One other idea you might want to try (not sure if it will help or not but would
be easy enough to experiment with).
Assuming you have a Lexicon URI, you could use a cts:uris query to identify
those documents containing the chapter, subchapter, or section with the
attribute value. You could then iterate over these URIs with a doc($uri) and a
simple XPath expression to retrieve only the chapter, subchapter, section with
the attribute value. If you don't know the QNames in advance, you could use
xdmp:unpath. Logically, I believe this is what Mike is suggesting below ...
just doing it a bit different. Like I said, don't know if it would be
slower/faster.
Darin.
________________________________
From: Michael Blakeley <[email protected]>
To: General MarkLogic Developer Discussion <[email protected]>
Sent: Wednesday, July 27, 2011 7:59 PM
Subject: Re: [MarkLogic Dev General] xpath to cts query question
You might get a little faster by using doc() for the cts:search arg1, and
relying on XPath to walk the trees. And since you are doing that, don't bother
with filtering in cts:search.
let $qnames :=
for $i in ("chapter", "subchapter", "section")
return xs:QName($i)
return
cts:search(
doc(),
cts:and-query(
(cts:directory-query($coll, "infinity"),
cts:element-attribute-value-query(
$qnames, xs:QName("enum"), $enum))),
"unfiltered")//(chapter | subchapter | section)[@enum eq $enum]
I don't know if that will be faster or slower, but it's worth a try.
Another variation is to go back to the XPath, and enumerate all the possible
path expressions.
/(a[@v eq $v] | a/b[@v eq $v] | a/b/c[@v eq $v])
-- Mike
On 27 Jul 2011, at 16:50 , Will Thompson wrote:
> This is the best I could come up with:
>
> let $qnames := for $i in ("chapter","subchapter","section") return
> xs:QName($i)
> return cts:search(//(chapter|subchapter|section),
> cts:and-query((
> cts:directory-query($coll,"infinity"),
> cts:element-attribute-value-query($qnames,
>xs:QName("enum"),$enum))))[@enum eq $enum]
>
> This is still about twice as fast as the xpath, even if I can't easily work
> around the predicate at the end.
>
> What's interesting is that the value query is slightly faster than the
> element range query. I assume they're both using the range index, and the
> value query is just doing it in less steps.
>
> Thanks for your help.
>
> -Will
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Will Thompson
> Sent: Wednesday, July 27, 2011 6:07 PM
> To: General MarkLogic Developer Discussion
> Subject: Re: [MarkLogic Dev General] xpath to cts query question
>
> The data unfortunately won't allow for a more specific path. I was trying to
> do something along the lines of what Mike suggested to utilize an attribute
> range index, but the problem is that the cts:search will return multiple
> documents because it includes ancestors, while the Xpath does not.
>
> Here's a less vague example:
>
> //(chapter|subchapter|section)[@enum="123"] will only return, say, the
> section that matches,
>
> but this:
>
> cts:search(
> doc(),
> cts:element-attribute-range-query(
> (xs:QName("chapter"), xs:QName("subchapter"), xs:QName("section")),
> "=",
> xs:QName("enum"), $enum)
> )
> )
>
> will return the section and its ancestor chapter and subchapter, since they
> are included in the searchable expression. The only way I could think to work
> around this is separate queries, each with a searchable expression that
> corresponds to the range query.
>
> -Will
>
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Danny Sokolsky
> Sent: Wednesday, July 27, 2011 5:51 PM
> To: General MarkLogic Developer Discussion
> Subject: Re: [MarkLogic Dev General] xpath to cts query question
>
> Another thing that might help is if you know the full path to the nodes.
> With //, it will have to look for the nodes anywhere in the documents.
>
> -Danny
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Michael Blakeley
> Sent: Wednesday, July 27, 2011 3:49 PM
> To: General MarkLogic Developer Discussion
> Subject: Re: [MarkLogic Dev General] xpath to cts query question
>
> xdmp:plan help with that:
>
> ...
> <qry:info-trace>Analyzing path:
>fn:collection()/descendant-or-self::node()/(a|b|c|d|e|f|g)[@foo =
>"bar"]</qry:info-trace>
> <qry:info-trace>Step 1 is searchable: fn:collection()</qry:info-trace>
> <qry:info-trace>Step 2 does not use indexes:
>descendant-or-self::node()</qry:info-trace>
> <qry:info-trace>Step 3 is searchable: (a|b|c|d|e|f|g)[@foo =
>"bar"]</qry:info-trace>
> <qry:info-trace>Path is fully searchable.</qry:info-trace>
> <qry:info-trace>Gathering constraints.</qry:info-trace>
> <qry:info-trace>Step 3 predicate 1 contributed 1 constraint: @foo =
>"bar"</qry:info-trace>
> ...
>
> The cts:query would be something like:
>
> xdmp:plan(
> cts:search(doc(),
> cts:element-attribute-value-query(
> for $i in ('a', 'b', 'c', 'd', 'e', 'f', 'g')
> return xs:QName($i),
> xs:QName('foo'), 'bar')))
>
> If that isn't fast enough, the next step might be an element-attribute range
> index on every element-attribute combination, and switching to
> cts:element-range-query with operator '='.
>
> -- Mike
>
> On 27 Jul 2011, at 15:36 , Will Thompson wrote:
>
>> Thanks Danny. What I'm mainly trying to do is speed up some slow xpath. I've
>> optimized a lot of this module, but this xpath seems to be one of the
>> remaining bottlenecks: //(a|b|c|d|e|f|g)[@foo = "bar"]. I thought that by
>> converting it to a cts:query it would be faster. Or is this Xpath already
>> going to be optimized by MLS?
>>
>> -Will
>>
>> -----Original Message-----
>> From: [email protected]
>> [mailto:[email protected]] On Behalf Of Danny Sokolsky
>> Sent: Wednesday, July 27, 2011 5:20 PM
>> To: General MarkLogic Developer Discussion
>> Subject: Re: [MarkLogic Dev General] xpath to cts query question
>>
>> Hi Will,
>>
>> I might not be understanding what you are doing here, but here are a few
>> ideas.
>>
>> I think you can use that XPath in the first arg of cts:search, as long as
>> you do not put any variables in it. Something like this:
>>
>> cts:search(//(a|b|c|d|e|f|g)[@foo = "bar"], "hello")
>>
>> Also, in cts:query, you can do a cts:element-query with the
>> cts:element-attribute-query as its second arg. Something like:
>>
>> cts:element-query((xs:QName("a"), xs:QName("b")),
>> cts:element-attribute-word-query((xs:QName("a"),
>> xs:QName("b")), xs:QName("foo"), "bar"))
>>
>> -Danny
>>
>> -----Original Message-----
>> From: [email protected]
>> [mailto:[email protected]] On Behalf Of Will Thompson
>> Sent: Wednesday, July 27, 2011 2:51 PM
>> To: General MarkLogic Developer Discussion
>> Subject: [MarkLogic Dev General] xpath to cts query question
>>
>> I'm trying to create the cts equivalent of essentially this:
>>
>> //(a|b|c|d|e|f|g)[@attr = $val]
>>
>> But it seems like I would have join multiple cts:search()s, one for each
>> element, since I only want the matching element, and not its parent (so I
>> can't do something like cts:search(//(a|b|c|d|e|f|g),
>> cts:element-attribute-value-query((xs:QName("a"),...,(xs:QName("g")),xs:QName("attr"),$val)).
>>
>> cts:search(//a,
>> cts:element-attribute-value-query(xs:QName("a"),xs:QName("attr"),$val))
>> | cts:search(//b,
>> cts:element-attribute-value-query(xs:QName("b"),xs:QName("attr"),$val))
>> | cts:search(//c,
>> cts:element-attribute-value-query(xs:QName("c"),xs:QName("attr"),$val))
>> ...
>> | cts:search(//g,
>> cts:element-attribute-value-query(xs:QName("g"),xs:QName("attr"),$val))
>>
>> Is there a better way to do this?
>>
>> Thank you!
>>
>> -Will
>> _______________________________________________
>> General mailing list
>> [email protected]
>> http://developer.marklogic.com/mailman/listinfo/general
>> _______________________________________________
>> General mailing list
>> [email protected]
>> http://developer.marklogic.com/mailman/listinfo/general
>> _______________________________________________
>> General mailing list
>> [email protected]
>> http://developer.marklogic.com/mailman/listinfo/general
>>
>
> _______________________________________________
> General mailing list
> [email protected]
> http://developer.marklogic.com/mailman/listinfo/general
> _______________________________________________
> General mailing list
> [email protected]
> http://developer.marklogic.com/mailman/listinfo/general
> _______________________________________________
> General mailing list
> [email protected]
> http://developer.marklogic.com/mailman/listinfo/general
> _______________________________________________
> General mailing list
> [email protected]
> http://developer.marklogic.com/mailman/listinfo/general
>
_______________________________________________
General mailing list
[email protected]
http://developer.marklogic.com/mailman/listinfo/general_______________________________________________
General mailing list
[email protected]
http://developer.marklogic.com/mailman/listinfo/general
