Oracle logical structures
Oracle logical structures can be summarised by the following:
Schema. Tablespace. Datablock. Redo log.
Schema
- collection of objects (table, view, etc)
- owned by db user
- name is the same as db user
- mixed up (user is often used interchangeably with schema)
- access – user has access to all objects in schema
- name – user only has access to schema of the same name
Tablespace
- Logical storage units – oracle divided into one or more logical storage units
- objects – tablespace stores related database objects
- access – tablespace can be online (accessible) or offline (not accessible)
- normally online so users can access data
Datablock