Ivan, I've finally made a full log of the test we use. It is available at http://lvk.cs.msu.su/~lasaine/sparql.sql.bz2
I've also compared the contents of two system graphs (http://www.openlinksw.com/schemas/virtrdf#, http://localhost:8890/DAV) of an empty database and the database after the test. They are identical so the system information is untouched. However, I cannot delete 29 triples (by the way, the type of object is always int, boolean or nonNegativeInteger). I decided to make an archive of the database. You can obtain it from here (~2MB): http://lvk.cs.msu.su/~lasaine/db.tar.bz2 The failing queries can be obtained from http://lvk.cs.msu.su/~lasaine/del.sql. Please help me fix this issue! Thanks! -- Alexander