Meaning – The term relation, refers to a set of entity occurrences that have the same attributes. The relation is sometimes used to refer to a table in a relational database but is more commonly used to describe the relationships that can be created between those tables in a relational database.
In relational databases, a relationship exists between two tables when one of them has a foreign key that references the primary key of the other table. This single fact allows relational databases to split and store data in different tables, yet still link the disparate data items together.
In a relational database, the term relation refers to a table that identifies entities and their attributes.
Example of usage – “The ability to define relationships is so fundamental and so important that this is what differentiates relational databases from other types of databases, such as flat-file databases. Relation, therefore, is the defining feature of relational databases.”