>> 2. deal with circles in GRANT graph.
>
> Can you give an examle for how this is any different for column-level
> GRANTs?
When judging if there are any circles in the grant graph, we can represent
table priviledges as column priviledges, thus make things easier. I have not
think hard enought to figure out a better algorithm.
Another problem is, should we allow any circles to be formed when executing
GRANTs? Say: <grantor1, grantee1, object1, priviledge1, with grant option>, <grantee1, grantee2, object1,
priviledge1,with grant option>, <grantee2, grantor1, object1, priviledge1, with grant option>,
should the third GRANT be executed successfuly?
I remember that MSSQL 2000 and ORACLE 9i are different.
William ZHANG