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---++Can I drop and re-create the DefaultQuadStorage?

Currently system metadata consist of three "levels":

   1 <b>QuadMapFormats</b> are used to describe transformations of individual SQL values (or types of SQL values), 
   1 <b>QuadMaps</b> refers to <b>QuadMapFormats</b> (via <b>QuadMapValues</b>) and describe some "minimal" independent RDB2RDF transformations,
   1 <b>QuadStorages</b> organizes <b>QuadMaps</b>. 


<b>QuadStorages</b> contains only "symlinks" to maps, if you drop a storage you don't drop all mappings inside.
If you drop the <b>DefaultQuadStorage</b> or some other built-in thing, it can be safely recovered by [[http://docs.openlinksw.com/virtuoso/fn_rdf_audit_metadata.html][DB.DBA.RDF_AUDIT_METADATA]], with first parameter set to 1. This will keep your own data intact. However we recommend to write a script that declares all your formats, Linked Data Views and storages, to be able to reproduce the configuration after any failures.

---+++Related
   
   * [[VirtTipsAndTricksGuide][Virtuoso Tips and Tricks Collection]]
   * [[http://docs.openlinksw.com/virtuoso/rdfsparql.html][SPARQL]]