@Test
public void testDatabaseMgr2() {

    TDBInternal.reset();
    // The unnamed location is unique each time.
    DatasetGraph dg1 = DatabaseMgr.connectDatasetGraph(Location.mem());
    DatasetGraph dg2 = DatabaseMgr.connectDatasetGraph(Location.mem());
    Txn.executeWrite(dg1, ()->{
        dg1.add(quad1);
    });
    Txn.executeRead(dg2, ()->{
        assertFalse(dg2.contains(quad1));
    });
}