- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Mon, 04 Oct 2010 15:32:37 +0100
- To: SPARQL Working Group <public-rdf-dawg@w3.org>

v1.65 Main points: The definitions look right. I have a suggestion to write them differently for clarity (the details need careful checking but I thought "now" and "outline" was better than "later" and "detailed"). Andy ------------- 4.1.2: The use of time isn't necessary - see below where t isn't used. 4.1.3 UpdateOperation Need to define UpdateRequest as a sequence of UpdateOperations. An UpdateRequest is atomic. Applying an UpdateRequest is defined as applying each UpdateOperation in sequence order. 4.2.1 InsertDataOperation Need to say something about how the {triples} and {(<i>, triples_i)} come about. It's {(<i>, {triples_i)}} -- an extra {} to show it's a set of triples a set of pairs of uri and a set of triples (= a graph). <i> gets overused. It would be clearer to distinguish <i> in the starting GS and the <j>, say, coming from the operation. UNION: Set union doesn't quite do the right there here. It does not merge the two structures which is what we want. I think the best way is to define two auxillary operations GS-UNION and GS-DIFF that do the work (they get used several times in the definitions): Write DS' = {triples}, {(<j>, {triples_j})}) from parsing then Write I for the set of <i>, J for the set of <j> OpInsertData(GSS(GS), DS') = GS-UNION(GSS,DS') where GS-UNION(GSS, DS) = GS-UNION((DG1, {(<i>, G_i)}), (DG2, {(<j>, G_j)}) = ( DG1 union DG2, {{triples_k}) | k in I union J }) where {triples_k} = {triples_i} union { triples_j} if i = k, j = k and k in I and k in J {triples_k} = {triples_i} if i = k, k in I and k not in J {triples_k} = {triples_j} if j = k, k in J and k not in I GS-DIFF is the same except {triples_k} = {triples_i} set-difference { triples_j} if i = k, j = k and k in I and k in J {triples_k} = {triples_i} if i = k, k in I and k not in J No { triples_k} if k in J and not I. Without the auxiliary functions, I found myself having to repeat this block of definitions which lead to rather large definitions. 4.2.2 DeleteDataOperation Same except GS-DIFF and mention what happens about any (<i> {}) that arise. 4.2.3 DeleteInsertOperation Could this be broken up a bit? P = pattern (WHERE clause) B = bindings from solve P D = delete template I = insert template X = ({triples}, {(<i> {triples_i})} formed by D(B) Y = ({triples}, {(<i> {triples_i})} formed by I(B) OpDeleteInsert(GSS(GS), D, I, P) = GS-UNION(GS-DIFF(GSS, X), Y) 4.2.4, 4.2.5 similarly. 4.2.6 DeleteWhereOperation Set D=P, noting the restricted P. 4.2.7 LoadOperation Define X = triples from remote and use GS-UNION 4.3.2 s/{()}/{}/ --it's an empty set, no tuples. () woudl be the zero-length tuple.

Received on Monday, 4 October 2010 14:33:20 UTC