Shared properties KVP encoding

Copyright © 2010 Open Geospatial Consortium 41 SortBy + sortProperty [1. .] : SortProperty from ISO 19143 Filter Encoding SortOrder + ascending + descending from ISO 19143 Filter Encoding Enumeration SortProperty + valueReference : ValueReference + sort Order : SortOrder from ISO 19143 Filter Encoding Figure 10 — Query sorting clause 7.9.2.5.4.2 XML encoding In XML, the sorting clause of an ad hoc query expression shall be encoded using the fes:SortBy element see ISO 19143:2010, Clause 8. An ad hoc query expression shall have a minimum of zero and a maximum of one fes:SortBy child elements.

7.9.2.5.4.3 KVP encoding

For KVP-encoded request, the sorting clause shall be encoded using the keyword SORTBY keyword see ISO 19143:2010, Table 2.

7.9.2.5.4.4 Sort processing

A web feature service that receives an ad hoc query expression without a sorting clause, shall generate a response document in which features are presented in whatever order the server chooses. However, to comply with this International Standard, servers shall ensure that whatever order is presented when an ad hoc query, not containing a sort clause, is first executed is preserved across subsequent executions of the same ad hoc query expression on the same set of features. EXAMPLE A server may choose to sort the features by their gml:id if the client has not specified a specific sorting clause. Subsequent invocations of the same query expression on the same set of data should result in a response document that presents the features in the same order. In the event that a web feature service receives a request containing an ad hoc query with a sorting clause, the service shall respond by presenting features in the response document in the requested order. Sorting is only supported within the scope of a single ad hoc query expression. Global sorting over all features in a result set, generated by multiple ad hoc query expressions being encoded in the request, shall not be supported. The trivial exception to this statement, of course, is the case where the request contains a single query expression. When processing a query with a sorting clause, the sort shall be executed in the context of all the data that matches the request parameters before the response is possibly reduced to a set within the limits of the count attribute see 7.6.3.5.