I set up a brand new user in Oracle called Smith and give him "Connect" role only, default table space and quota to unlimited access to his table spaces.
There's no other system privileges or object privileges granted.
However, for some reason, if i log in as this user, i can delete rows from another schema, for example Doe, if i do this:
delete from Doe.testtable where testcolumn=1234;
How can I stop this?