LCSC Position Paper on the use of List Containers

[Tim McGrath <tmcgrath@portcomm.com.au>]

Please find attached the documentation provided as preparatory reading 
for the joint LC/NDR call on Tuesday 2nd September.

Due to the overall level of concern about this matter it was felt that a 
real world example would be necessary to identify the strengths and 
weaknesses of implementing these rules and allow an objective debate on 
their value.
Three versions of the current UBL Library were developed and implemented 
in conceptual model, XSD Schema and XML instances.  These were:
a. The current UBL Library with no list container structures
b. The current UBL Library with suitable list container structures 
selectively identified by the LC team
c. The current UBL Library with list container structures for all BIEs 
with potentially multiple occurrences (i.e a cardinality of either 0..n 
or 1..n)

These documents represent the outcome of a test implementation of the 
NDR rules concerning List Containers.

 From this exercise we believe we have been unable to demonstrate any 
pronounced architectural benefits in using List Containers, either in 
processing performance or readability.  Furthermore, even if some easily 
recognized value could be identified for using list containers, these 
would need to outweigh the difficulty of their consistent implementation 
into the UBL library.  We therefore suggest that Rule 116 be 
reconsidered by the UBL NDR team.  

We shall take the opportunity of our upcoming joint call to present this 
paper to the NDR team and would be happy to take questions if required.

The primary document in this set is entitled 
"position-lcsc-listcontainers-02.pdf ".  Also included are:

The UBL Library models used in the test cases:
UBL-Invoice-0.81-draft-8.sxc
UBL-Reusable-0.81-draft-8.sxc
UBL-Invoice-0.81-draft-8-all-lists.sxc
UBL-Reusable-0.81-draft-8-all-lists.sxc

The XSD schemas used:
UBL-Invoice-0.81-draft-8.xsd
UBL-Reusable-0.81-draft-8.xsd
UBL-Reusable-0.81-draft-8-selected-lists.xsd
UBL-Invoice-0.81-draft-8-selected-lists.xsd
UBL-Invoice-0.81-draft-8-all-lists.xsd
UBL-Reusable-0.81-draft-8-all-lists.xsd
- and supported schemas....
UBL-CoreComponentParameters-0.81-draft-8-all-lists.xsd
UBL-CoreComponentParameters-0.81-draft-8.xsd
UBL-CoreComponentTypes-0.81-draft-8-all-lists.xsd
UBL-CoreComponentTypes-0.81-draft-8.xsd

The XML instances created:
UBL-Invoice-0.81-draft-8-all-lists-JoineryExample.xml
UBL-Invoice-0.81-draft-8-selected-lists-JoineryExample.xml
UBL-Invoice-0.81-draft-8-JoineryExample.xml


-- 
regards
tim mcgrath
phone: +618 93352228  
postal: po box 1289   fremantle    western australia 6160

position-lcsc-listcontainers-02.zip