获取当前文件上一条与下一条记录的原理是上一条的sql语句,从news表里按从大到小的顺序选择一条比当前ID小的新闻,下一条的sql语句,从news表里按从小到大的顺序选择一条比当前ID大的新闻。
mssqlserver查询方法
其实我做了最简的就是如下写法
代码如下 | 复制代码 |
上一条记录的SQL语句: top 1 * from news where newsid 下一条记录的SQL语句: select top 1 * from news where newsid>id order by newsid ASC |
另一种写未能
id是指当前数据news_id参数
方法一:
代码如下 | 复制代码 |
string nextSql = "select top 1 * from news where news_id > " + id + " order by news_id ASC" |
方法二:
代码如下 | 复制代码 |
|
mysql查询上一条与下一条的办法
如果ID是主键或者有索引,可以直接查找:
方法1:
代码如下 | 复制代码 |
1.select * from table_a where id = (select id from table_a where id 2.select * from table_a where id = (select id from table_a where id > {$id} order by id asc limit 1); |
方法2:
代码如下 | 复制代码 |
1.select * from table_a where id = (select max(id) from table_a where id 2.select * from table_a where id = (select min(id) from table_a where id > {$id}); |
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