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The {{Code|update}} expression is a convenience operator for the {{Code|copy/modify/return}} construct.Similar to the [[XQuery 3.0#Simple Map Operator|XQuery 3.0 map operator]], the value of the firstexpression is bound as context item, and the second expression performs updates on this item.The updated item is returned as result. With {{Version|8.5}}, the update expression was extended: * In analogy with [[#transform with|transform with]], the updating expressions can now be – and should be – wrapped with curly braces. * More than one node can now be specified as source:
(<root1root/>, <root2/>) update {
The {{Code|transform with}} expression was added to the current [https<pre class="brush://www.w3.org/TR/xquery-update-30"><xml>text</#id-xml> transform-with XQuery Update 3.0] working draft. It is a simple version { replace value of the [[#update|update]] expression and also available in BaseXnode .with 'new-text'}</pre>
Additional Numerous additional [[Database Module#Updates|database functions]] exist for performing updates on document and database level.
no edit summary
==Non-Updating Expressions==
===transformcopy/modify/return===
<pre class="brush:xquery">
===update===
The {{Code|update}} expression is a BaseX-specific convenience operator for the {{Code|copy/modify/return}}
construct:
* Similar to the [[XQuery 3.0#Simple Map Operator|XQuery 3.0 map operator]], the value of the first
expression is bound as context item, and the second expression performs updates on this item.
The updated item is returned as result:
<pre class="brush:xquery">
</pre>
<pre class="brush:xquery">
db:open('data')//item update { delete node text() }
</pre>
* Update If wrapped with curly braces, update expressions can now be chained:
<pre class="brush:xquery">
insert node <child/> into .
} update {
===transform with===
The {{MarkCode|Introduced transform with Version 8.5}}expression was added to the current [https://www.w3.org/TR/xquery-update-30/#id-transform-with XQuery Update 3.0] working draft. It is a simple version of the [[#update|update]] expression and also availablein BaseX:
==Functions==
===Built-in Functions===
{{Code|fn:put()}} is can be used to serialize XDM instances to secondary storage. It is executed at the end of a snapshot. Serialized documents therefore reflect all changes made effective during a query. No files will be created if the addressed nodes have been deleted. With {{Version|9.0}}, serialization parameters can be specified as third argument (more details are found in the [https://www.w3.org/TR/xquery-update-30/#id-func-put XQUF 3.0 Specification]).
===User-Defined Functions===
to the specification and BaseX. All errors are listed in the
[[XQuery Errors#Update Errors|XQuery Errors]] overview.
Please remember that the collected updates will be executed after the query evaluation.
If errors occur at this final stage, they cannot be caught via try/catch.
=Changelog=
;Version 9.0
* Updated: [[#Built-in Functions|Built-in Functions]]: serialization parameters
;Version 8.5
