Conceptual data model

Conceptual data model is a map of key concepts and rules binding these key concepts for a specific business, for a particular audience, that used for databases. Key concepts are both basic and critical to your business. Basic means this term is mentioned many times a day in your organisation in conversation among business people, such as CUSTOMER, EMPLOYEE, PRODUCT, etc.Critical means the business would be very different or non-existent without this key concept. For example, without the concept PRODUCT, your business may become non-existent.

Keys in data modeling

In data modeling, we use keys for data retrieval and easy navigation. In this post we are going to discuss about the different keys used in data modeling such as candidate keys, composite keys, primary keys, alternate keys, surrogate keys and foreign keys and their important.

Relationships and Cardinality

In real world, entities have relationships with other entities.  Relationships define how two entities are associated with each other. The data modeling captures the nature of relationship between two entities. For example, the entity 'Customer' buys the 'Product' and the entity 'Vendor' sells the 'Product'. It captures the rules between these two entities. If two entities are Person and Telephone Number, the relationship may capture the rule "Each Person may have many Telephone Numbers" and "Each Telephone Number must belongs to one Person." 

Data fields and domains

In previous post we have seen about the entities, in this post let us see about the data fields and domains. Data field is nothing but a column header or label describing instances of an entity. The data field Customer Name describes name of each Customer. The data field Model Number identifies each model.


An entity represents a collection of information about something that the business deems important and worthy of capture. A noun identifies a specific entity. Usually an entity fits into one of several categories - who, what, when, where, why, or how.

Uses of data model

Traditionally, data models are created to ensure that the requirements for a new applications are fully understood and correctly captured before the actual database is created. Usually data models are created during the analysis and designing phases of a project.