>> 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 ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org