Virtuoso Tips and Tricks
We have a number of tips and tricks articles, covering various areas of Virtuoso functionality.
Database Administration
- How can I specify an OS user name to which the Virtuoso server will switch after opening the listen ports?
- How can I find out which tables are deadlocking?
- How can I configure parameters to avoid out of memory errors?
- How can I control normalization of UNICODE3 accented chars in the free-text index?
- What should I do if the Virtuoso Server is not responding to HTTP requests?
- How can I perform a checkpoint against a clustered Virtuoso Server?
- How can I handle checkpoint condition?
- How can I backup and restore individual table(s) and individual index(s) on a a new fresh db?
- How Do I Generate Transient and/or Persistent Linked Data Views atop ODBC or JDBC accessible Relational Data Sources?
- How Can I perform SQL login with X 509 WebID watermarked certificate?
- How do I recover from "Invalid log entry in replay" when transaction log is being replayed during server start?
- How can I move a Virtuoso database from one hardware and/or software platform to another?
- What should I do if the Virtuoso Server is not responding to HTTP requests?
- How can I set up Virtuoso Lite Mode?
- How can I use the LD Meter Utility?
- How to proxy Virtuoso HTTP server through Apache HTTP server front end?
- How to configure Virtuoso Cluster slave nodes HTTP listeners?
- How to configure Virtuoso Elastic Cluster?
- How to Monitor Virtuoso Memory Consumption?
RDF data management
- How can I obtain a list of all graphs?
- How to manage Graph Security Level for SQL Clients?
- How can I test whether two graphs are equal?
- How can I add triples to a graph?
- How can I update triples in a graph?
- How can I delete triples from a graph?
- How can I delete triples from a "Large" graph?
- How Can I Delete Triples containing blank nodes?
- How can I copy triples from one graph to another?
- How can I move triples from one graph to another?
- How can I drop a graph?
- What is the difference between "DELETE FROM GRAPH" and "CLEAR GRAPH"?
- How can I drop a graph for which is not clear was it created explicitly or not?
- How can I perform RDF dumps from Virtuoso Quad store hosted data?
- How can I perform Dump of RDF Graphs into NQuad dumps?
- How can I delete graphs using stored procedure?
- How Can I Delete Triple Patterns that are not scoped to a named graph?
- What are the differences between create, drop, clear and delete Graph?
- What are "Generate RDB2RDF triggers" and "Enable Data Syncs with Physical Quad Store" Linked Data Views options?
- How Can I Diagnose problems associated with Linked Data views generation?
- How can I display only some information from RDF graph?
- Can I drop and re-create the DefaultQuadStorage?
- How can I define a graph with virt:rdf_sponger option set to "on"?
- How can I configure Sponger to use Asynchronous Query (AQ) threads?
- How Do I Perform Bulk Loading of RDF Source Files into one or more Graph IRIs?
- How to exploit RDF Schema and OWL Inference Rules with minimal effort?
- How the power of OWL based inference enables us exploit the power of Linked Vocabularies?
- How can I insert binary data to Virtuoso RDF storage in plain queries and with parameter binding via ADO.NET calls?
- How can I replicate all graphs?
- How can I insert RDF data from Visual Studio to Virtuoso?
- How to rename a RDF Graph in the Virtuoso Quad Store?
- How can I configure Virtuoso for maximum performance with available memory?
- How can I use the LOAD command to import RDF data?
- How can I incorporate Content Negotiation into RDF bulk loaders?
- What free-text options can I use with bif:contains?
- How can use bif:contains after SPARUL INSERT?
- How Do I Gecode Data?
- How I Delete a Specific Triple Across Graphs?
- How Do I configure Sponger Cartridges?
- How Do I protect Sponger Endpoint via ACL-s?
- How do I administer Virtuoso Sponger Instance?
- How to control user agent usage of Sponger Resources?
- How Do I use transitive SPARQL query options and Exploit Inference Rules?
- How Do I use Transitivity via Inference Rules and Transitivity for lists?
- How Can I Import Linked Data using the Briefcase "Create" feature?
- What is the ShortenLongURIs Virtuoso configuration parameter?
- How can I fix RDF Quad Store Index corruption in commercial Release 6.2 and earlier builds
- How Can I perform Simple Linked Data Deployment using Virtuoso's HTTP Re-write Rules?
- How Can I Use Virtuoso's Anytime Query Feature?
- How Can I Split 3.4billion triple UniProt datasets file?
- How Can I insert triples via Digest Authentication into the Quad Store?
- How to Update Large SPARQL Data avoiding database checkpoint abortion?
- How can I Load Data into Virtuoso in Transaction Mode (ie auto commit OFF)?
- How to convert from Row Store to Column Store Table?
- How can I determine the time taken to load datasets with RDF Bulk Loader
- How to create a RDF Graph Replication slave Subscriber node from a master Publisher node
SPARQL and SPARUL (SPARQL/Update)
- What Virtuoso Sponger SPARQL pragmas are supported?
- Are Custom SPARQL Extension Functions supported and how can I use them?
- How do I configure Virtuoso to support "wide characters" (e.g., Unicode, UTF-8) for SPARQL querying?
- How can I optimize SPARQL query performance using bifs (built-in functions)?
- How can I generate a unique ID via SPARQL?
- What reification alternatives can I use for Linked Data publishing?
- Virtuoso Linked Data Deployment In 3 Simple Steps
- Is there a difference between a "merge" vs "one by one" execution of queries across named graphs?
- How can I use iSQL to execute SPARQL queries containing the dollar-sign ("$") character?
- How can I set the quad storage to be included in results of queries made to the SPARQL endpoint?
- How can I convert between data types using SPARQL in Virtuoso?
- Is it possible to have the SPARQL endpoint on a different port than the Conductor?
- How can I manage Date Range SPARQL queries?
- How to optimize bif:dateadd in SPARQL query using selective index-friendly filter?
- How do I use SPARUL to change a selection of property values from URI References to Literals?
- How can I use CONSTRUCT with Prepared Statements?
- How can I use Expressions inside CONSTRUCT, INSERT and DELETE?
- How can I use INSERT via CONSTRUCT Statements?
- How can perform SPARUL Updates without transactional log size getting exceed?
- How can I get certificate attributes using SPARQL?
- How does default DESCRIBE mode work?
- How can I dump arbitrary query result as N-Triples?
- How do I bind a named graph parameter in a prepared statement?
- How can I perform Case Insensitive Search across multiple literal values with Virtuoso?
- What is best method to get a random sample of all triples for a subset of all the resources of a SPARQL endpoint?
- How can I use SPARQL to make Meshups?
- How can I get an exact mapping for a date?
- How can I use SPARUL to add missing triples to a Named Graph
- How can I use the SPARQL IF operator for SPARQL-BI endpoint?
- How can I perform search for predicate values?
- How to clear graphs which are related to empty graphs?
- How can I enable Dynamic Extended Types (DETs) on a Virtuoso SPARQL Endpoint?
- How can I use sub-queries to enable literal values based joins?
- How can I execute query with labels preference order?
- How can I get object datatype?
- How to achieve best performance executing a query against SPARQL Endpoint?
- What methods can I use to protect SPARQL Endpoint?
- How Do I assign SPARQL role to SQL user?
- When should I use the function SAMPLE and when GROUP_CONCAT or GROUP_DIGEST?
- How can I include aggregate function values as objects in SPARQL CONSTRUCT queries?
- How Do I Clean Up Errant Data using SPARQL Update Language?
- How to Use SPARQL to add missing isDefinedBy relations to an Ontology?
- How to Import Ontology?
- How Can I Use MODIFY to update triples?
- What are the supported authentication methods associated with a purpose specific default SPARQL endpoint?
- How Can I execute INSERT/DELETE (SPARUL) statements against a WebID protected SPARQL endpoint?
- How to expose Linked Data View URIs associated with "References" on a given Table?
- How Can I perform SPARQL Date Arithmetic calculations?
- How Can I send SOAP requests to Virtuoso SPARQL Endpoint?
- How Can I manage Custom Controlling Virtuoso Labels for URI functionality?
- How Can I Prevent Limits of Sorted LIMIT/OFFSET query?
- How can I get a full "explain" and "profile" plans for a simple SPARQL query?
- How Can I Use the core feature of SPARQL logic of pattern matching?
- How To Let the SPARQL Endpoint Save Results In WebDAV?
- Where can I find examples for SPARQL 1.1 Features supported in Virtuoso?
- How Can I use Built-In Functions?
- How Can I use BIND?
- How Can I use VALUES?
- How Can I use Sub-queries?
- How Can I use NOT EXISTS and MINUS?
- How Can I use Assignments?
- How Can I use Property Paths?
- How Can I use SPARQL Named Graphs with SPARQL 1.1 Property Paths and Reasoning?
- SPARQL 1.1 Update -- Graph Update:
- How Can I use INSERT DATA?
- How Can I use DELETE DATA?
- How Can I use INSERT/DELETE DATA?
- How Can I use LOAD?
- How Can I use CLEAR?
- How Can I use SPARQL 1.1 INSERT patterns and CONSTRUCT to Enhance Existing Data?
- SPARQL 1.1 Update -- Graph Management:
- How Can I use CREATE?
- How Can I use DROP?
- How Can I use COPY?
- How Can I use MOVE?
- SPARQL 1.1 Graph Store HTTP Protocol:
- How Can I use HTTP POST, HTTP PUT, HTTP GET and HTTP DELETE?
- What SPARQL/SPARUL/SPARQL-BI Operations can I perform within Single/Multiple Statements?
- How Can I use the Virtuoso SPARQL LOAD Service?
- Where can I find examples for SPARQL Arithmetic Functions supported in Virtuoso?
- Where can I find examples for Linked Data SPARQL Reference Using the Gene Ontology?
- How Can I Escape double quotes in entity name?
- How can I use {is property of} syntax to express inverse relations in Turtle?
- How can I use the Virtuoso specific query optimizer hint ASSUME?
- How to discover the capabilities of a SPARQL endpoint en route to enhancing SPARQL-FED usage from Virtuoso instances using LOAD SERVICE ... DATA?
- How to add SPARQL Endpoint Capabilities Interrogation to Virtuoso SPARQL-FED functionality?
- How to discover parameters used by SPARQL services that don't support SPARQL-FED?
- How to handle SPARQL-FED queries for SPARQL endpoints with no OPTION() clause supported?
- How to split a urlencoded ";-" separated list of urls in a SPARQL query
- How Can I analyze Linked Open Data with R?
- How to Interrogating attributes of a Virtuoso Server instance via SPARQL
Pivot Viewer and CXML
- What are Pivot Collections and does Virtuoso support SPARQL CXML?
- What are the main components of the PivotViewer UI and Collection XML?
- Does the Virtuoso SPARQL protocol endpoint /sparql supports extensions to the SPARQL standard specifically for CXML?
- What RDF to CXML Mapping does Virtuoso support?
- What are the default settings for the CXML generation?
- Where can I find more details about the Auto-Detection of Facet Type?
- Configure the Query Timeout setting for the Virtuoso Facet Browser?
- What are the SparqlCxml Reserved Query Variables?
- How can I use the virtcxml graph?
- How can I use Labels in Place of URIs?
- What are the Link Typing specifics?
- Where can I find examples for SPARQL CXML Queries?
- What are the SparqlCxml Deep Zoom Collections for and how can I use them?
- How can I use the PivotViewer?
- How can I import CXML?
- What is the Facet Pivot Bridge?
- What are DETs and how can I used them for persisting SPARQL Query Results to DAV?
- What CXML params are supported for the SPARQL URL pattern?
- How can I change the Facet "Demo Queries" link?
- How can I change the Facet "/describe" page?
Other areas
- Who Am I
- How to attach a CSV document to Virtuoso Database Server Instance?
- How to read Virtuoso Transaction logs?
- How can I perform Query Optimization Diagnostics?
- Manage Linked (Open) Data
- How Can I Use OpenID+WebID?
- How can I use the WebID Identity Provider Proxy Service?
- How can I use the WebID Identity Verification Service?
- How can I use LDAP based WebIDs?
- How can I use the Virtuoso Mail Verification Service?
- How can I enable the Virtuoso Entity Framework 3.5 ADO.Net Provider in Visual Studio 2010?
- How can I write custom crawler using PL?
- How can I make Multi Thread Virtuoso connection using JDBC?
- How can I output the result of a SQL SELECT query from isql to a file in Virtuoso?
- How can I output the results of a SPARQL query run against the /sparql endpoint to a file in Virtuoso?
- How can I setup Server-side Cross-Origin Resource Sharing (CORS) using Virtuoso?
- How can I perform Cross-Origin Resource Sharing (CORS) to enable a Virtuoso SPARQL Endpoint?
- How Can I execute load of sql dump from jdbc?
- How can I make Recording in Virtuoso?
- How can I make internal HTTP redirects?
- Virtuoso Data Center Tips and Tricks
- Understanding Relationship semantics and reasoning
- How to Determine Data Usage?
- How to configure the User Agent Identity used by a Virtuoso Sponger instance?
- How to Manage SSL Protocols and Ciphers used with Virtuoso?
- How to extend URIQA DefaultHost value for properly using Facet Browser as search engine?
- Understanding Virtuoso Timezoneless Datetimes