MarkLogic 12 Product Documentationxdmp:eval
xdmp:eval( $xquery as xs:string, [$vars as item()* | map:map], [$options as (element()|map:map)?] ) as item()*
Summary
Returns the result of evaluating a string as an XQuery module. To evaluate JavaScript, see xdmp:javascript-eval.
| Parameters | |
|---|---|
| $xquery | A string containing the XQuery code to be evaluated. If the string contains double quotes ("), surround the string with single quotes ('). |
| $vars |
External variable values to make available to the evaluated code,
expressed as either a sequence of alternating QName-value pairs, or
a map:map. If you use a sequence, it must contain
alternating variable QNames and values. e.g.
(xs:QName("var1"), "val1", xs:Qname("var2"), "val2").
If you use a map, then each key is a string representing the Clark
notation of the variable QName ("{namespaceURI}localname"), and its
value is the corresponding variable value. You can use
xdmp:key-from-QName
to generate the Clark notation to use as a key.
|
| options |
Options with which to customize this operation.
You can specify options as either an options XML element
in the namespace "xdmp:eval", or as a map:map. The
option names below are XML localnames. When using a map, replace any
hyphens in an option name with camel casing. For example, "an-option"
becomes "anOption" when used as a map:map entry key.
This function supports the following options:
|
Required Privileges
To use this function, you must have the following privilege:http://marklogic.com/xdmp/privileges/xdmp-eval
To use the database option to specify a content database
other than the default database for the current App Server, you must
have the following privilege:
http://marklogic.com/xdmp/privileges/xdmp-eval-in
To use the modules or root options to specify
to specify a modules database or root other than that configured for the
current App Server, you must have the following privilege:
http://marklogic.com/xdmp/privileges/xdmp-eval-modules-change
To use the modules or root options to specify
to specify using the file system as the modules database or root path, you
you must have the following privilege:
http://marklogic.com/xdmp/privileges/xdmp-eval-modules-change-file
To use the user-id
option, you must have the
following privilege:
http://marklogic.com/xdmp/privileges/xdmp-login
To use the timestamp option, you must have the following
privileges:
http://marklogic.com/xdmp/privileges/xdmp-timestamp
Usage Notes
To get the database ID for options that require one, such as
the database or modules options, you can use
functions such as the following. Use the function appropriate to the
database you want to reference.
See Also
-
For synchronous evaluation of an an in-memory block of
JavaScriptcode, see xdmp:javascript-eval - For synchronous module invocation, see xdmp:invoke
- For asynchronous module invocation, see xdmp:spawn
- Understanding Transactions in MarkLogic Server
Example
xdmp:eval("1+1")
=> 2
Example
xquery version "1.0-ml";
declare namespace my='http://mycompany.com/test';
let $s :=
"xquery version '1.0-ml';
declare namespace my='http://mycompany.com/test';
declare variable $my:x as xs:string external;
declare variable $my:y as xs:string external := 'goodbye';
concat('hello ', $my:x, ' ', $my:y)"
return
(: evaluate the query string $s using the variables
supplied as the second parameter to xdmp:eval :)
xdmp:eval($s, (xs:QName("my:x"), "world"))
=> hello world goodbye
(the "goodbye" comes from the default value specified for $my:y)
Example
xdmp:eval("doc('/docs/mydoc.xml')", (),
<options xmlns="xdmp:eval">
<database>{xdmp:database("otherdb")}</database>
</options>)
=> The '/docs/mydoc.xml' document from the
otherdb database.
Example
Stack Overflow: Get the most useful answers to questions from the MarkLogic community, or ask your own question.