1. THE DATATYPES OF XML SCHEMA A Practical Introduction
John Cowan
Reuters Health Information

2. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Licensed under the GNU General Public License
ABSOLUTELY NO WARRANTIES; USE AT YOUR OWN RISK
Black and white for readability
11/29/2018
Copyright John Cowan 2001, 2002; licensed under GNU GPL

3. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Abstract
This is a brief description, useful for RELAX NG and XML Schema users, of the simple datatypes of XML Schema and their associated facets. A brief summary of XML Schema regular expression language is also given.
11/29/2018
Copyright John Cowan 2001, 2002; licensed under GNU GPL

4. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Roadmap
Types (11 slides)
Facets (7 slides)
Regular expression language (6 slides)
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

5. Copyright John Cowan 2001, 2002; licensed under GNU GPL
XML Schema Datatypes
A type is a named set of values
An XML Schema datatype provides a standardized, machine-checkable representation of a type
XML Schema types can be grouped:
numeric, date, boolean, string, misc.
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

6. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Numeric Types
Decimal types
Floating-point types
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

7. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Decimal Types
decimal
integer
nonPositiveInteger
negativeInteger
nonNegativeInteger
positiveInteger
unsigned{Long, Int, Short, Byte}
long, int, short, byte
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

8. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Decimal Types
long, short, int, and byte are the same as in Java: 64, 32, 16, 8 bits
unsignedLong, unsignedShort, unsignedInt, and unsignedByte are the obvious unsigned analogues
All other numeric types are unbounded
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

9. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Floating-point Types
Only two floating-point types
float
double
IEEE ranges (same as Java, all modern hardware)
11/29/2018
Copyright John Cowan 2001, 2002; licensed under GNU GPL

10. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Date Types
duration
date, time, dateTime
gYear, gMonth, gDay, gYearMonth, gMonthDay
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

11. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Date Types
Duration
duration
Single Time Interval
dateTime, date, gYear, gYearMonth
Recurring Time Interval
time, gMonth, gDay, gMonthDay
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12. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Date Type Examples
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

13. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Boolean Type
Only two values are legal:
true (which can also be written 1)
false (which can also be written 0)
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

14. Copyright John Cowan 2001, 2002; licensed under GNU GPL
String Types
string
normalizedString
token
language
NMTOKEN(S)
Name
NCName
o ID, IDREF(S), ENTITY(IES)
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15. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Miscellaneous Types
Raw octet types
hexBinary
base64Binary
anyURI
QName
NOTATION
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

16. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Facets
Allow the creation of new datatypes by restricting the existing ones in one or more ways
Called params in RELAX NG
Facets can be grouped into families applicable to datatype families:
length, value, pattern
enumeration, whiteSpace
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

17. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Length Facets
Applicable to string and miscellaneous types
length facet gives exact length
minLength and maxLength facets set limits; either or both may be used
lengths of hexBinary and base64Binary types are measured in octets, not characters
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

18. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Value Facets
Applicable to numeric and date types
minExclusive and minInclusive specify a lower bound; either but not both may be used
maxExclusive and maxInclusive specify an upper bound; either but not both may be used
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

19. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Value Facets
totalDigits specifies the total number of significant digits in a decimal, integer, (non)PositiveInteger, or (non)NegativeInteger value
fractionDigits specifies the number of fractional digits in a decimal value
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

20. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Pattern Facet
Applicable to any type
Specifies a regular expression that the data must match
XML Schema: If multiple pattern facets are present, the data must match at least one of them
RELAX NG: If multiple pattern facets are present, the data must match all of them
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

21. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Enumeration Facet
XML Schema only
Applicable to any type
The instances of the enumeration facet specify individual values
The data must be equal (according to the rules for the type) to one of the specified values
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

22. Copyright John Cowan 2001, 2002; licensed under GNU GPL
whiteSpace Facet
XML Schema only
Applicable to string types
Legal values are:
preserve: leave white space alone
replace: tabs and newlines become spaces
collapse: replace, then remove leading, trailing, and multiple spaces
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

23. XSD Regular Expressions
A subset of Perl regular expressions
Supported constructs:
choice
quantifiers
character classes
parentheses for grouping
All matches are anchored to both ends of the data (so no ^ or $ needed)
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

24. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Choice
abc|def matches either abc or def
Use parentheses to specify the scope of a choice
example: abc(d|e) matches either abcd or abce
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

25. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Quantifiers
(abc){2,4} matches abcabc or or abcabcabc or abcabcabcabc
(abc){2,} matches 2 or more consecutive abc sequences
(abc)* matches 0 or more sequences
(abc)+ matches 1 or more sequences
(abc)? matches 0 or 1 sequences
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

26. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Character Classes
Character classes always match exactly one character, no matter how complex they look
[abc] matches a or b or c
[^abc] matches anything but a or b or c
[a-z] matches any character between a and z inclusive
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

27. Single-Letter Classes
\n, \r, \t - newline, return, tab
. - anything but newline or return
\s, \S - whitespace, non-whitespace
\i, \I - name initial, non-name initial
\c, \C - name char, non-name char
\d, \D - decimal digit, non-decimal digit
\w, \W - word char, non-word char
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Copyright John Cowan 2001, 2002; licensed under GNU GPL

28. Copyright John Cowan 2001, 2002; licensed under GNU GPL
Unicode Classes
\p{Xx}, \P{Xx} - matches anything in (not in) a Unicode General Category
example: \p{Ll} matches lower case
\p{IsXxxxxx}, \P{IsXxxxx} - matches anything in (not in) a Unicode block
example: \P{IsCyrillic} matches any non-Cyrillic character
11/29/2018
Copyright John Cowan 2001, 2002; licensed under GNU GPL