Virtual Graph Path Queries - path operator not found


I'm trying to use Path Queries with a PostgreSQL virtual graph and I'm getting the following error when I run the query. Does anyone have any insight into if this is even possible to do, or if I'm just doing something wrong?


QEQOE2: com.complexible.stardog.plan.eval.ExecutionException: Invalid path query or incorrect translation: path operator not found

Example query:

PATHS from <virtual://local-postgres> START ?x END ?y VIA ?p

Cheers, Tim.

Hi Tim,

the evaluation of path queries directly over virtual graphs is currently not supported. However, you can use path queries over cached virtual graphs.
In your example, you can cache your virtual graph on your local server instance using the following command
stardog-admin cache create cache://local-postgres --graph virtual://local-postgres.
Thereafter, you should be able to execute path queries over the cached VG with
PATHS from <cache://local-postgres> START ?x END ?y VIA ?p

For more details on caching VGs, you can checkout the Cache Management doc and the CLI doc.

Best regards


Thanks for your help Lars.
I was able to get the path queries to work using the local cache like you suggested.

To minimise the size of the cache, I created a new virtual graph mapping that only includes the relationships between classes, and used that for the cache and path queries.

Regards, Tim.

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