XQuery concat to the same variable-CodePudding

Simple code there-

let $sV2 :=''
for $i in (1 to 2)
    let $sV1 := 'test1'
    let $sV2 := if (fn:string-length($sV2) != 0) then fn:concat($sV2,'||',$sV1) else ($sV1)
     return
     <test>{$sV2}</test>

i get the same output

<test>test1</test>
<test>test1</test>

whereas i expect

<test>test1</test>
<test>test1||test1</test>

what am i doing wrong? i tried to debug but why does V2 initialize to null/'' for second iteration.

Note- I have to use xquery 1.0 do to some product limitations.

How do i get the expected output?

CodePudding user response：

XQuery is a functional language. As such, it does not allow you to change the value of a variable once it has been assigned.

There are many other ways to reach the same results, though. Your specific query can e.g. be rewritten as follows:

for $i in 1 to 2
return <test>{
  string-join(for $n in 1 to $i return 'test1', '||')
}</test>