Re: Fuseki: how can I inject standard prefixes to every query?

[Andy Seaborne]

On the query page, there is a "prefixes" area above the endpoint setting 
for inserting prefixes.

For queries from a program, prepend some text to each query sent in 
whatever programming language you are using. If a prefix is redefined 
twice in syntax, the second overwrites the definition:

PREFIX ex: <http:/example.org/>
PREFIX ex: <http:/example.org/ex#>

"ex:" is "http:/example.org/ex#"

Contributions for improvements welcome!

    Andy

On 03/09/2021 08:11, Michael Wechner wrote:
Thanks for the clarifying example!

Similar to wikidata query https://query.wikidata.org/ where you can 
enter a query without defining prefixes, for example

SELECT ?item ?itemLabel ?dateOfBirth ?workLabel WHERE {
   ?item wdt:P31 wd:Q5.
   ?item ?label "Alfred Hitchcock"@en .
   OPTIONAL{?item wdt:P800 ?work.}
   OPTIONAL{?item wdt:P569 ?dateOfBirth .}
   SERVICE wikibase:label { bd:serviceParam wikibase:language "en". }
}

I agreee, for standard prefixes like for example "rdfs" this would be 
very convenient, but I don't know whether this feature does not exist by 
design or because it was not a high priority yet or whether it exists, 
but requires some configuration.

Does anyone else know?

Thanks

Michael

Am 03.09.21 um 08:51 schrieb Laura Morales:
What I mean is really simple. Basically I'd like to send queries like 
this to Fuseki:

     SELECT ?l
     WHERE { ?s rdfs:label ?l }

this is not a valid query because it does not define the rdfs prefix. 
But I'd like to prepend some standard prefixes to every incoming 
request before they are executed. So the request above is transformed 
into this before being executed:

     PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
     SELECT ?l
     WHERE { ?s rdfs:label ?l }

Now I've made an example with rdfs and I hope it's simple enough and 
that it makes sense. In practice, I'd like to have a list of prefixes, 
even custom ones. My endgoal is that I can send queries without having 
to define any PREFIX because they are automatically attached by the 
server, at every request. If I need any particular prefix, or if I 
need to override one of the default prefixes, than those will be 
specified in the specific query.

Hope it makes sense, thank you.




Sent: Friday, September 03, 2021 at 8:35 AM
From: "Michael Wechner" <michael.wech...@wyona.com>
To: users@jena.apache.org
Subject: Re: Fuseki: how can I inject standard prefixes to every query?

can you give an example?

Thanks

Michael