DBMS (database management system) is a set of software and hardware tools with which you can design, configure and administer databases (DBMS). DBMS guarantees the safety, integrity, security of data storage and allows you to grant access to database administration.
SORM solutions
Key features
The DBMS provides:
- interaction with information stored on external storage devices;
- working with “hot” data that is located in RAM or on SSD;
- logging of each stage when working with the database;
- support for most database formats.
What is included in the DBMS
The DBMS consists of:
- Cores. Supports reporting, is responsible for managing data in RAM and on external drives.
- The processor of the DB language. Handles incoming user or administrator commands. Optimizes queries for creating and modifying data.
- Execution time support subsystems. It allows you to interpret software solutions with current databases, as well as create user interfaces (APIs) with DBMS.
- Auxiliary software. System utilities that provide additional database management and administration functions.
Types of DBMS
DBMS are classified into different types depending on the models of the data used, the ways to provide access to the database, as well as the level of distribution.
Depending on the DBMS data model, there are:
- network;
- hierarchical;
- relational;
- object-relational;
- object-oriented.
According to the method of providing access to the database, DBMS are divided into:
- embedded;
- “client-server”;
- “file server”.
According to the level of DBMS distribution, there are:
- geo-distributed (the components of a single DBMS are distributed across different equipment, which may be geographically located in different places);
- local (the software is installed in the same data center).
DBMS interaction schemes with external memory
Database management systems can work with information on external media by deferred and direct recording.
When recording is delayed, changes to the database are recorded in the clipboard on external drives until:
- The control point. The administrator specifies its parameters in advance.
- Lack of free space for writing on the drive. In this case, the answer comes about the lack of free disk space.
- There is a lack of RAM to ensure the operation of buffers. An error appears about the overflow of the RAM buffer and the inability to perform other operations.
- Stopping the database.
When writing directly, the DBMS records any changes in the database to external media in real time. The process resembles synchronous replication.