以下为MYSQL语句演示：

SELECT * FROM t_news AS n ORDER BY n.`News_ID`

当前ID为4，读取上一条记录：

SELECT * FROM t_news AS n WHERE n.`News_ID` < 4 ORDER BY n.`News_ID` DESC  LIMIT 0,1;

SELECT * FROM t_news AS n WHERE n.`News_ID` > 4 ORDER BY n.`News_ID` LIMIT 0,1;

其他数据库，不用limit，改用top关键字即可。