Re: [Virtuoso-users] SPARQL OPTIONAL performance

2014-03-24 Thread Jerven Tjalling Bolleman
Hi Nicola, A slightly faster form is to make one OPTIONAL with an UNION instead of two OPTIONALs. e.g. CONSTRUCT { ?p ?o. ?sub ?p_sub ?o_sub. ?type ?p_type ?o_type. } where { ?p ?o OPTIONAL { {

Re: [Virtuoso-users] SPARQL OPTIONAL performance

2014-03-21 Thread Kingsley Idehen
On 3/21/14 11:54 AM, ghirardi nicola wrote: I have this kind of queries that do not perform as expected (transaction timeout usually). Here an example on dbpedia: CONSTRUCT { ?p ?o. ?sub ?p_sub ?o_sub. ?type ?p_type ?o_type. } where {

[Virtuoso-users] SPARQL OPTIONAL performance

2014-03-21 Thread ghirardi nicola
I have this kind of queries that do not perform as expected (transaction timeout usually). Here an example on dbpedia: CONSTRUCT { ?p ?o. ?sub ?p_sub ?o_sub. ?type ?p_type ?o_type. } where { ?p ?o OPTIONAL