Projects/Nepomuk/VirtuosoInternal: Difference between revisions

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= Common Commands =
= Common Commands =
Apart from directly running SQL and SPARQL queries, virtuoso also provides some additional commands, which are listed over here.
== status ==
== status ==
== sparql_to_sql_text ==
== sparql_to_sql_text ==

Revision as of 17:13, 8 August 2012

Connecting directly to virtuoso

Virtuoso ships with an executable called isql-vt. Just running that executable should connect you to virtuoso.

If you distribution does not provide the corresponding executable or if it doesn't work for you. Try this script -

#!/bin/bash
filename=`ps aux | grep virtuoso-t | grep -v grep | sed -e 's/.*\/tmp\///;s/ini.*/ini/'`
port=$(grep ServerPort /tmp/$filename | sed -e 's/.*=//')
exec isql-vt -S $port

List of tables

is a relational database and what not

All the tables in Virtuoso start with the DB.DBA. prefix.

  • RDF_QUAD -- The main table which contains all the statements. It contains four rows "S", "P", "O" and "G" for the subject, predicate, object and graph.

Default Indexes

Common Commands

Apart from directly running SQL and SPARQL queries, virtuoso also provides some additional commands, which are listed over here.

status

sparql_to_sql_text

The sparql_to_sql_text() function can be used to convert a SPARQL query directly to the SQL it would be executed as.

varchar sparql_to_sql_text
( in squery varchar );


It's very useful in debugging why many sparql queries are taking so long.

http://docs.openlinksw.com/virtuoso/fn_sparql_to_sql_text.html