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Examples

The following XQuery expressions extract information from the recipe collection:

"The titles of all recipes": 
for $t in document("recipes.xml")//title
return $t

<title>Beef Parmesan with Garlic Angel Hair Pasta</title>,
<title>Ricotta Pie</title>,   
<title>Linguine Pescadoro</title>,   
<title>Zuppa Inglese</title>,   
<title>Cailles en Sarcophages</title>

"The dishes that contain flour": 
<floury>
  { for $r in document("recipes.xml")//recipe[.//ingredient[@name="flour"]]
    return <dish>{$r/title/text()}</dish>
  }
</floury>

<floury>   
  <dish>Ricotta Pie</dish>   
  <dish>Zuppa Inglese</dish>   
  <dish>Cailles en Sarcophages</dish> 
</floury>

"For each ingredient, the recipes that it is used in": 
for $i in distinct-values(document("recipes.xml")//ingredient/@name)
return <ingredient name="{$i}">
             { for $r in document("recipes.xml")//recipe
               where $r//ingredient[@name=$i]
               return $r/title
             }
       </ingredient>

<ingredient name="beef cube steak">
  <title>Beef Parmesan with Garlic Angel Hair Pasta</title>   
</ingredient>,   
<ingredient name="onion, sliced into thin rings">
  <title>Beef Parmesan with Garlic Angel Hair Pasta</title>   
</ingredient>,   
  ...
<ingredient name="butter">
  <title>Beef Parmesan with Garlic Angel Hair Pasta</title>
  <title>Cailles en Sarcophages</title>
</ingredient>,
  ...

"The recipes that use some of the stuff in our refrigerator": 
distinct-values(
  for $r in document("recipes.xml")//recipe
  for $i in $r//ingredient/@name
  for $j in document("fridge.xml")//stuff[text()=$i]
  return $r/title
)

<title>Beef Parmesan with Garlic Angel Hair Pasta</title>,
<title>Ricotta Pie</title>,
<title>Linguine Pescadoro</title>,

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