Similar to the Oracle mode, the MySQL mode also supports dynamic performance views.
Overview
The views are dynamic because they are continuously updated when a database is open and in use. The dynamic performance views provide information about the performance of a database.
Compared with regular database tables, dynamic performance views provide only data about internal disk structures and memory structures. You can query these views but you cannot update or modify them.
OceanBase Database has dynamic performance tables with names starting with V$. Views can be created on these tables, and then public synonyms with a prefix of V$ can be used.
In most cases, a V$ view corresponds to a GV$ view, which is a global V$ view. If you query a GV$ view, all qualified V$ view information will be returned.
Storage of dynamic performance views
Dynamic performance views are created based on virtual tables that are created from database memory structures.
They are not conventional tables that are stored in a database. Read consistency is not guaranteed for the dynamic performance views because data is updated in real time.
The dynamic performance views are not true tables. Therefore, data in these views varies based on the state of the cluster and service node.