Describe Oracle architecture in brief

Describe Oracle architecture in brief.

The Oracle database has:

Logical layer : The components of the logical layer map the data to these physical components.

Physical layer : The physical layer consists of the files that reside on the disk.

Tablespaces and Datafiles
The database is divided into one or more logical pieces known as tablespaces. A tablespace is used to logically group data together.

The Database Schema : A collection of logical-structure objects, known as schema objects.

These schema objects consist of structures such as:
- tables,
- clusters,
- indexes,
- views,
- stored procedures,
- database triggers, and
- sequences.

Segments, Extents, and Data Blocks
Within Oracle, the space used to store data is controlled by the use of logical structures. These structures consist of the following:

Data blocks -
A block is the smallest unit of storage in an Oracle database. (contains header information concerning the block itself as well as the data)

Extents - Extents consist of data blocks.

Segments - A segment is a set of extents used to store a particular type of data.

The Oracle Instance has:

- User processes
- Oracle background processes
- The shared memory

The Oracle Memory Structure contains:

- The System Global Area (SGA)
- The Data-Dictionary Cache
- The Program Global Area (PGA)
What is the function of SMON?
The SMON background process performs all system monitoring functions on the oracle database....
Explain different types of segment
There are four types of segments used in Oracle databases: - data segments - index segments - rollback segments - temporary segments.....
Explain SGA memory structures
SGA (System Global Area) is a dynamic memory area of an Oracle Server. In SGA,the allocation is done in granuels. The size of the SGA is dependent on SGA_MAX_SIZE parameter...
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describe oracle instance and the oracle database architecture
Please provide example
Thato Morake 03-7-2017