SQL Statements for Controlling Group Replication A string containing the result of the operation, for example whether it was successful or not. SELECT group_replication_switch_to_single_primary_mode( member_uuid ); For more information, see Section 18.5.1.2, “Changing a Group’s Mode” • group_replication_switch_to_multi_primary_mode() Changes a group running in single-primary mode to multi-primary mode. Must be issued on a member of a replication group running in single-primary mode. Return value: Example: Syntax: STRING group_replication_switch_to_multi_primary_mode() This function has no parameters. A string containing the result of the operation, for example whether it was successful or not. Return value: Example: SELECT group_replication_switch_to_multi_primary_mode() All members which belong to the group become primaries. For more information, see Section 18.5.1.2, “Changing a Group’s Mode” The following functions enable you to inspect and configure the maximum number of consensus instances that a group can execute in parallel. 13.4.3.5 Functions to Inspect and Configure the Maximum Consensus Instances of a Group • group_replication_get_write_concurrency() Check the maximum number of consensus instances that a group can execute in parallel. This function has no parameters. The maximum number of consensus instances currently set for the group. For more information, see Section 18.5.1.3, “Using Group Replication Group Write Consensus” . Syntax: INT group_replication_get_write_concurrency() Return value: Example: SELECT group_replication_get_write_concurrency() • group_replication_set_write_concurrency() 2787