You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@jena.apache.org by "Andy Seaborne (Jira)" <ji...@apache.org> on 2022/02/09 10:31:00 UTC
[jira] [Closed] (JENA-384) Interaction of optimization (TransformFilterEquality) and initial binding
[ https://issues.apache.org/jira/browse/JENA-384?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Andy Seaborne closed JENA-384.
------------------------------
Resolution: Done
> Interaction of optimization (TransformFilterEquality) and initial binding
> -------------------------------------------------------------------------
>
> Key: JENA-384
> URL: https://issues.apache.org/jira/browse/JENA-384
> Project: Apache Jena
> Issue Type: Bug
> Components: ARQ, Optimizer
> Affects Versions: ARQ 2.9.4, Jena 2.10.0
> Reporter: Andy Seaborne
> Priority: Major
> Attachments: ReportSubstitueOptimize.java
>
>
> substitution is normally done after optimization so that it preserves the semantics in case of complex optional situations.
> The equality filter optimization eliminates code that can't generate a solution (the variable is unbound in the subexpression)
> This can be unexpected but it's neither clearly right or clearly wrong. The semantics of initial binding need clarifying;
> either
> pure substitution semantics, with the substitution applied before optimization
> or
> VALUES semantics (join with a data table) in which case elimination of redundant pattern matching is correct.
> In the example, it's only an issue with URIs (reason?) but the general point remains.
--
This message was sent by Atlassian Jira
(v8.20.1#820001)