Dear Andre, Thanks for your observations, which bear some similarity to what another user reported in Github [1]. I’ll get back to you soon.
Best, Christian [1] https://github.com/BaseXdb/basex/issues/1553 On Fri, Mar 30, 2018 at 10:32 AM, andre weber <a...@gmx.de> wrote: > Hi, > > with the new Version 9 I have encountered a strange performance issue: > - Running a simple xpath-query is fast, as it is using the attribute-index. > Execution time: 59.19 ms > - Putting the same simple xpath-query into a function results in a very poor > performance. No use of the attribute-index here. Execution time: 12578.55 ms > > There where no issues with that in the previous Versions 8.x > > Here’s the setup… > > xquery version "3.1"; > > declare function local:slow_query_here() as node()* > { > prof:time( > db:open("mars","data“)/sec[ @isin = "FR0000125338" ] > ) > (: 12578.55 ms :) > }; > > let $fast_query_here := > prof:time( > db:open("mars","data“)/sec[ @isin = "FR0000125338" ] > ) > (: 59.19 ms :) > > return local:slow_query_here() > > > Here’s the query plan… > <QueryPlan compiled="true" updating="false"> > <GFLWOR type="element()*"> > <Let type="element()*"> > <Var name="$fast_query_here" id="0" type="element()*"/> > <ProfTime name="time(value[,label])" type="element()*"> > <CachedPath type="element()*"> > <ValueAccess index="attribute" type="attribute()*"> > <IndexStaticDb name="mars" database="mars"/> > <Str type="xs:string">FR0000125338</Str> > </ValueAccess> > <IterStep axis="self" test="*:base_isin" type="attribute()*"/> > <CachedStep axis="parent" test="*:option" type="element()*"> > <CachedPath> > <IterStep axis="parent" test="*:option_list" type="element()*"/> > <IterStep axis="parent" test="*:finance" type="element()*"/> > <IterStep axis="parent" test="document-node()" > type="document-node()*"/> > </CachedPath> > </CachedStep> > </CachedPath> > </ProfTime> > </Let> > <ProfTime name="time(value[,label])" type="element()*"> > <CachedPath type="element()*" database="mars"> > <DBNode database="mars" pre="0" type="document-node()"/> > <IterStep axis="descendant" test="*:option_list" type="element()*"/> > <IterStep axis="child" test="*:option" type="element()*"> > <CmpSimpleG op="=" type="xs:boolean" size="1"> > <CachedPath type="attribute()?"> > <IterStep axis="attribute" test="*:base_isin" > type="attribute()?"/> > </CachedPath> > <Str type="xs:string">FR0000125338</Str> > </CmpSimpleG> > </IterStep> > </CachedPath> > </ProfTime> > </GFLWOR> > </QueryPlan> > > Any idea what’s causing the performance drop? > > Thank you for your thoughts! > Andre
