单主机架构
System Database
- The system database does not have the same functionality as a tenant database.
- The system database is not a database with full SQL support.
- The system database cannot be distributed across multiple hosts, in other words, scale-out is not possible.
- If you need a full-featured SAP HANA database, you always have to create at least one tenant database.
- The system database does not support Application Function Libraries (AFL) and SAP liveCache applications.
- Cross-database access between the system database and a tenant database is not possible. The system database can show monitoring data from tenant databases (views in the schema SYS_DATABASES) but can never show actual content from tenant databases.
- The system database cannot be copied or moved to another host.
- SAP HANA options can only run in tenant databases.
- Tenant-specific configurations cannot be set in the system database. Only global settings are allowed.
- Features can only be restricted or disabled at high level for tenant databases.
Tenant Databases:(Database-related topology information is stored in the relevant tenant database catalog.)
- Set of database users
- Database catalog
- Repository
- Persistence
- Backups
- Traces and logs
https://help.sap.com/viewer/6b94445c94ae495c83a19646e7c3fd56/2.0.04/en-US/f9aba40d6c4c4ae48cce461db4d42d88.html