Oracle-compatible views in MySQL tenants

This topic describes some Oracle-compatible views in a MySQL tenant of OceanBase Database.

Storage location

Oracle-compatible views in MySQL tenants and the sys tenant are stored in the OceanBase database and can be accessed only from MySQL tenants and the sys tenant.

Characteristics

Oracle-compatible views in MySQL tenants have the following similarities with and differences from standard Oracle views.

• Similarities:

  • The view names are prefixed with DBA_.
  • The column names and implementation are consistent with standard Oracle views prefixed with DBA_.

• Differences:

  The columns with the same name have different meanings. In standard Oracle views, the OWNER column represents USER, while the CON_ID column represents container_id. However, in a MySQL tenant, they correspond to Database and tenant_id respectively.

View types

Oracle-compatible views in MySQL tenants include data dictionary views and dynamic performance views.

• Data dictionary views are prefixed with oceanbase.DBA_ and display information about some database objects in the current tenant.
• Dynamic performance views are prefixed with oceanbase.V$ or oceanbase.GV$. Almost every view prefixed with oceanbase.V$ has a corresponding view prefixed with oceanbase.GV$. In an OceanBase cluster, all views prefixed with oceanbase.GV$ that meet the conditions are returned when you query oceanbase.V$* views.

References

• OceanBase-specific views
• MySQL-compatible views