Extended Result Set Model

Issue raised by: Park hee-joon Hyundai Information Technology Fri, 20 Jun 1997 20:03:21 +0900

The type-101 query (or type-1, in version 3) defines proximity and restriction. To support this, is it necessary to support the Extended Result Set (ERS) model.

No. There is no requirement to support the extended result set model.

You can support the type-101 query (or type-1 in version 3) without supporting proximity and restriction.

Suppose, however, you do support these. Consider, first, proximity. You can support proximity without supporting the "extended result set model for proximity". In other words, you might support "cat near hat" and not support "R1 near R2" where R1 and R2 are result sets representing 'cat' and 'hat' respectively.

Next, consider restriction. Strictly speaking, if you support result set restriction then you support the extended model for restriction, by definition (you have to assume that model just to be able to define the semantics). But supporting the extended model for restriction is simply an abstract concept for which there is no conformance requirement. It simply means that the server maintains some information (necessary to carry out the operation) and the manner in which it is maintained is of local concern only.