Re: [Exist-open] Réf. : Re: xquery slow results with attribute predicates

[Wolfgang <wol...@ex...>]

Hi,

There can't be a difference between elements and attributes concerning 
indexes and performance. Both are handled in exactly the same way. There 
must be another reason for the differences you see.

Please try to avoid "where" expressions: eXist's new query-rewriting 
optimizer cannot handle them yet and you will thus not benefit from our 
new optimizations! Most simple where expressions can be rewritten into a 
predicate:

> declare function hr:id($id) as xs:integer {
> 	for $c in $id
> 	where $c/@name = "id"
> 	return $c
> };

becomes

declare function hr:id($id) as xs:integer {
  	for $c in $id[@name = "id"]
  	return $c
};

The "where" is pretty useless here.

Wolfgang