At a high level, the term SQL database is used to describe a database that uses the structured query language (SQL) to view and update the data that a Relational Database Management System (RDBMS) manages.
What is a SQL database?
A SQL database uses the notion of related tables made up of rows and columns. Tables are related to each other through primary and foreign key relationships. The RDBMS can enforce these relationships if they are defined using referential constraints. For example, you might set up a defined constraint that no employee record can exist without having a department. This declarative approach makes defining relationships between objects easy and maps well to the application entity-relationship model used to map applications to their respective data layout.
How to Create a SQL Database
The process to create a SQL database can be as easy as installing it on a system. Vendors such as Actian and Microsoft provide installers for Windows and Linux that create a sample database with demo data, making it easy to verify the install and test client connectivity. Some installers create a running instance that accepts a CREATE DATABASE command to define database schema.
Once you have a basic on-premise or cloud-based database instance running, you can create objects such as tables, indexes and views using SQL statements, including CREATE TABLE, CREATE VIEW, and CREATE INDEX. Most database systems support role-based security, which means you can create named permissions groups such as Database Administrator, Application Admin and App User. These named permissions can include statements such as GRANT DELETE ON TABLE-A, which allows records to be deleted from TABLE-A. Permissions can be removed using the REVOKE statement. Next, the DBA would create users or groups of users and grant them privileges to access database objects.
Examples of SQL Databases
Many database systems in use today can be accessed using key-values, which used to be known as indexed-sequential access. Examples of databases that can be accessed using key-values include MongoDB, Amazon DynamoDB, Redis and Actian Zen.
Which one is Best?
There are lots of SQL databases from which to choose. The one that may be best for you depends on a multitude of factors, including the following:
These are just some factors to consider when making a database selection. Enterprise Architects in larger organizations often look at the entire application stack. They are factoring in supportability, observability, scalability, and security when deciding on their next-generation applications platform.
Just picking the easiest or cheapest database solution to get started can land your business with an expensive migration project when you fail to look under the covers as to where the technology came from and whether it is currently being maintained and supported by your vendor of choice. To get more information on all Actian data products and solutions, visit our website.