SAP HANA supports multiple isolated databases in a single SAP HANA system. These are referred to as tenant databases.
An SAP HANA system is capable of containing more than one tenant database.
A system always has exactly one system database, used for central system administration, and any number of tenant databases (including zero). An SAP HANA system is identified by a single system ID (SID). Databases are identified by a SID and a database name. From the administration perspective, there is a distinction between tasks performed at system level and those performed at database level. Database clients, such as the SAP HANA studio, connect to specific databases.
All the databases share the same installation of database system software, the same computing resources, and the same system administration. However, each database is self-contained and fully isolated with its own:
Set of database users
Database catalog
Repository
Persistence
Backups
Traces and logs
Only the system database runs the name server. The name server contains landscape information about the system as a whole, including which tenant databases exist. It also provides indexserver functionality for the system database.
Tenant databases require only an own index server. Servers that do not persist data, such as the compile server and the preprocessor server, run on the system database and serve all databases.
The following figure shows a sample system with three databases (system database and two tenant databases) on a single host.
