Because MySQL 5.7 deprecates INFORMATION_SCHEMA.GLOBAL_STATUS and returns
errors unless show_compatibility_56=ON, the new Galera check determines the
version of the backend and uses either INFORMATION_SCHEMA.GLOBAL_STATUS or
performance_schema.global_status
//mmsd->async_exit_status=mysql_query_start(&mmsd->interr,mmsd->mysql,"SELECT (SELECT IF(VARIABLE_VALUE=4,'YES','NO') FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME='WSREP_LOCAL_STATE') wsrep_local_state, (SELECT IF(VARIABLE_VALUE=0 OR VARIABLE_VALUE='OFF','NO','YES') FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME='READ_ONLY') read_only, (SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME='WSREP_LOCAL_RECV_QUEUE') wsrep_local_recv_queue");
// FIXME : INFORMATION_SCHEMA.GLOBAL_STATUS is deprecated
// FIXME : future versions should be able to detect backend version and use PERFORMANCE SCHEMA instead
mmsd->interr=0;// reset the value
mmsd->async_exit_status=mysql_query_start(&mmsd->interr,mmsd->mysql,"SELECT (SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME='WSREP_LOCAL_STATE') wsrep_local_state, @@read_only read_only, (SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME='WSREP_LOCAL_RECV_QUEUE') wsrep_local_recv_queue , @@wsrep_desync wsrep_desync, @@wsrep_reject_queries wsrep_reject_queries, @@wsrep_sst_donor_rejects_queries wsrep_sst_donor_rejects_queries, (SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME='WSREP_CLUSTER_STATUS') wsrep_cluster_status");