Example xquery needed to write output to an local xml file
Dear all, I am new on the block here, and trying to find my way around BaseX, which seems to meet my needs for my research on digital museum collection data analysis. I have a very large collection of xml files (> 600000 files) that I am querying, and I want to write the returned result immediately in a file. The following xquery (see below) is not working, which probably comes as no surprise to you all. But to get me started, I would like to have a simple example that works. Any example would do. Hope anyone can help me out with this. Thanks very much, best, Marco. ===== declare variable $data := collection(PRODRMCollectionItems); declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD'; (:This is where all the work is happening:) declare function local:process-data ($nodes as item()*) as element (root) { <RMCollectionItemsDATA created="{current-dateTime()}"> { for $a in $nodes//artObjectGetResponse/artObject[objectNumber eq 'NG-NM-1395-A'] return <item>{$a}</item> } </RMCollectionItemsDATA> }; (:here we store stuff:) let $filename := concat($output, "marco.xml") return file:write($filename, local:process-data($data)) =====
Hi Marco - Are you missing a separator ('\') in your $output variable, or in your `fn:concat($output, '\', 'marco.xml')`? Here's a similar example that's working for me: ``` declare variable $data := (1, 2, 3, 4); declare variable $output := '/home/bridger/'; declare function local:process-data( $seq as item()* ) as item()* { <test created="{fn:current-dateTime()}"> { for $s in $data return( <item>{$s}</item> ) } </test> }; let $filename := "bridger.xml" return file:write($output || $filename, local:process-data($data)) ``` I hope this is helpful! Best, Bridger On Thu, Sep 6, 2018 at 11:13 AM Marco Roling <marcoroling@hotmail.com> wrote:
Dear all,
I am new on the block here, and trying to find my way around BaseX, which seems to meet my needs for my research on digital museum collection data analysis.
I have a very large collection of xml files (> 600000 files) that I am querying, and I want to write the returned result immediately in a file. The following xquery (see below) is not working, which probably comes as no surprise to you all.
But to get me started, I would like to have a simple example that works. Any example would do.
Hope anyone can help me out with this.
Thanks very much, best, Marco.
=====
declare variable $data := collection(PRODRMCollectionItems); declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD';
(:This is where all the work is happening:) declare function local:process-data ($nodes as item()*) as element (root) { <RMCollectionItemsDATA created="{current-dateTime()}"> { for $a in $nodes//artObjectGetResponse/artObject[objectNumber eq 'NG-NM-1395-A'] return <item>{$a}</item> } </RMCollectionItemsDATA> };
(:here we store stuff:) let $filename := concat($output, "marco.xml") return file:write($filename, local:process-data($data)) =====
You maybe don't want to start by writing to a file. You want to separate "did the query produce something sensical" and "does the file write do what I expect" as sources of error so you can't try to debug the wrong thing for a few hours. return (: file:write($output || $filename, :) local:process-data($data) (: ) :) can be a remarkably useful construct until you like what you're seeing. The BaseX GUI very sensibly truncates the output so you can't crush it. -- Graydon On Thu, Sep 6, 2018 at 11:32 AM Bridger Dyson-Smith <bdysonsmith@gmail.com> wrote:
Hi Marco - Are you missing a separator ('\') in your $output variable, or in your `fn:concat($output, '\', 'marco.xml')`?
Here's a similar example that's working for me: ``` declare variable $data := (1, 2, 3, 4); declare variable $output := '/home/bridger/';
declare function local:process-data( $seq as item()* ) as item()* { <test created="{fn:current-dateTime()}"> { for $s in $data return( <item>{$s}</item> ) } </test> };
let $filename := "bridger.xml" return file:write($output || $filename, local:process-data($data)) ```
I hope this is helpful! Best, Bridger
On Thu, Sep 6, 2018 at 11:13 AM Marco Roling <marcoroling@hotmail.com> wrote:
Dear all,
I am new on the block here, and trying to find my way around BaseX, which seems to meet my needs for my research on digital museum collection data analysis.
I have a very large collection of xml files (> 600000 files) that I am querying, and I want to write the returned result immediately in a file. The following xquery (see below) is not working, which probably comes as no surprise to you all.
But to get me started, I would like to have a simple example that works. Any example would do.
Hope anyone can help me out with this.
Thanks very much, best, Marco.
=====
declare variable $data := collection(PRODRMCollectionItems); declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD';
(:This is where all the work is happening:) declare function local:process-data ($nodes as item()*) as element (root) { <RMCollectionItemsDATA created="{current-dateTime()}"> { for $a in $nodes//artObjectGetResponse/artObject[objectNumber eq 'NG-NM-1395-A'] return <item>{$a}</item> } </RMCollectionItemsDATA> };
(:here we store stuff:) let $filename := concat($output, "marco.xml") return file:write($filename, local:process-data($data)) =====
Hi Graydon On Thu, Sep 6, 2018 at 11:41 AM Graydon Saunders <graydonish@gmail.com> wrote:
You maybe don't want to start by writing to a file. You want to separate "did the query produce something sensical" and "does the file write do what I expect" as sources of error so you can't try to debug the wrong thing for a few hours.
This is a great point - thanks for the reminder!
return (: file:write($output || $filename, :) local:process-data($data) (: ) :)
can be a remarkably useful construct until you like what you're seeing. The BaseX GUI very sensibly truncates the output so you can't crush it.
And again!
-- Graydon
Cheers,
Bridger
Hi Marco, BaseX sounds like a good fit for your requirements to me :) You dont say what your error is, but you have declared local:process-data as returning an element named <root> whereas the code is returning an element named <RMCollectionItemsDATA>. Perhaps it should be: declare function local:process-data ($nodes as item()*) as element ( RMCollectionItemsDATA ) or ... as element ( * ) Also I suspect you want an additional \ in your o/p path declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD*\*'; Regards /Andy ----------------------------------- declare variable $data := collection(PRODRMCollectionItems); declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD*\*'; (:This is where all the work is happening:) declare function local:process-data ($nodes as item()*) as element ( *RMCollectionItemsDATA*) { <RMCollectionItemsDATA created="{current-dateTime()}"> { for $a in $nodes//artObjectGetResponse/artObject[objectNumber eq 'NG-NM-1395-A'] return <item>{$a}</item> } </RMCollectionItemsDATA> }; (:here we store stuff:) let $filename := concat($output, "marco.xml") return file:write($filename, local:process-data($data)) On 6 September 2018 at 16:13, Marco Roling <marcoroling@hotmail.com> wrote:
Dear all,
I am new on the block here, and trying to find my way around BaseX, which seems to meet my needs for my research on digital museum collection data analysis.
I have a very large collection of xml files (> 600000 files) that I am querying, and I want to write the returned result immediately in a file. The following xquery (see below) is not working, which probably comes as no surprise to you all.
But to get me started, I would like to have a simple example that works. Any example would do.
Hope anyone can help me out with this.
Thanks very much, best, Marco.
=====
declare variable $data := collection(PRODRMCollectionItems); declare variable $output := 'C:\DATAQUERY\BaseX\Q001\outputPROD';
(:This is where all the work is happening:) declare function local:process-data ($nodes as item()*) as element (root) { <RMCollectionItemsDATA created="{current-dateTime()}"> { for $a in $nodes//artObjectGetResponse/artObject[objectNumber eq 'NG-NM-1395-A'] return <item>{$a}</item> } </RMCollectionItemsDATA> };
(:here we store stuff:) let $filename := concat($output, "marco.xml") return file:write($filename, local:process-data($data)) =====
participants (4)
-
Andy Bunce -
Bridger Dyson-Smith -
Graydon Saunders -
Marco Roling