[to]oracle relationships between databases, tablespaces, instances, services

1. Each database--can contain multiple instance--each instance can contain multiple tablespace and user (granting the user permission to read and write tablespace)--Each tablespace can contain multiple DBF files--common table or view, etc. are stored in tablespace.

2. For Oracle to use

Install database First, then create instance, create Tablespace with SYSDBA, add user-specified tablespace, give user authorization, login with user, create TABLE, etc.

3. After the Oracle instance is started, there will be multiple processes that provide different services.

the relationship between the database and the instance :

A database can contain one or more instances.
The definition of the instance: consists of the operating system background process and the allocated memory area. The simple point is that Oracle allocates memory areas in the Nomount state, and an instance is almost fast formed.
An instance is a dynamic concept that consists of a series of processes and memory regions.
The database is a static concept, mainly refers to the formation of a database of a series of files.
such as data files, redo log files, control files, and so on.
In general, the instance and database are one to the other, but in a multi-instance database environment, a database can correspond to multiple instances.

[to]oracle relationships between databases, tablespaces, instances, services