integer data type
The xs:integer data type represents a number that is less than or equal to 9 223 372 036 854 775 807 and greater than or equal to -9 223 372 036 854 775 808. Derived from xs:decimal data type.
The lexical form of xs:integer is a finite-length sequence
of decimal digits with an optional leading sign. If the sign is omitted,
a positive sign (+) is assumed. The following numbers are valid examples
of this data type: -1, 0, 12678967543233, and +100000.