Is it possible to search for a uri whose document contains a certain XPath using cts:uris()? I thought it may be quicker than returning uris from a cts:search. Here is what I have currently:
declare function local:xpath-search($collection) {
for $i in cts:search(//a/b, cts:and-query((cts:collection-query($collection)) ))[1] return fn:base-uri($i)
} ;
Is there a quicker way to return documents that contain a match to the XPath //a/b, using cts:uris()?
You can use cts:element-query() to construct a cts:query that functions similar to the XPath expression //a/b searching for documents that have a elements that have b element descendants. It isn't exactly the same, and might give you some false positives, because it is really more akin to //a//b, but might be acceptable and can be used with cts:uris().
xquery version "1.0-ml";
declare function local:xpath-search($collection) {
cts:uris("", (),
cts:and-query((
cts:collection-query($collection),
cts:element-query(xs:QName("a"),
cts:element-query(xs:QName("b"), cts:and-query(()) ) ) )) )
};
Related
I am writing Xquery function for BaseX which gets one of arguments as name of the element node. This name is then used in Xpath, but in general I cannot convert string to element.
This is how the method looks like
declare function prefix:getElementWithValue($root as document-node()?, $elem as xs:string?, $minVal as xs:float?, $maxVal as xs:float?)
as element()*
{
let $e := element {$elem} {""}
for $x in $root//SUBELEM
return if ($x//$e/#ATTRIB>=$minVal and $x//$e/#ATTRIB<=$maxVal) then ($x)
};
and the call
return prefix:getElementWithValue($db, "SomeElem", 10.0, 10.0)
and I am getting empty response from that. If I replace the $x//$e with $x//SomeElem it returns proper response. From the QueryPlan I see that the $e is treated as literal value. XPATH is not $x//SomeElem/#ATTRIB but $x//$e/#ATTRIB
So my question is how to covert string to type that can be used in XPATH?
XQuery does not have a standard function to evaluate a dynamically-constructed XPath expression.
Many XQuery processors offer some kind of extension function that does this, however. For example, BaseX offers query:eval():
https://docs.basex.org/wiki/XQuery_Module#xquery:eval
Note that variables in XQuery represent values, not fragments of expression text. Your expression $x//$e/#ATTRIB is equivalent to $x//"SomeElem"/#ATTRIB, which is quite different from $x//SomeElem/#ATTRIB.
If you know that $elem will always be an element name, then you can write $x//*[name()=$e]/#ATTRIB. But take care over namespaces.
I'm working on Xpath/Xquery to return values of multiple child nodes based on a sibling node value in a single query. My XML looks like this
<FilterResults>
<FilterResult>
<ID>535</ID>
<Analysis>
<Name>ZZZZ</Name>
<Identifier>asdfg</Identifier>
<Result>High</Result>
<Score>0</Score>
</Analysis>
<Analysis>
<Name>XXXX</Name>
<Identifier>qwerty</Identifier>
<Result>Medium</Result>
<Score>0</Score>
</Analysis>
</FilterResult>
<FilterResult>
<ID>745</ID>
<Analysis>
<Name>XXXX</Name>
<Identifier>xyz</Identifier>
<Result>Critical</Result>
<Score>0</Score>
</Analysis>
<Analysis>
<Name>YYYY</Name>
<Identifier>qwerty</Identifier>
<Result>Medium</Result>
<Score>0</Score>
</Analysis>
</FilterResult>
</FilterResults>
I need to get values of Score and Identifier based on Name value. I'm currently trying with below query but not working as desired
fn:string-join((
for $Identifier in fn:distinct-values(FilterResults/FilterResult/Analysis[Name="XXXX"])
return fn:string-join((//Identifier,//Score),'-')),',')
The output i'm looking for is this
qwerty-0,xyz-0
Your question suggests some fundamental misunderstandings about XQuery, generally. It's hard to explain everything in a single answer, but 1) that is not how distinct-values works (it returns string values, not nodes), and 2) the double slash selections in your return statement are returning everything because they are not constrained by anything. The XPath you use inside the distinct-values call is very close, however.
Instead of calling distinct-values, you can assign the Analysis results of that XPath to a variable, iterate over them, and generate concatenated strings. Then use string-join to comma separate the full sequence. Note that in the return statement, the variable $a is used to concat only one pair of values at a time.
string-join(
let $analyses := FilterResults/FilterResult/Analysis[Name="XXXX"]
for $a in $analyses
return $a/concat(Identifier, '-', Score),
',')
=> qwerty-0,xyz-0
I've been trying to write a query to get distinct attribute values after using if/then to determine whether I'll use the element in the first place. Here's my example xml and the query i've written so far:
<donors>
<donor donor_id="x21" cn_id="x12">
<homeless>$1201</homeless>
<conservation>$300</conservation>
<cancerResearch>$250</cancerResearch>
</donor>
<donor donor_id="x23" cn_id="x13">
<homeless>$121</homeless>
<conservation>$30</conservation>
<cancerResearch>$50</cancerResearch>
</donor>
<donor donor_id="x24" cn_id="x14">
<homeless>$1201</homeless>
<cancerResearch>$250</cancerResearch>
</donor>
<donor donor_id="x25" cn_id="x12">
<homeless>$1201</homeless>
<conservation>$300</conservation>
<cancerResearch>$250</cancerResearch>
</donor>
</donors>
I want to first get all donors who have a child "conservation". I've done the following for that:
<conservationists>
{
for $x in //donor
return
if(exists($x/conservation))
then <conservationist cn_id="{$x/#cn_id}/>
else ()
}
</conservationists>
I tried wrapping the whole thing in distinct-values but that just gave nothing, and every where else I tried doing something to that effect I just ended up with an end tag.
This is one possible way :
<conservationists>
{
for $x in distinct-values(//donor[conservation]/#cn_id)
return
<conservationist cn_id="{$x}"/>
}
</conservationists>
xpathtester demo
The expression distinct-values(//donor[conservation]/#cn_id) returns distinct values of cn_id attribute from donor elements that have at least one conservation child element.
Considering theses xpath expressions :
//*[#id="searchResults"]/div[1]/div[1]/h2/span
//*[#id="searchResults"]/div[3]/div[1]/h2/span
//*[#id="searchResults"]/div[5]/div[1]/h2/span
For your info the div inside search result's class is article searchResult and the one inside article searchResult is header.
I am not sure how to construct an xpath matching all three of the above elements. Is there a tool or a how to guide for that?
Thanks
Use position function
//*[#id="searchResults"]/div[position()=1 or position()=3 or position()=5]/div[1]/h2/span
If, by 'all', you mean all div in even position index, then you can use mod operator to check :
//*[#id="searchResults"]/div[position() mod 2 = 1]/div[1]/h2/span
but if 'all' literally means all, then you don't need index to return all matched elements :
//*[#id="searchResults"]/div/div[1]/h2/span
How can I get H1,H2,H3 contents in one single xpath expression?
I know I could do this.
//html/body/h1/text()
//html/body/h2/text()
//html/body/h3/text()
and so on.
Use:
/html/body/*[self::h1 or self::h2 or self::h3]/text()
The following expression is incorrect:
//html/body/*[local-name() = "h1"
or local-name() = "h2"
or local-name() = "h3"]/text()
because it may select text nodes that are children of unwanted:h1, different:h2, someWeirdNamespace:h3.
Another recommendation: Always avoid using // when the structure of the XML document is statically known. Using // most often results in significant inefficiencies because it causes the complete document (sub)tree roted in the context node to be traversed.