How to clear all the named graphs in the Virtuoso

Virtuoso Universal Server Tips, Tricks, and HowTos
1

Hi, I’d like to clear all the named graphs in Virtuoso.
Virtuoso automatically creates some named graphs such as ‘http://www.openlinksw.com/schemas/virtrdf#’ or ‘urn:activitystreams-owl:map’.
When loading a trig file that contains lots of graphs containing relatively small number of triples, I want to obtain statistics of triples, and exclude that of these pre-existing ones.
Even clearing all the graphs explicitly cannot clear these graphs.

Thanks.

2

Hi Yayamamo,

You can’t clear the systems graphs if you want to have a functioning system. Is it that you are trying to write queries that exclude these system graphs? If so, you can use the following approaches.

1. NOT FROM <{IRI-of-graph-to exclude}>  i.e., NOT FROM CLAUSE 
2. FILTER GRAPH IRIs that include the pattern "virtrdf" via FILTER (CONTAINS(STR(?g),"virtrdf"))
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