XML Data Management XPath Exercises: Right or Wrong?

1
XML Data Management XPath Exercises Right or
Wrong?

• Werner Nutt

2
Right or Wrong?

• Return the titles of the recipes that have more
  than 500 calories.
• //recipes/recipe/nutrition_at_caloriesgt500
• /../title
• and what about style?

3
Right or Wrong?

• Return the recipes for which at least 4 eggs are
  needed.
• //recipesum(descendantingredient
• contains(_at_name,"egg")
• /_at_amount) gt 4
• /title

4
Right or Wrong?

• 4. Which recipe has the highest number of
  calories?
• //recipenutrition/_at_calories
• gt precedingnutrition/_at_calories
• and nutrition/_at_calories
• gt followingnutrition/_at_calories

5
Right or Wrong?

• 4. Which recipe has the highest number of
  calories?
• //recipenot(nutrition/_at_calories lt
  precedingrecipe/nutrition/_at_calories)
• and
• not(nutrition/_at_calories lt
  followingrecipe/nutrition/_at_calories)
• what exactly does this query
  return?

6
Right or Wrong?

• 6. How many compound ingredients (i.e.,
  ingredients with ingredients) are there in
  Ricotta Pie?
• count(//recipetitle"Ricotta Pie"
  /ingredient/ingredient/..)
• and what about style?

7
Right or Wrong?

• 8. Which recipes have an ingredient whose
  preparation needs more steps than are needed for
  the recipe itself (i.e., top level steps)?
• //recipecount(ingredient/preparation/step)
  gt
• count(preparation/step)

8
Right or Wrong?

• Return the names of the ingredients of Zuppa
  Inglese.
• //recipetitle"Zuppa Inglese"/ingredient

9
Right or Wrong?

• Which recipes have an ingredient in common with
  Zuppa Inglese?
• //recipetitle!"Zuppa Inglese"
• .//ingredient/_at_name
• //recipetitle"Zuppa Inglese"
• /ingredient/_at_name
  

10
Right or Wrong?

• Return the names of all elementary ingredients
  that occur in at least two recipes.
• //recipe///ingredient
• count(.//ingredient) 0
• and
• (_at_name precedingingredient/_at_na
  me
• or
• _at_name followingingredient/_at_
  name)
• /_at_name

11
Right or Wrong?

• Return the names of all elementary ingredients
  that occur in at least two recipes.
• //recipetitle!precedingtitle
• ingredient/_at_name
• //recipe/ingredient/_at_name
• /ingredient/_at_name

12
Right or Wrong?

• Return the titles of all recipes for which some
  form of egg is needed (like egg whites or egg
  yolk).
• //ingredient_at_namecontains(.,'egg')
• /ancestorrecipe/title
• and what about style?

13
Right or Wrong?

• 17. Return the names of those ingredients that
  are mentioned in a preparation step of their
  recipe.
• //ingredient//preparation/step
  contains(text(),_at_name)

14
Right or Wrong?

• 17. Return the names of those ingredients that
  are mentioned in a preparation step of their
  recipe.
• //ingredientcontains(ancestorrecipe//step,
  _at_name)
• /_at_name

15
Right or Wrong?

• 17. Return the names of those ingredients that
  are mentioned in a preparation step of their
  recipe.
• //ingredientcontains(ancestorrecipe/preparatio
  n, _at_name)
• /_at_name
• Could we write a query that asks for an
  occurrence of the ingredient name
• in any preparation step of the recipe?