Projects/Nepomuk/VirtuosoInternal: Difference between revisions

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== status ==
== status ==
== sparql_to_sql_text ==
== 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.
<syntaxhighlight lang="sql">
varchar sparql_to_sql_text
( in squery varchar );
</syntaxhighlight>
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

Revision as of 16:09, 8 August 2012

Connecting directly to virtuoso

via isql

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

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