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* In section 5.1 the selectivity estimati …
* In section 5.1 the selectivity estimation for bound object is done separately for bound and unbound properties.
** This is contrary to the assumption that selectivities of s, p , o are independent.
** When p is unbound the selectivity value can be >1, not just theoretically.
* Selectivity Estimation is so naive, rudimentary. They should have at-least tried to estimate sel using sel(s)*sel(s/p)*sel(o/s,p) or sel(s)*sel(s/p)*sel(o/p) and suggested the required statistics and how these statistical informations be created. Moreover, this involves pre-processing (nothing done at query time). Only negative impact is the increase in size of summary data, but that's affordable.
e of summary data, but that's affordable.
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