alter table performance_schema.global_status add column foo integer; ERROR 42000: Access denied for user 'root'@'localhost' to database 'performance_schema' truncate table performance_schema.global_status; ALTER TABLE performance_schema.global_status ADD INDEX test_index(VARIABLE_NAME); ERROR 42000: Access denied for user 'root'@'localhost' to database 'performance_schema' CREATE UNIQUE INDEX test_index ON performance_schema.global_status(VARIABLE_NAME); ERROR 42000: Access denied for user 'root'@'localhost' to database 'performance_schema'