alter class /m3event/entity/node drop column component -- { onerror(continue) } ; SELECT * FROM /m3event/entity/node limit 1 /** output() **/ ; alter class /m3event/entity/node add column component component[1..1] '组件' ; -- alter class /test/malert_status add column v_test int ; -- SELECT -- identifier, agent, node, v_varchar, connect -- FROM -- /test/malert_status /** output() **/ ; SELECT * FROM /m3event/entity/node limit 1 /** output() **/ ;