Xquery-计数元素

Question

如何返回字符串序列？

Answer 1

自2014年以来的XQuery支持您可以使用的group by子句：

for $dept at $pos in //building[year = '1900']/department
group by $key := $dept
order by $pos[1]
return ($key || ' ' ||  count($dept))

https://xqueryfiddle.liberty-development.net/gWcDMen

如果没有XQuery 3支持，则可以使用

let $dept := //building[year = '1900']/department
for $dist-dept in distinct-values($dept)
return 
    concat($dist-dept, ' ', count($dept[. = $dist-dept]))

https://xqueryfiddle.liberty-development.net/gWcDMen/1