DBMS (Database Management System)

What is a Database Management System? Definition from Techopedia

What is a Database Management System (DBMS)?

A simple database management system (DBMS) definition is middleware that allows programmers, database administrators (DBAs), software application, and end users to store, organize, access, query, and manipulate data in a database.

Techopedia Explains the DBMS Meaning

In the enterprise, database management systems provide database administrators (DBAs) with a structured framework that facilitates data sharing among different departments, teams, and applications. The DBMS provides employees with controlled and organized access to data that they can use to drive innovation and help their company maintain a competitive edge.

History of Database Management Systems

The history of database management systems dates back to the early 1960s when computers began to be used for data processing. At that time, the concept was usually referred to as an information management system.

The first commercially available database management system was the Integrated Data Store (IDS). It was developed by Charles W. Bachman and his team at General Electric (GE) in the late 1960s.

IDS was a hierarchical DBMS that organized data in a tree-like structure, with parent-child relationships between records. It allowed users to store, retrieve, and manage data in a structured manner. IDS also introduced the concept of the data dictionary, which defined the structure and relationships of the data within the database. Prior to IDS, data was usually stored in flat files, and there was no standard for how the files should be stored, accessed, or manipulated.

Bachman’s IDS was eventually overshadowed by the emergence of relational databases and the Structured Query Language (SQL) in the 1970s. Since that time, DBMS products and services have undergone continuous advancements that have improved data storage, retrieva, and management.

Evolution of Database Management Systems

Year	Event
1964	Development of the first database, an Integrated Data Store (IDS), by Charles Bachman at General Electric.
1966	IBM introduces the Information Management System (IMS), a joint development with Rockwell and Caterpillar.
1970	Edgar F. Codd introduces the relational model in a paper titled “A Relational Model of Data for Large Shared Data Banks“.
1974	The Structured Query Language (SQL) is created.
1976	Peter Chen introduces the Entity-Relationship Model in his paper “The Entity-Relationship Model – Toward a Unified View of Data“.
1979	Oracle releases the first commercial relational database that uses SQL.
1980	IBM introduces System R, the SQL-based relational database management system.
1981	SQL/DS, the first full-function DBMS to run on personal computers, is released by IBM.
1983	The first version of DB2 by IBM is released for mainframes.
1986	The Object-Oriented Database System Manifesto is published, giving a significant push to the development of object-oriented databases.
1996	PostgreSQL, one of the first open-source relational database management systems is launched.
1998	MySQL, another significant open-source RDMS, is released for Windows 95 and NT.
1998	Microsoft launches SQL Server 7.0, a complete rewrite of their DBMS.
2000	Internet startups embrace XML databases.
2004	The term “NoSQL” gains popularity, leading to a new generation of non-relational, distributed databases.
2006	Google publishes a paper on BigTable, its internal NoSQL database, influencing a new wave of open source NoSQL databases
2012	Amazon introduces DynamoDB, a proprietary NoSQL database.
2013	FoundationDB, a distributed database designed to handle large volumes of structured data, is released.
2017	Google announces Spanner, a globally distributed database.
2020s	Continued development and innovation in DBMS technology, with a focus on cloud-native databases, edge databases and improvements in artificial intelligence (AI) integration for database management. Blockchain databases also become a significant topic of interest.

DBMS Components

The core component of every DBMS is called the database engine. It is the software that interacts directly with the underlying storage system or file system and orchestrates the interactions between modular sub-components that enable the engine to manage and manipulate data in the database system. This includes modules for:

Backup and Recovery

These modules manage data backup and recovery operations to protect against data loss or system failures. They include mechanisms for creating database backups, restoring data, and performing recovery operations.

Concurrency Control and Transaction Management

These modules manage concurrent access to the database by multiple users or applications. They handle locking mechanisms and ensure data consistency.

Database Access Language

This type of module allows the database engine to process and interpret user queries or commands written in the default access language. It analyzes the query language syntax, validates the query against the catalog information, and generates an optimized execution plan to retrieve or manipulate the data as requested.

Data Definition Language (DDL)

The DDL module allows users to define the structure and organization of the data. It includes commands for creating, altering, and deleting database objects such as tables, views, indexes, and constraints.

Data Dictionary

The data dictionary (also called the metadata repository) stores metadata about the database, including information about the data’s structure, relationships, and properties. This module is used by the DBMS engine to ensure data consistency and enforce unique constraints.

Data Manipulation Language (DML)

The DML module provides commands for manipulating and retrieving data within the database. Users can use DML statements to insert, update, delete, and query data.

Data Warehousing and Business Intelligence

These modules facilitate data extraction, transformation and loading from multiple sources into a separate data warehouse. They also support online analytical processing (OLAP) and reporting tools for business intelligence (BI).

Indexing

Most DBMSs include indexing modules to speed up query execution by reducing the amount of data that needs to be scanned.

Locking

The lock manager component of a DBMS is responsible for managing concurrency control. It prevents conflicts and maintains data consistency by ensuring that multiple users or transactions cannot modify the same data simultaneously.

Logging and Auditing

DBMSs often include modules for database logging and auditing activities. Log records document changes to the database – including inserts, updates, and deletions – as well as system events such as backups and recoveries. Auditing involves monitoring and reviewing these logs to track user actions, maintain data integrity and help enforce security policies’ compliance.

Processing Queries

The query processor receives and interprets user queries, converts them into an optimized execution plan, and interacts with the database engine to execute queries efficiently. It includes sub-modules for optimizing queries that consider factors such as available indexes, join operations, and data access methods.

Replication

Some DBMSs support data replication, which involves creating and maintaining multiple copies of the database in different locations or on different servers. Replication improves data availability, fault tolerance, and performance. It ensures that if one copy of the database becomes unavailable, the data can still be accessed from another copy.

Security and Authorization

The security and authorization modules control user access to the database and ensure data privacy and integrity. They handle authentication, and user management, and implement th principle of least privilege (PoLP) access control mechanisms based on user roles and job requirements.

Storage

The database engine in a DBMS communicates with a storage engine to manage physical data storage. The storage engine is responsible for handling the low-level details of how data is stored and accessed, while the database engine coordinates and orchestrates these actions to optimize the overall functioning of the database management system.

User Interfaces

These modules provide user interfaces (UI) that allow programmers, database administrators, and end users to interact with the database. This can include command-line interfaces (CLI), graphical user interfaces (GUI), or application programming interfaces (APIs) for software integration.

User Policies

User policies define and enforce access controls and internal security policies. They specify permissions, roles, and privileges and govern how users can interact with a database.

Database vs. DBMS

The terms “database” and “database management system” are often used interchangeably in casual conversations. That’s probably because when end users interact with a database, they are not aware of the underlying DBMS and its distinct role in managing data. To add to the confusion, in some cases, the DBMS is embedded directly into the application code, making it even less apparent that a separate system is involved.

To differentiate between the two terms and use them correctly, it’s helpful to understand their respective roles and functionalities:

A database is a structured collection of data.
The database management system is the software that developers, end users, and applications use to interact with a database.

RDBMS vs. DBMS

A relational database management system (RDBMS) is a type of database management system. All RDBMSs are DBMSs, but not all database management systems are relational database management systems.

DBMS	RDBMS
Different types can be used to manage various types of database models	Can only manage the relational database model
Data can be stored in diverse structures depending on the type of DBMS used	Always stores data in tables with rows and columns
The automatic enforcement of data integrity may vary across different types of DBMS	Automatically enforces data integrity through constraints such as primary key, unique key, and foreign key
Different DBMS types can use different languages or techniques for manipulating data	Always uses SQL

Types of Database Management Systems

Until the turn of the century, database management systems were classified as either relational or non-relational, depending on their structure and uses. If the DBMS stored data in tables, it was referred to as a relational DBMS (RDBMS). If it did not store data in tables, it was referred to as a NoSQL or non-relational DBMS.

Today, database management systems are still categorized as being either RDBMS or non-RDBMS, but they are also classified by the unique advantages they provide. Types of DBMSs include:

Cloud Database Management Systems

Cloud DBMSs like Amazon Aurora are designed to manage distributed data stored in a cloud provider’s remote data centers.

Columnar Database Management Systems

Columnar DBMSs like Apache Cassandra return queries faster by storing data in columns instead of rows. This schema makes it easier for data analytics and business intelligence applications to work with large datasets.

Distributed Database Management Systems

DDBMS functionalities like those found in the Apache Hadoop ecosystem are designed to ensure data integrity for logically related databases across multiple locations or computing environments.

Graph Database Management Systems

These systems are designed to support graph databases that store relationships at the individual record level. Graph DBMSs like Neo4j are ideal for managing data with interconnected relationships, such as social media data.

Hierarchical Database Management Systems

Hierarchical management systems are designed to support databases organized in parent-child relationships. This type of DBMS has its roots in mainframe computing and its uses today are limited.

HTAP Database Management Systems

Hybrid transaction/analytical processing DBMSs are designed to support mixed workloads for transactional and analytical data. Traditional database systems often have separate systems for online transaction processing (OLTP) and online analytical processing (OLAP) workloads. HTAP management systems like SAP HANA and CockroachDB provide a unified platform that can handle both types of tasks concurrently.

In-memory Database Management Systems

In-memory management systems are designed to reduce latency by using main memory for data management and storage. Volt Active Data and other IMDBMSs make data retrieval significantly faster and improve overall system performance.

Object-oriented database management system (OODBMS)

db4o is one example of this type of DBMS. OODMBSs are designed to manage complex data structures as storage objects.

NewSQL Database Management Systems

NewSQL DBMSs like PostgreSQL provide the scalability and performance benefits of NoSQL databases while retaining the ACID properties of traditional relational databases. This type of DBMS is designed for large-scale distributed environments and can handle high-throughput transactional workloads.

Time-Series Database Management Systems

Time-series DBMSs like InfluxDB optimize the storage, retrieval, and analysis of time-stamped data. They are often used to support financial analytics and Internet of Things (IoT) monitoring systems.

Database Management Systems Example

Examples of well-known DBMSes include:

	Access – a lightweight RDMS included in Microsoft Office and Office 365.
	Amazon RDS – a native cloud DBMS that offers engines for managing MySQL, Oracle, SQL Server, PostgreSQL and Amazon Aurora databases.
	Apache Cassandra – an open source distributed database management system known for being able to handle massive amounts of data.
	Filemaker – a low-code/no-code (LCNC) relational DBMS.
	Google Cloud Spanner – a globally distributed, horizontally scalable, and strongly consistent relational database service offered by Google Cloud.
	IBM Db2 – a family of relational database management systems developed by IBM that offers various editions for different environments and workloads.
	MariaDB – an open source relational database fork of MySQL.
	Microsoft Azure SQL Database – a cloud-based relational database service provided by Microsoft Azure that offers fully managed SQL databases.
	MongoDB – A popular NoSQL database management system that uses a document-oriented schema to provide high scalability and flexibility.
	MySQL – an open source RDBMS owned by Oracle.
	Oracle – a proprietary RDMS optimized for hybrid cloud architectures.
	PostgreSQL – an open source relational database management system known for its robustness, scalability, and extensive feature sets.
	SAP HANA – an in-memory, column-oriented RDBMS optimized for real time data ingestion and high-performance analytics.
	SQL Server – an enterprise-level relational database management system from Microsoft that is capable of handling extremely large volumes of data and database queries.
	SQLite – a lightweight, file-based relational database engine that is widely used in embedded systems and mobile applications.
	Teradata – a powerful SQL engine that provides scalable solutions for managing and analyzing large volumes of data.

Benefits of Using a DBMS

Concurrency controlSecurity featuresCompliance supportData lifecycle managementPrivacy controls

Manages interactions between multiple users or applications accessing the same database simultaneously, ensuring data integrity in high-traffic scenarios.

Offers a variety of security features such as access control rules, user role assignments, and permission settings to safeguard data from unauthorized access or manipulation.

DBMSs are useful compliance tools because they provide audit trails and logging capabilities to track and monitor data access use and modifications.

A DBMS can help admins manage data lifecycle management by implementing policies for data retention, archival, and eventual disposal. A DBMS can also help enforce privacy controls by providing mechanisms that anonymize or encrypt sensitive data.

Enforces privacy measures through mechanisms like data anonymization or encryption to protect sensitive information from unauthorized disclosure.

Challenges of Database Management Systems

Although database management systems have revolutionized the way small and large businesses handle and manage data, the learning curve for enterprise DBMS implementation and management can be challenging. This is especially true if the DBMS needs to be integrated with enterprise resource planning (ERP) systems or customer relationship management (CRM) platforms.

Rolling out a new DBMS can also be expensive. Even mid-size businesses will most likely need to hire or contract with a skilled database administrator to ensure their DBMS is properly configured, maintained, and optimized. Licensing fees, hardware infrastructure, software upgrades, and ongoing maintenance expenses can also strain budgets, especially for smaller organizations.

Future of the DBMS

Today’s DBMSs incorporate cutting-edge technologies such as AI, machine learning (ML), and blockchain to tackle the challenges of big data and help organizations stay compliant with relevant regulations and standards for data management.

DBMSs equipped with AI and ML capabilities can automate tasks such as query optimization, data indexing, and anomaly detection. Intelligent database management systems can learn from data patterns, adapt to changing workloads, and optimize performance autonomously.
Blockchain-enabled databases can provide immutable, transparent data storage and enable secure, auditable transactions. This type of database management system eliminates the need for central authorities while still enhancing data integrity. It makes them ideal for industries like finance, supply chain, and healthcare, where the risks and impacts of data tampering are significant.
DBMSs with built-in stream processing capabilities are becoming vital for use cases like real-time analytics, fraud detection, and personalized customer experiences. With the rise of the IoT and streaming data sources, DBMSs will need to handle real time data processing even more efficiently.