apply_status  table. You can disable this by setting  ndb_clear_apply_status=OFF . Determines the role of this SQL node (and NDB Cluster) in a circular (“active-active” ) replication setup.  ndb_slave_conflict_role  can take any one of the values  PRIMARY ,  SECONDARY , PASS , or  NULL  (the default). The replica SQL thread must be stopped before you can change ndb_slave_conflict_role . In addition, it is not possible to change directly between  PASS  and either of  PRIMARY  or  SECONDARY  directly; in such cases, you must ensure that the SQL thread is stopped, then execute  SET @@GLOBAL.ndb_slave_conflict_role = ’NONE’  first. This variable replaces  ndb_slave_conflict_role , which is deprecated as of NDB 8.0.23. For more information, see Section 23.6.11, “NDB Cluster Replication Conflict Resolution” . 4174 • ndb_conflict_role • ndb_clear_apply_status Note Command-Line Format --ndb-clear-apply-status[={OFF|ON}] System Variable ndb_clear_apply_status Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Boolean Default Value ON Command-Line Format --ndb-conflict-role=value Introduced 8.0.23-ndb-8.0.23 System Variable ndb_conflict_role Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Enumeration Default Value NONE Valid Values NONE PRIMARY SECONDARY PASS