A.READ UNCOMMITTED是事務(wù)隔離級(jí)別中最低的B.READ UNCOMMITTED會(huì)出現(xiàn)臟讀C.READ UNCOMMITTED會(huì)出現(xiàn)不可重復(fù)讀D.READ UNCOMMITTED是MySQL默認(rèn)的隔離級(jí)別