The TDMaps database, and its tables and views, stores metadata that is used by the system when moving tables to new maps. TDMaps also contains SQL procedures that perform tasks related to system expansion.
For information about MAPS architecture (MAPS), see Teradata Vantage™ - Database Administration, B035-1093 and Teradata Vantage™ - SQL Operators and User-Defined Functions, B035-1210.