CREATE TABLE t1 (f1 INTEGER) Engine=InnoDB; INSERT INTO t1 VALUES (1), (1); connection node_2; SET SESSION wsrep_OSU_method = "RSU"; ALTER TABLE t1 ADD PRIMARY KEY (f1); ERROR 23000: Duplicate entry '1' for key 'PRIMARY' SET SESSION wsrep_OSU_method = "TOI"; SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE TABLE_NAME = 't1'; COUNT(*) = 0 1 INSERT INTO t1 VALUES (1); connection node_1; SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE TABLE_NAME = 't1'; COUNT(*) = 0 1 SELECT COUNT(*) = 3 FROM t1; COUNT(*) = 3 1 INSERT INTO t1 VALUES (1); connection node_2; SELECT COUNT(3) = 4 FROM t1; COUNT(3) = 4 1 DROP TABLE t1;