直接通过SQL取分页数据实例
列表页面,之前程序员用了“Wuqi.Webdiyer”的分页插件,慢,且莫明出错。看了下代码,觉得冗余太多,故决定优化一下。
从网上找了些资料,考虑直接在SQL底层,直接只取当前页的数据,再绑定,这样效率应该会高些。
核心的SQL查询语句是这样的:
代码如下 | 复制代码 |
select top @size * from (@sqlstring) a where @key and @key >= (select min(@key) from (select top @end @key from (@sqlstring) a order by @key desc) a) order by @key desc |
其中:
@size:一页的数量;
@sqlstring:原始查询语句;
@key:关键字段/排序字段,它应是唯一字段;
@star:开始记录数索引,star = size*(p-1)+1;
@end:结束记录数索引,end = size*p+1;
若排序不同,则代码应做相应变化:
代码如下 | 复制代码 |
select top @size * from (@sqlstring) a where @key > = (select max(@key) from (select top @star @key from (@sqlstring) a order by @key asc) a) and @key order by @key asc |
我就是这样构建取数据集的方法,然后把相关参数传进来,拼接查询,返回数据集绑定即可。
这个方案暂时未发现出错,效率也有所提升。

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