Home Database Mysql Tutorial Oracle数据库查询高效分页

Oracle数据库查询高效分页

Jun 07, 2016 pm 03:13 PM
linq oracle Pagination supply database Inquire Efficient

Linq提供了Skip和Take的API可以用于分页,由于使用的是Entity Framework,在好奇的驱使下用EFProfiler查看生成的SQL,才知道这样以下分页更好。 主要就是使用了row_numer()over()这样的分析函数,可以直接找到那第5000行开始的地方,然后在取出30行就行

    Linq提供了Skip和Take的API可以用于分页,由于使用的是Entity Framework,在好奇的驱使下用EFProfiler查看生成的SQL,才知道这样以下分页更好。 主要就是使用了row_numer()over()这样的分析函数,可以直接找到那第5000行开始的地方,然后在取出30行就行了。

<ol>
<li><span><span>select</span><span> * </span></span></li>
<li><span>  <span>from</span><span> (</span><span>select</span><span> * </span></span></li>
<li><span>          <span>from</span><span> (</span><span>select</span><span> t.*, </span></span></li>
<li><span>                       row_number() OVER(<span>ORDER</span><span> </span><span>BY</span><span> </span><span>null</span><span>) </span><span>AS</span><span> </span><span>"row_number"</span><span> </span></span></li>
<li><span>                  <span>from</span><span> yz_bingrenyz t) p </span></span></li>
<li><span>         <span>where</span><span> p.</span><span>"row_number"</span><span> > 5000 </span></span></li>
<li><span>        ) q </span></li>
<li><span> <span>where</span><span> rownum </span></span></li>
</ol>
Copy after login

比较分析:

本机测试前者耗时1.3s,后者仅0.25s,从以下的执行计划也能看出差异来。

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