{"id":26,"date":"2015-01-19T18:07:23","date_gmt":"2015-01-19T17:07:23","guid":{"rendered":"http:\/\/67bricks.com\/blog\/2015\/01\/19\/virtuoso-jena-provider-problem\/"},"modified":"2021-12-16T10:56:17","modified_gmt":"2021-12-16T10:56:17","slug":"virtuoso-jena-provider-problem","status":"publish","type":"post","link":"https:\/\/blog.67bricks.com\/?p=26","title":{"rendered":"Virtuoso Jena Provider Problem"},"content":{"rendered":"<p>In a project that we&#8217;ve just started, we are using OpenLink Virtuoso as a triple store. I encountered a frustrating bug when accessing it via the <a href=\"http:\/\/virtuoso.openlinksw.com\/dataspace\/doc\/dav\/wiki\/Main\/VOSDownload#Jena%20Provider\">Jena Provider<\/a> where submitting a SPARQL query with a top-level <code>LIMIT<\/code> clause would return one less result than expected. In my case, the first query I tried was an existential query with <code>LIMIT 1<\/code>, so it caused much head scratching as to why I was getting no results.<\/p>\n<p>Luckily OpenLink are responsive to issues raised on GitHub, so once I raised <a href=\"https:\/\/github.com\/openlink\/virtuoso-opensource\/issues\/296\">this issue<\/a> and created&nbsp;<a href=\"https:\/\/github.com\/67Bricks\/virtuoso-jena-test\">an example project<\/a>, it was quickly found to be solved by using the latest version of their JDBC4 jar. Problem solved.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In a project that we&#8217;ve just started, we are using OpenLink Virtuoso as a triple store. I encountered a frustrating bug when accessing it via the Jena Provider where submitting a SPARQL query with a top-level LIMIT clause would return one less result than expected. In my case, the first query I tried was an &hellip; <a href=\"https:\/\/blog.67bricks.com\/?p=26\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Virtuoso Jena Provider Problem&#8221;<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-26","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/posts\/26","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=26"}],"version-history":[{"count":1,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/posts\/26\/revisions"}],"predecessor-version":[{"id":301,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=\/wp\/v2\/posts\/26\/revisions\/301"}],"wp:attachment":[{"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=26"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=26"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.67bricks.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=26"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}