GRANT Table or Columns

[Douglas Rafael]

Is there any way to grant or revoke access  at level of field ?

i.e.:   user1,user2,user3 can access database dt_test.
        Each user, have 3 tables. (9 tables on total)

        How do I do to grant/revoke access only to 3 tables and dont to 9
tables ?
        How do I do to revoke access only some fields of the tables ?

        I ask because with combo host+user+db, I only get grant/revoke
access
        to database/user/host ! Is it correct ?

Thanks

Douglas