XML/XQuery/order by

Inadvertent resorting in document inventory

   <source lang="xml">

File: Data.xml <order>

 <car model="A">
   <id>0001</id>
   <name language="en">name 1</name>
   <colorChoices>navy black</colorChoices>
 </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>
 <car model="C">
   <id>0004</id>
   <name language="en">name 4</name>
 </car>

</order> File: Query.xquery let $sortedProds := for $prod in doc("Data.xml")//car

                   order by $prod/id
                   return $prod

for $prodName in $sortedProds/name

return

{string($prodName)}

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

name 1

name 2

name 3

name 4

</source>
   
  

order by clause demo

   <source lang="xml">

File: Data.xml <order>

 <car model="A">
   <name language="en">name 1</name>
 </car>
 <car model="B">
   <name language="en">name 2</name>
 </car>
 <car model="B">
   <name language="en">name 3</name>
 </car>

</order>

File: Query.xquery for $prod in doc("Data.xml")/order/car where $prod/@model = "B" order by $prod/name return $prod/name Output: <?xml version="1.0" encoding="UTF-8"?> <name language="en">name 2</name> <name language="en">name 3</name>

</source>
   
  

order by stateCt

   <source lang="xml">

File: Data.xml

<order>

 <car dept="A">
   <number>1</number>
   <name language="en">name 1</name>
 </car>
 <car dept="B">
   <number>2</number>
   <name language="en">name 2</name>
 </car>
 <car dept="B">
   <number>3</number>
   <name language="en">name 3</name>
 </car>
 <car dept="C">
   <number>4</number>
   <name language="en">name 4</name>
 </car>

</order>

File: Query.xquery

for $prod in doc("Data.xml")//car where $prod/@dept = "B" order by $prod/name return $prod/name

Output: <?xml version="1.0" encoding="UTF-8"?> <name language="en">name 2</name> <name language="en">name 3</name>

</source>
   
  

The order by clause

   <source lang="xml">

File: Data.xml <inventory>

 <car model="A" id="0001" />
 <car model="B" id="0002" />
 <car model="B" id="0003" />
 <car model="C" id="0004" />
 <car model="C" id="0004" />
 <car model="A" id="0001" />

</inventory>

File: Query.xquery for $car in doc("Data.xml")//car order by $car/@id return $car Output: <?xml version="1.0" encoding="UTF-8"?> <car model="A" id="0001"/> <car model="A" id="0001"/> <car model="B" id="0002"/> <car model="B" id="0003"/> <car model="C" id="0004"/> <car model="C" id="0004"/>

</source>
   
  

Using an inventory comparison

   <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 for $prod in $prods where $prod << $prods[@model = $prod/@model][last()] return $prod

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

   <id>0002</id>
   <name language="en">name 2</name>
 </car>
</source>
   
  

Using multiple inventorying specifications

   <source lang="xml">

File: Data.xml <inventory>

 <car model="A" id="0001"/>
 <car model="B" id="0002"/>
 <car model="B" id="0003"/>
 <car model="C" id="0004"/>
 <car model="C" id="0004"/>
 <car model="A" id="0001"/>

</inventory>

File: Query.xquery

for $car in doc("Data.xml")//car order by $car/@model, $car/@id return $car Output: <?xml version="1.0" encoding="UTF-8"?> <car model="A" id="0001"/> <car model="A" id="0001"/> <car model="B" id="0002"/> <car model="B" id="0003"/> <car model="C" id="0004"/> <car model="C" id="0004"/>

</source>
   
  

without inadvertent resorting

   <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>
 <car model="C">
   <id>0004</id>
   <name language="en">name 4</name>
 </car>

</order> File: Query.xquery for $prod in doc("Data.xml")//car order by $prod/id

return

{string($prod/name)}

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

name 1

name 2

name 3

name 4

</source>