限制 xquery 中的结果数 [英] Limit number of results in xquery

问题描述

我有以下 Xquery 代码:

for $w in $words
let $freq := (count($corpus[. eq $w]) div count($content2[text() eq $w])) 
order by $freq descending
return <tr><td>{$w}</td><td>{$freq}</td></tr>

$words 是一些在 $corpus 中出现(可能出现多次)的不同词.$content2 是另一个词袋.变量和除法不是那么重要.

$words is some distinct words that appears (may appear multiple times) in $corpus. $content2 is some another bag of words. Variables and division is not that important.

这个xquery列出了一些词的频率计算，有序.

This xquery lists some frequency calculation of words, ordered.

我想做的是将结果限制为 10.我尝试使用位置值，但因为它给了我单词在单词列表中的位置，所以没有成功..

What I want to do is limit the results by 10. I tried to use positional values but as it gives me the position of the word in the word list, it didnt work out..

有什么帮助吗?

推荐答案

使用 subsequence($sequence, $start, $records) 返回结果子集，从记录 $ 开始start(注意 XQuery 从 1 开始计数)返回 records 项.查看限制结果集"XQuery Wikibooks 页面.如何应用从该页面复制的函数的示例:

Use subsequence($sequence, $start, $records) to return a subset of results, starting at record $start (be aware XQuery counts from 1) returning records items. Have a look at "Limiting Result Sets" XQuery Wikibooks Page. An example of how to apply the function copied from this page:

let $sorted-people :=
   for $person in collection($collection)/person
   order by $person/last-name/text()
   return $person

for $person at $count in subsequence($sorted-people, $start, $records)
return
   <li>{ $person/last-name/text() }</li>

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