Relational data model is described as the primary data model, which is used broadly around the world for data storage and processing.
Structure of Relational Data Model
1. Tables: Tables houses, stores or saves relations among entities. A table has rows and columns, where rows represent records and columns represent the attributes.
2. Tuple: Tuple is a single row of a table which holds a single record for that relation.
3. Relation instance: This is represented by a finite collection of tuples in the relational database system. It does not have duplicate tuples.
4. Relation schema: A relation schema defines the relation name (table name), attributes, and their names.
5. Relation key: Each row has one or more attributes, known as relation key, which can identify the row in the relation (table) uniquely.
6. Attribute domain: Every attribute has some predefined value scope, known as attribute domain.
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