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{{Mark|Updated with Version 8.5:}} <code>base-uri</code> option added.
|}
==xquery:fork-join==
{{Mark|Introduced with Version 8.5}}:
{| width='100%'
|-
| width='120' | '''Signatures'''
|{{Func|xquery:fork-join|$functions as function(*)*|item()*}}
|-
|'''Summary'''
|This function executes the supplied (non-updating) functions in parallel.<br/>Parallel query execution is recommendable if you have various calls that require a lot of time, but cannot be sped up by rewriting the code. This is e. g. the case if external URLs are called. If you are parallelizing local data reads (such as accessing a database), your single-threaded query will usually be faster, because parallelized access to disk data will often lead to randomized access patterns, which can hardly be optimized by your HD or SSD.
|-
| '''Examples'''
|
* The following function sleeps in parallel; it will be finished in 1 second if your system has at least 2 cores:
<pre class='brush:xquery'>
let $f := function() { prof:sleep(1000) }
return xquery:fork-join(($f, $f))
</pre>
* In the following query, up to four URLs will be requested in parallel:
<pre class='brush:xquery'>
let $funcs :=
for $segment in 1 to 4
let $url := 'http://url.com/path' || $segment
return function() { http:send-request((), $url) }
return xquery:fork-join($funcs)
</pre>
|-
|'''Errors'''
|{{Error|BXXQ0006|#Errors}} an unexpected error occurred.
{{Mark|Updated with Version 8.5}}: Relative URIs will always be resolved against the static base URI of the query.
{{Mark|Updated with Version 8.5}}: Relative URIs will always be resolved against the static base URI of the query.
no edit summary
==xquery:eval==
{| width='100%'
|-
| width='120' | '''Signatures'''
|{{Func|xquery:eval|$query as xs:string|item()*}}<br />{{Func|xquery:eval|$query as xs:string, $bindings as map(*)?|item()*}}<br />{{Func|xquery:eval|$query as xs:string, $bindings as map(*)?, $options as map(xs:string, xs:string)|item()*}}<br />
|-
| '''Summary'''
* {{Code|permission}}: the query will be evaluated with the specified permissions (see [[User Management]]).
* {{Code|timeout}}: query execution will be interrupted after the specified number of seconds.
* {{Code|memory}}: query execution will be interrupted if the specified number of megabytes will be exceeded. This check works best if only one process is running at the same time. Moreover, please note that this option enforces garbage collection, so it will take some additional time, and it requires GC to be enabled in your JVM.* {{Code|base-uri}}: set [https://www.w3.org/TR/xquery-31/#dt-static-base-uri base-uri property] for the query. This URI will be used when resolving relative URIs by functions such as {{Code|fn:doc}}. Added with {{Version|8.5}}.
|-
| '''Errors'''
|-
| width='120' | '''Signatures'''
|{{Func|xquery:update|$query as xs:string|item()*}}<br />{{Func|xquery:update|$query as xs:string, $bindings as map(*)?|item()*}}<br />{{Func|xquery:update|$query as xs:string, $bindings as map(*)?, $options as map(xs:string, xs:string)|item()}}<br />
|-
| '''Summary'''
| '''Errors'''
|{{Error|BXXQ0002|#Errors}} the query contains no [[XQuery Update#Updating Expressions|updating expressions]].<br/>{{Error|BXXQ0003|#Errors}} insufficient permissions for evaluating the query.<br/>{{Error|BXXQ0004|#Errors}} query execution exceeded timeout or memory limit.<br/>{{Error|BXXQ0005|#Errors}} nested query evaluation is not allowed.<br/>Any other error that may occur while evaluating the query.
|}
==xquery:parse-uri==
{| width='100%'
==xquery:invoke==
{| width='100%'
|-
| width='120' | '''Signatures'''
|{{Func|xquery:invoke|$uri as xs:string|item()*}}<br />{{Func|xquery:invoke|$uri as xs:string, $bindings as map(*)?|item()*}}<br />{{Func|xquery:invoke|$uri as xs:string, $bindings as map(*)?, $options as map(*)|item()*}}<br />
|-
| '''Summary'''
| '''Errors'''
|{{Error|BXXQ0001|#Errors}} the expression contains [[XQuery Update#Updating Expressions|updating expressions]].<br/>{{Error|BXXQ0003|#Errors}} insufficient permissions for evaluating the query.<br/>{{Error|BXXQ0004|#Errors}} query execution exceeded timeout.<br/>{{Error|BXXQ0005|#Errors}} nested query evaluation is not allowed.<br/>Any other error that may occur while evaluating the query.
|}
=Parallelized Execution=
Parallel query execution is recommendable if you have various calls that require a lot of time, but cannot be sped up by rewriting the code. This is e. g. the case if external URLs are called. If you are parallelizing local data reads (such as the access to a database), single-threaded queries will usually be faster, because parallelized access to disk data often results in randomized access patterns, which can hardly be optimized by the caching strategies of HD, SSD or operating system.
==xquery:fork-join==
{| width='100%'
|-
| width='120' | '''Signatures'''
|{{Func|xquery:fork-join|$functions as function(*)*|item()*}}
|-
|'''Summary'''
|This function executes the supplied (non-updating) functions in parallel.
|-
| '''Examples'''
|
* The following function sleeps in parallel; it will be finished in 1 second if your system has at least 2 cores:
<pre class='brush:xquery'>
let $f := function() { prof:sleep(1000) }
return xquery:fork-join(($f, $f))
</pre>
* In the following query, up to four URLs will be requested in parallel:
<pre class='brush:xquery'>
let $funcs :=
for $segment in 1 to 4
let $url := 'http://url.com/path' || $segment
return function() { http:send-request((), $url) }
return xquery:fork-join($funcs)
</pre>
|-
|'''Errors'''
|{{Error|BXXQ0006|#Errors}} an unexpected error occurred.
|}
