The system tenant is a built-in tenant of OceanBase Database.
It is a container for the system data of OceanBase Database. All system data and system tables are stored under its namespace.
The system tenant also performs cluster administration tasks for OceanBase Database. These include adding and removing user tenants, modifying cluster-level configuration, scheduling rotating major compactions, disaster recovery, as well as resource and load balancing. The system tenant allocates the resource needed for system operation, maintenance, and management tasks. For example, it provides resources for operations that do not involve resource splitting at the tenant level, such as leader election and rotating major compaction for log synchronization.
Key system tables
__all_core_table
__all_core_table is a metadata table at the center of all system tables. It stores the schema of other core system tables as well as the physical location metadata of __all_root_table.
__all_root_table
__all_root_table stores the physical location metadata of system tables for the system tenant and all user tenants.
__all_table_v2/__all_column
__all_table_v2/__all_column are schema tables that store the schema of all system tables.