Another way is at execution time:
QueryExecution....
.query(query string or object)
.substitution(varName, value);
which uses QueryTransformOps.
Andy
On 25/11/2024 08:40, Martynas Jusevičius wrote:
Hi Lorenz,
thanks, but wouldn't these methods append VALUES at the end of the
query? Which would not be equivalent to having it injected at the
beginning?
I don't want to build the whole query with Java -- I already have a
query string.
Martynas
On Mon, Nov 25, 2024 at 7:58 AM Lorenz Buehmann
<buehm...@informatik.uni-leipzig.de> wrote:
Hi,
you mentioned a query builder, so did you try to use the Jena query
builder already? If so,
the method addWhereValueVars on the SelectBuilder[1] or directly on the
WhereBuilder[2] would be the way to go.
Cheers,
Lorenz
[1]
https://jena.apache.org/documentation/javadoc/extras/querybuilder/org.apache.jena.querybuilder/org/apache/jena/arq/querybuilder/SelectBuilder.html#addWhereValueVars(java.util.Map)
[2]
https://jena.apache.org/documentation/javadoc/extras/querybuilder/org.apache.jena.querybuilder/org/apache/jena/arq/querybuilder/WhereBuilder.html#addWhereValueVars(java.util.Map)
On 25.11.24 01:02, David Habgood wrote:
Hi Martynas,
Do you know ahead of time which variable(s) you're going to be injecting
the VALUES clause for?
I've been using a pattern where I add VALUES ?this { UNDEF } in "template"
queries, then at runtime parse the query and replace "UNDEF" (where all of
the DataBlockValue <https://www.w3.org/TR/sparql11-query/#rDataBlockValue>s
in a binding within a InlineDataFull are "UNDEF") with a set of bindings
supplied at runtime. This has the benefit that if you do not supply a
binding for ?this, UNDEF means it is left unbound.
Thanks,
On Mon, Nov 25, 2024 at 9:40 AM Martynas Jusevičius <marty...@atomgraph.com>
wrote:
Hi,
What would be the simplest way to safely (i.e. using query builder or
algebra) to inject a VALUES block at the beginning of a query?
For example
SELECT *
{
?this ?p ?o
}
should become
SELECT *
{
VALUES ?this <http://localhost>
?this ?p ?o
}
after the injection.
Thanks,
Martynas
--
Lorenz Bühmann
Research Associate/Scientific Developer
Email buehm...@infai.org
Institute for Applied Informatics e.V. (InfAI) | Goerdelerring 9 | 04109
Leipzig | Germany