In the remainder of this appendix, we use the following simple library application, adapted from our first example in Chapter 1 to illustrate the use of the various schema languages:
<library>
<book id="-0836217462">
<isbn>
0836217462
</isbn>
<title>
Being a Dog Is a Full-Time Job
</title>
<author-ref id="Charles-M.-Schulz"/>
<character-ref id="Peppermint-Patty"/>
<character-ref id="Snoopy"/>
<character-ref id="Schroeder"/>
<character-ref id="Lucy"/>
</book>
<book id="-0805033106">
<isbn>
0805033106
</isbn>
<title>
Peanuts Every Sunday
</title>
<author-ref id="Charles-M.-Schulz"/>
<character-ref id="Sally-Brown"/>
<character-ref id="Snoopy"/>
<character-ref id="Linus"/>
<character-ref id="Snoopy"/>
</book>
<author id="Charles-M.-Schulz">
<name>
Charles M. Schulz
</name>
<nickName>
SPARKY
</nickName>
<born>
November 26, 1922
</born>
<dead>
February 12, 2000
</dead>
</author>
<character id="Peppermint-Patty">
<name>
Peppermint Patty
</name>
<since>
Aug. 22, 1966
</since>
<qualification>
bold, brash and tomboyish
</qualification>
</character>
<character id="Snoopy">
<name>
Snoopy
</name>
<since>
October 4, 1950
</since>
<qualification>
extroverted beagle
</qualification>
</character>
<character id="Schroeder">
<name>
Schroeder
</name>
<since>
May 30, 1951
</since>
<qualification>
brought classical music to the Peanuts strip
</qualification>
</character>
<character id="Lucy">
<name>
Lucy
</name>
<since>
March 3, 1952
</since>
<qualification>
bossy, crabby and selfish
</qualification>
</character>
<character id="Sally-Brown">
<name>
Sally Brown
</name>
<since>
Aug, 22, 1960
</since>
<qualification>
always looks for the easy way out
</qualification>
</character>
<character id="Linus">
<name>
Linus
</name>
<since>
Sept. 19, 1952
</since>
<qualification>
the intellectual of the gang
</qualification>
</character>
</library>