ORDER BY not working with activated optimizer

[LorenzBuehmann]

Part of the endpoint? (leave empty if you don't know)

• Backend (qendpoint-backend)
• Store (qendpoint-backend)
• Core (qendpoint-core)
• Frontend (qendpoint-frontend)
• Other

Description of the issue

Any query with ORDER BY doesn't work, e.g.

SELECT ?s WHERE {
  VALUES ?s {1 2 3 4 5}
} ORDER BY DESC(?s)

returns

1
2
3
4
5

Deactivating the OrderLimitOptimizer in EndpointStoreQueryPreparer class makes sorting work, so I assume it's a combination of how RDF4J does replace child and parent nodes (probably line 68 in OrderLimitOptimizer class) in the corresponding optimizer and how you consume the optimized TupleExpr in the ExtendedEvaluationStrategy?

You can also see from the query plan that something is wrong and the sorting part has been dropped somehow

ProjectionElem "s"

ProjectionElemList

BindingSetAssignment ([[s="1"^^<http://www.w3.org/2001/XMLSchema#integer>], [s="2"^^<http://www.w3.org/2001/XMLSchema#integer>], [s="3"^^<http://www.w3.org/2001/XMLSchema#integer>], [s="4"^^<http://www.w3.org/2001/XMLSchema#integer>], [s="5"^^<http://www.w3.org/2001/XMLSchema#integer>]])

Projection

Excepted behavior

correct result:

5
4
3
2
1

Obtained behavior

wrong result:

1
2
3
4
5

How to reproduce

1. Run Application class from source code or Docker image
2. Execute

SELECT ?s WHERE {
  VALUES ?s {1 2 3 4 5}
} ORDER BY DESC(?s)

Endpoint version

1.13.8

Do I want to contribute to fix it?

No

Something else?

No response