连接成功后
Statement stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
// stmt.execute("insert into num values('hello')");
String sql = "select * from num where 1";
ResultSet rs = stmt.executeQuery(sql);
System.out.println("查询完成");
System.out.println(rs.getRow());