xml and databases exercise session 3 (courtesy of ghislain fourny/eth)

XML and DatabasesExercise Session 3

(courtesy of Ghislain Fourny/ETH)

Department of Computer Science

Good to know: XML Schema types

Simple type - predefined or user-defined - element or attribute type

Complex type - user-defined - element type only

Empty content Simple content Complex content Mixed content

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Types (can) have QNames: All predefined types

User-defined types (here simple)

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Tags, attributes... XML Schema looks like XML... that's because it is XML!

Tags, attributes... XML Schema looks like XML... that's because it is XML!



They can also be anonymous.

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Anonymous types can be defined under any xs:element or xs:attribute. Non-anonymous types have a global scope and must be defined directly under xs:schema.

Anonymous types can be defined under any xs:element or xs:attribute. Non-anonymous types have a global scope and must be defined directly under xs:schema.


Complex types in XML Schema

Complex type, complex content

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Simple content (here anonymous)

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Empty content Simple content restricted to "" Or a complex content without any children

Mixed content As in complex content, with an additional attribute

mixed set to true in xs:complexType

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Exercises 1-3

Passenger

Flight

Airport

Booking

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Exercises 1-3

Passenger: name, address, passport number

Flight: ID, number of seats, date, origin, dest

Airport: name, code, tax value

Booking: credit card, flight, passenger

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Exercise 1: XML Data

Sample data

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How to prevent this?

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How to prevent this?

With a DTD/Schema!

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Exercise 2: XML Schema Modelling

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Passport number name address

Passenger



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code name tax


Airport

Passenger



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code name tax flightID seatNo date


Airport Flight

Passenger



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Airport Flight

Passenger

source

dest



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credit card


Airport Flight

Passenger

source

dest

book



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credit card


Airport Flight

Passenger

source

dest

book

1

1

N

N

N

M


Exercise 2: What‘s wrong?

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Exercise 2: Inconsistency

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Exercise 2: Inconsistency

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Exercise 2: Redundancy

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Exercise 2: Redundancy

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Exercise 2: Extraneous data

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Exercise 2: A Schema for Passenger

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Passenger


Exercise 2: A Schema for Passenger

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Passenger


Exercise 2: A Schema for Flight

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flightID seatNo date

Airport Flight

source

dest



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Airport Flight

source

dest



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Airport Flight

source

dest



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Airport Flight

source

dest


Exercise 2: A Schema for Airport

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code name tax

Airport



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code name tax

Airport



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code name tax

Airport


Exercise 2: Root Element

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Exercise 3: DTD and XML Schema

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Exercise 3: Corresponding XML Schema

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Department of Computer Science 42

Hope to see you next week!Hope to see you next week!

xml and databases exercise session 3 (courtesy of ghislain fourny/eth)

Documents

tax airport slide

address passenger slide

xml schema modelling

corresponding xml schema

xml schema types types

xml schema simple content

xml schema complex type

passenger flight airport