As any experienced Teradata DBA will tell you there are some tables in the Teradata dictionary (DBC) that need housekeeping. But some customer sites that I have worked with ignore table DBC.AccessRights.
If you have ever analyzed this table on a Teradata system, you will almost certainly spot two things very quickly.
Further analysis of the content of this table will usually show that a lot of the rows are ‘redundant.' By that I mean the situation where a user has a particular Access Right at the object level (say SELECT on a table), and they also have the same Access Right at the database level. Therefore the object level Access Right serves no purpose because even without it the user can SELECT from the table.
Housekeeping this table can have significant effects: one customer where a process was implemented reduced the row count by @40% which then also helped with parsing CPU consumption.
To effectively housekeep this table some best practices have to be put into place: