XQuery用条件失败替换值

Question

i am in the middle of creating xquery replace-value of node action in XQuery .

But seems this code is not working therefore the IF-ELSE statement is always going to else.

This is my code:

declare function local:replacing($contextData as element()) 
as element()*
{    
    copy $pipeline := $contextData/Handler/Data/*

     modify(

   if(not(empty(data($pipeline/Payload/sample/transactionType)))) then 
     replace value of node $pipeline/Payload/sample/transactionType with 'XXX' else (),
   if(not(empty(data($pipeline/Payload/sample/revision)))) then
     replace value of node $pipeline/Payload/sample/revision with 'XXX' else ()

      )
 return $pipeline
 };

I try against this sample XML but the result is always not XXX when the field revision is having value. (this always goes to else statement)

let $result :=
<root>
<Handler>
  <Data>
    <root>

      <Payload>
            <sample>
            <transactionType></transactionType>
            <revision>123</revision>
            <board>1</board>
            <mission>1</mission>
            <method>Manual</method>
            <listOfBoard>
              <board>
                <type>small</type>
                <amount>5054</amount>
                <token>300</token>
              </board>
            </listOfBoard>
            <pricing>300</pricing>
            <playing>Wed</playing>
          </sample>   
    </Payload>

    </root>

  </Data>
</Handler>
</root>

Current Result:

<root>
  <Payload>
    <sample>
      <transactionType/>
      <revision>123</revision>
      <board>1</board>
      <mission>1</mission>
      <method>Manual</method>
      <listOfBoard>
        <board>
          <type>small</type>
          <amount>5054</amount>
          <token>300</token>
        </board>
      </listOfBoard>
      <pricing>300</pricing>
      <playing>Wed</playing>
    </sample>
  </Payload>
</root>

Expected Result

<root>
      <Payload>
        <sample>
          <transactionType/>
          <revision>XXX</revision>
          <board>1</board>
          <mission>1</mission>
          <method>Manual</method>
          <listOfBoard>
            <board>
              <type>small</type>
              <amount>5054</amount>
              <token>300</token>
            </board>
          </listOfBoard>
          <pricing>300</pricing>
          <playing>Wed</playing>
        </sample>
      </Payload>
    </root>

Any ideas for this?

Update

As recommended by Har below, i change the code into:

 if(not(empty(data($pipeline/Payload/sample/transactionType)))) then 
             replace value of node $pipeline/Payload/sample/transactionType with 'XXX'
         else (
            if(not(empty(data($pipeline/Payload/sample/revision)))) then
            replace value of node $pipeline/Payload/sample/revision with 'XXX' else ()
         )

But seems the result is the same. It still goes to else () statement. Any ideas?

Thank you before.

Answer 1

The problem was, empty() checks for empty sequence, so sequence containing one empty string is considered true by empty() . You can just pass data() result to if since empty has Effective Boolean Value of false :

if(data($pipeline/Payload/sample/transactionType)) then 
    replace value of node $pipeline/Payload/sample/transactionType with 'XXX' else (),
if(data($pipeline/Payload/sample/revision)) then
    replace value of node $pipeline/Payload/sample/revision with 'XXX' else ()