问题
Im working on Oracle Database 11g:
If user A gives the following privileges to user B on a table 'emp' using:
Grant select on emp to userB WITH GRANT OPTION;
User B gives the same to user C using:
Grant select on emp to userC WITH GRANT OPTION;
Once this happens, user A uses this:
Revoke select on emp from userB;
What is the outcome of the following? Im a bit confused on this.
回答1:
As long as user B has been granted to "select on emp ... WITH GRANT OPTION" he may forward this privilege to somebody else. If the privilege is revoked he cannot do this anymore. (neither select table emp nor grant select to sombody else)
Take a simpler example: GRANT CREATE TABLE to USER_A. As long as USER_A has this privilege he can create a new tables. If the privilege is revoked he cannot do this anymore. In this case the table he created before will not be dropped, of course. The table stays as it is.
The same applies for SELECT privileges.
回答2:
According to this blog, the select privilege will automatically be revoked from userB and userC. This will cascade to any other user who were granted this previlige from userB or any of its grantees.
来源：https://stackoverflow.com/questions/25231809/revoke-option-used-on-first-user-after-using-with-grant-option