XQuery - insert-before Function

The insert-before function is used to insert an item in a given sequence at any position. This function returns the modified sequence but the original sequence is not altered.

Syntax

insert-before($seq as item()*, $position as xs:integer, $inserts as item()*)

Input Parameters

• $seq − provided sequence. Sequence can contain 0 or more items.

• $position − index of item where it is to be inserted. Index starts from 1.

• $inserts − zero or more items to be inserted.

Example

XQuery Expression

let $items := (1,2,3,4,5,9)
let $additional-items := (6,7,8)
let $new-items := insert-before($items,6,$additional-items)
return
   <result>   
      
      <items>
      {
         for $item in $new-items
         return {$item}
      }
      </items>
      
   </result>

Output

<result>
   <items>
      <item>1</item>
      <item>2</item>
      <item>3</item>
      <item>4</item>
      <item>5</item>
      <item>6</item>
      <item>7</item>
      <item>8</item>
      <item>9</item>
   </items>
</result>

Verify the Result

In order to test the above-mentioned functionality, replace the contents of books.xqy (mentioned in Environment Setup chapter) with the above XQuery expression and execute the XQueryTester java program to verify the result.