SQL分页查询
分页sql查询在编程的应用很多,主要有存储过程分页和sql分页两种,我比较喜欢用sql分页,主要是很方便。为了提高查询效率,应在排序字段上加索引。sql分页查询的原理很简单,比如你要查100条数据中的30-40条,你先查询出前40条,再把这30条倒序,再查出这倒序后的前十条,最后把这十条倒序就是你想要的结果。
下面把sql分页查询的原理用sql语句表现一下:
-- 分页 升序(搜出的结果再倒序)
SELECT TOP 10 * from (SELECT TOP 40 * from A01 ORDER BY A00 ASC) AS T ORDER BY A00 DESC
-- 分页 升序
SELECT * from (SELECT TOP 10 * from (SELECT TOP 40 * from A01 ORDER BY A00 ASC) AS T ORDER BY A00 DESC) AS T1 ORDER BY A00 ASC
-- 分页 降序(搜出的结果再倒序)
SELECT TOP 10 * from (SELECT TOP 40 * from A01 ORDER BY A00 DESC) AS T ORDER BY A00 ASC
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Questions
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参考文献:http://www.cnblogs.com/chenxizhang/archive/2009/04/23/1441913.html
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