schemas
The function check_one_table_access() called to check access to tables in 
SELECT/INSERT/UPDATE was doing additional checks/modifications that don't hold
in the context of setup_tables_and_check_access().
That's why the check_one_table() was split into two : the functionality needed by
setup_tables_and_check_access() into check_single_table_access() and the rest of 
the functionality stays in check_one_table_access() that is made to call the new
check_single_table_access() function.