XML/XQuery/if

Conditional expression

   <source lang="xml">

File: Data.xml <order>

 <car model="A">
   <id>0001</id>
   <name language="en">name 1</name>
 </car>
 <car model="B">
   <id>0002</id>
   <name language="en">name 2</name>
 </car>
 <car model="B">
   <id>0003</id>
   <name language="en">name 3</name>
 </car>

</order> File: Query.xquery for $prod in (doc("Data.xml")/order/car) return if ($prod/@model = "ACC")

      then <accessoryid>{data($prod/id)}</accessoryid>
      else <otherid>{data($prod/id)}</otherid>

Output: <?xml version="1.0" encoding="UTF-8"?> <otherid>0001</otherid> <otherid>0002</otherid> <otherid>0003</otherid>

</source>
   
  

Conditional expression returning multiple expressions

   <source lang="xml">

File: Data.xml <order>

 <car model="ACC">
   <id>0001</id>
   <name language="en">name 1</name>
   <colorChoices>navy black</colorChoices>
 </car>
 <car model="BCC">
   <id>0002</id>
   <name language="en">name 2</name>
 </car>
 <car model="BCC">
   <id>0003</id>
   <name language="en">name 3</name>
 </car>

</order> File: Query.xquery for $prod in (doc("Data.xml")/order/car) return if ($prod/@model = "ACC")

      then (<accessoryid>{data($prod/id)}</accessoryid>,
           <accessoryName>{data($prod/name)}</accessoryName>)
      else <otherid>{data($prod/id)}</otherid>

Output: <?xml version="1.0" encoding="UTF-8"?> <accessoryid>0001</accessoryid> <accessoryName>name 1</accessoryName> <otherid>0002</otherid> <otherid>0003</otherid>

</source>
   
  

Converting values without a lookup table

   <source lang="xml">

File: Data.xml <order>

 <car model="A">
   <id>0001</id>
   <name language="en">name 1</name>
 </car>
 <car model="B">
   <id>0002</id>
   <name language="en">name 2</name>
 </car>
 <car model="B">
   <id>0003</id>
   <name language="en">name 3</name>
 </car>

</order> File: Query.xquery let $cat := doc("Data.xml")/order for $model in distinct-values($cat/car/@model)

return

Department: {if ($model = "B") then "Accessories" else if ($model = "C") then "Menswear" else if ($model = "A") then "Womens" else () } ({$model})

Output: <?xml version="1.0" encoding="UTF-8"?>

Department: Womens (A)

Department: Accessories (B)

</source>
   
  

If statement in return clause

   <source lang="xml">

File: Data.xml

<order>

 <car model="A">
   <id>0001</id>
   <name language="en">name 1</name>
 </car>
 <car model="B">
   <id>0002</id>
   <name language="en">name 2</name>
 </car>
 <car model="B">
   <id>0003</id>
   <name language="en">name 3</name>
 </car>

</order>

File: Query.xquery let $prods := doc("Data.xml")//car

    let $idProds := count($prods)
    for $prod at $count in $prods
    return if ($count = $idProds)
           then concat($prod/name,".")
           else concat($prod/name,",")

Output: <?xml version="1.0" encoding="UTF-8"?>name 1, name 2, name 3.

</source>
   
  

If then else stateCt

   <source lang="xml">

File: Data.xml <prices>

 <priceList effDate="2006-11-15">
   <prod num="1">
     <price currency="USD">29.99</price>
     <discount type="CLR">10.00</discount>
   </prod>
   <prod num="2">
     <price currency="USD">69.99</price>
   </prod>
   <prod num="3">
     <price currency="USD">39.99</price>
     <discount type="CLR">3.99</discount>
   </prod>
 </priceList>

</prices>

File: Query.xquery

let $bargains := doc("Data.xml")/prices/priceList/prod[price < 30] return if ($bargains)

      then <bargain-bin>{$bargains}</bargain-bin>
      else ()

Output: <?xml version="1.0" encoding="UTF-8"?> <bargain-bin>

  <prod num="1">
     <price currency="USD">29.99</price>
     <discount type="CLR">10.00</discount>
   </prod>

</bargain-bin>

</source>
   
  

Nested conditional expressions

   <source lang="xml">

File: Data.xml <order>

 <car model="ACC">
   <id>0001</id>
   <name language="en">name 1</name>
 </car>
 <car model="BCC">
   <id>0002</id>
   <name language="en">name 2</name>
 </car>
 <car model="BCC">
   <id>0003</id>
   <name language="en">name 3</name>
 </car>

</order>

File: Query.xquery for $prod in (doc("Data.xml")/order/car) return if ($prod/@model = "ACC")

      then <accessory>{data($prod/id)}</accessory>
      else if ($prod/@model = "WMN")
           then <womens>{data($prod/id)}</womens>
           else if ($prod/@model = "MEN")
                then <mens>{data($prod/id)}</mens>
                else <other>{data($prod/id)}</other>

Output: <?xml version="1.0" encoding="UTF-8"?> <accessory>0001</accessory> <other>0002</other> <other>0003</other>

</source>