28
Copyright © 2010 Open Geospatial Consortium, Inc. All Rights Reserved.
9.2 Changes from compliance level SF-0
9.2.1 Basic data types
In additions to the basic data types listed in sub-clause 8.4.4, schemas that comply with compliance level SF-1 of this profile also allow:
a User defined types composed of elements with spatial and non-spatial scalar types as defined in this profile
Clause 9.3.2 describes how user defined types shall be declared in application schemas that comply with level SF-1.
9.2.2 Cardinality
The maximum cardinality that can be declared in an application schema that complies with level SF-0 is 1. This means that the attribute minOccurs can have values of 0 or 1
and the attribute maxOccurs can only have the value of 1.
This restriction is relaxed for application schemas that comply with level SF-1 of this profile. The attribute minOccurs can have a value of 0 or N, where N is a non-negative
integer greater than zero. The attribute maxOccurs can have a value of 0, N or unbounded, where N is a non-negative integer greater than zero and the special value
unbounded is used to indicate that the element may recur an unlimited number of times in an instance document.
In the XML schemas fragments presented as templates in clause 8, all instance of
minOccurs=0|1
shall be replaced by
minOccurs=0|N
and all instances of
maxOccurs=1
shall be replaced by
maxOccurs=0|N|unbounded
for compliance level SF-1.
9.2.3 Multiplicity
For compliance level SF-1, the attributes minOccurs and maxOccurs can have the values 0, any positive integer N or the string unbounded.
9.2.4 Null values
Unlike compliance level SF-0, level SF-1 allows the use of the nillable attribute when declaring elements in an application schema.
Table 8, which is similar to Table 5 in clause 8.4.4.4, summarizes how the various combinations of minOccurs, maxOccurs, nillable, an elements content and the nil
attribute are interpreted to set the value of a feature property for GML application schemas that comply with level SF-1. The table takes into account the fact that elements
can have a maximum cardinality that is greater than 1.