What is a relational database? Oracle database architecture, Oracle cluster introduction, and oracle Architecture

What is a relational database? Oracle database architecture, Oracle cluster introduction, and oracle Architecture

What is a relational database?

Databases based on Relational Models.

What is a relational model?

Use rows and columns in a two-dimensional table to maintain the data model.

Oracle database architecture

Database: database

Oracle databases are physical storage of data. Including: Data File ORA or DBF, control file, online log, parameter file ). In fact, Oracle is an operating system with only one database. It can be seen that Oracle only has one large database.

Instance:

An Oracle instance consists of a series of background processes and memory structures. A database can have n instances.

Data File (dbf ):

Data files are physical storage units of databases. To delete a data file, you can only delete the tablespace that it belongs.

Tablespace:

It is the logical ing of Oracle to related data files on the physical database.

A data file can belong to only one tablespace.

User:

The user is created under the instance. Users with the same name can be created for different instances.

Oracle Cluster

Oracle Architecture