Update 语句是用 stmt.executeUpdate() 方法,而不是用 executeQuery另外,String SQL_Update = new String();SQL_Update = "UPDATE nimak.user SET name = \"周\" WHERE user = \"root\"";这两行不用这样写,这样写相当于初始化了两个字符串了,直接这样写:String SQL_Update = "UPDATE nimak.user SET name = \"周\" WHERE user = \"root\"";...