Relational Database Definition

A relational database stores and organizes data points that are related to one another. Based on the relational database model, a relational database presents data sets as a collection of tables and provides relational operators to manipulate the data in tabular form.

Image depicts a simple diagram of a relational database structure.

 

FAQs

What is a Relational Database?

Relational databases maintain data in tables, providing an efficient, intuitive, and flexible way to store and access structured information. Tables, also known as relations, consist of columns containing one or more data categories, and rows, also known as table records, containing a set of data defined by the category. Applications access data by specifying queries, which use operations such as project to identify attributes, select to identify tuples, and join to combine relations. The relational model for database management was developed by IBM computer scientist Edgar F. Codd in 1970.

 

How do Relational Databases Work?

Relational databases provide an environment from which data can be accessed or reassembled in a variety of different ways without needing to reorganize the database tables. Each table has a unique identifier, or primary key, which identifies the information in the table, and each row contains a unique instance of data for the categories defined by the columns. For instance, the table might have a primary key of ‘First Names’ and rows with specific examples such as ‘John, Paul, George and Ringo.’

The logical connection between different tables can then be established with the use of foreign keys - a field in a table that connects to the primary key data of another table. Relational Database Management Systems often employ SQL or structured query language for gathering data for reports and for interactive queries. So in our example, First Names might be linked to a Role table with data roles of Lead Vocals, Bass Guitar, Drums and Lead Guitar.

 

How is Data in a Relational Database System Organized?

The relational model of the relational database separates logical data structures from physical storage structures, enabling database administrators to manage physical data storage without affecting access to that data as a logical structure. The distinction also applies to database operations -- logical operations allow an application to specify the content it needs, and physical operations determine how that data should be accessed, then carries out the task.

 

What are the Advantages of a Relational Database?

The main advantage of a relational database is its formally described, tabular structure, from which data can be easily stored, categorized, queried, and filtered without needing to reorganize database tables. Further benefits of relational databases include:

  • Scalability: New data may be added independent of existing records.
  • Simplicity: Complex queries are easy for users to perform with SQL.
  • Data Accuracy: Normalization procedures eliminate design anomalies.
  • Data Integrity: Strong data typing and validity checks ensure accuracy and consistency.
  • Security: Data in tables within a RDBMS can limit access to specific users.
  • Collaboration: Multiple users can access the same database concurrently.

 

What is a Relational Database Management System?

A Relational Database Management System is a tabular based collection of programs and capabilities that provides an interface between users and applications and the database, offering a systematic way to create, update, delete, manage, and retrieve data. Most relational database management systems use the SQL programming language to access the database and many follow the ACID (Atomicity, Consistency, Isolation, Durability) properties of the database:

  • Atomicity: If any statement in the transaction fails, the entire transaction fails and the database is left unchanged.
  • Consistency: The transaction must meet all protocols defined by the system -- no partially completed transactions.
  • Isolation: No transaction has access to any other transaction that is unfinished. Each transaction is independent.
  • Durability: Once a transaction has been committed, it will remain committed through the use of transaction logs and backups.

 

What is the Difference Between a Relational and Non Relational Database?

Non Relational Databases, or NoSQL databases, store and organize data in means other than the tabular relations model used in relational databases. Where relational databases store data in rows and columns, have strict rules concerning data variety and table relationships, and follow strict ACID properties, non relational databases offer a more flexible data structure based on the BASE (Basically Available, Soft state, Eventual consistency) model: Basically Available guarantees the availability of the data - there will be a response to any request, but without any consistency guarantee; Soft State guarantees that the state of the system could change over time; and Eventual Consistency guarantees that the system will eventually become consistent once it stops receiving inputs.

 

Does OmniSci Offer a Relational Database Solution?

Analyze relational data structures with the power of OmniSciDB, the foundation of the OmniSci platform. OmniSciDB is open source, SQL-based, relational, columnar and specifically developed to harness the parallel processing power of graphics processing units (GPUs) for interactive visual analytics. OmniSciDB can query up to billions of rows in milliseconds, and is capable of unprecedented data ingestion speeds, making it the ideal SQL engine for the era of big, high-velocity data.