afs commented on code in PR #2925: URL: https://github.com/apache/jena/pull/2925#discussion_r1930805943
########## jena-arq/src/main/java/org/apache/jena/sparql/engine/iterator/QueryIterLateral.java: ########## @@ -292,17 +295,33 @@ public Op transform(OpTable opTable) { // By the assignment restriction, the binding only needs to be added to each row of the table. Table table = opTable.getTable(); // Table vars. - List<Var> vars = new ArrayList<>(table.getVars()); - binding.vars().forEachRemaining(vars::add); - TableN table2 = new TableN(vars); + List<Var> tableVars = table.getVars(); + List<Var> vars = new ArrayList<>(tableVars); + + // Track variables that appear both in the table and the binding. + List<Var> commonVars = new ArrayList<>(); + + // Index variables in a set if there are more than a few of them. + Collection<Var> tableVarsIndex = tableVars.size() > 4 ? new HashSet<>(tableVars) : tableVars; + binding.vars().forEachRemaining(v -> { + if (tableVarsIndex.contains(v)) { + commonVars.add(v); + } else { + vars.add(v); + } + }); + + List<Binding> bindings = new ArrayList<>(table.size()); BindingBuilder builder = BindingFactory.builder(); table.iterator(null).forEachRemaining(row->{ - builder.reset(); - builder.addAll(row); - builder.addAll(binding); - table2.addBinding(builder.build()); + if (Algebra.compatible(row, binding, commonVars.iterator())) { Review Comment: > For the sake of closing the issue, should I modify/simplify the logic Yes, please. > Well, the tradeoff to what extend existing implementations need to drive restrictions of new features in a standard. SHACL WG has started and SHACL Values Insertion (which is similar but different) will need SPARQL syntax level solution, which implies static rules for scoping. As will parameterized query. I hope, in spirit, these different situations have a related approach. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: pr-unsubscr...@jena.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: pr-unsubscr...@jena.apache.org For additional commands, e-mail: pr-h...@jena.apache.org