Stored query vars not bound with BIND

Support
1

I am trying to create a unique label for instances of a certain type by binding one of the strings returned by a stored query. The query looks something like this:

SELECT ?my_label ?record_label ?my_label_extended ?my_record_extended ?my_label_record
WHERE {
    SERVICE <query://my-query> { 
            [] sqs:vars ?my_label, ?my_table
            }
    GRAPH <virtual://my-database> {
          ?record a ?my_table ;
                rdfs:label ?record_label .
          BIND (CONCAT(STR(?my_label), "-Record-") AS ?my_label_extended)
          BIND (CONCAT("Record-", STR(?record_label)) AS ?my_record_extended)
          BIND (CONCAT(STR(?my_label), "-Record-", STR(?record_label)) AS ?my_label_record)
    }
}

The results will bind the values for ?my_label, ?record_label, and ?my_record_extended but not ?my_label_extended or my_label_record. So it looks like there is some issue using BIND with sqs:vars.

Placing the CONCAT directly in the SELECT as a variable works to overcome this, but I am trying to return this label in a CONSTRUCT query so I believe using BIND is the correct/only option.

Any thoughts on what might be going on here?

2

Hi Nolan,

Can you show the query plan? It kind of looks like that your BIND statements should be outside of the GRAPH <virtual://my-database> {..} block, otherwise the SQS variables aren't bound when those BINDs are evaluated.

Cheers,
Pavel

3

Hi Pavel,

Thanks! I took a look at the query plan and the problem variables were not present. I tried your suggestion and moved the BIND to the outer scope and that solved the issue =)

Cheers,

Nolan

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