Hi everyone,
We are experimenting a small issue with the count() function, and I wanted to
know if you have any idea to reduce the response time of the server :
We have a database containing almost 5.000 descriptions of expert reports from
the 18th century. As a report can take place over several years, we want to
list all the years mentioned in the reports and then count for each year how
many reports we have. Our goal with this query is to produce a filter by year
for our web application.
But, if the first part of the query is quite fast, it is not the case for the
second part… here is a simplified sample of our code :
xquery version "3.1";
declare default element namespace "xpr" ;
(:
to create the xprDB ;)
db:create('xpr',
'https://raw.githubusercontent.com/anrExperts/data/master/db/xpr.xml')
:)
let $years :=
fn:distinct-values(db:open('xpr')/xpr/expertises/expertise/description/sessions/date[@when
castable as xs:date]/fn:year-from-date(@when))
for $year in $years
return
$year || ' : ' (:this first part of the query is quite fast 0.09sec on my old
computer:) ||
fn:count(db:open('xpr')/xpr/expertises/expertise[description/sessions/date[fn:matches(@when,
xs:string($year))]]) (:it takes 5sec to execute the second part of the query:)
Do you see anything we are doing wrong or we can improve to reduce the server
response time ?
We thank you in advance!
Best,
Josselin
