The entity type is the fundamental building block for describing the structure of data with the Entity Data Model (EDM). In a conceptual model, an entity type represents the structure of top-level concepts, such as customers or orders. An entity key defined by one or more properties.

The business entity concept states that the business is separate from the owner(s) of the business. Therefore the accounting records for even the simplest business, the sole trader, must be kept separate from the personal affairs of the owner or owners.

In simplest terms, a business entity is an organization created by an individual or individuals to conduct business, engage in a trade, or partake in similar activities. There are various types of business entities—sole proprietorship, partnership, LLC, corporation, etc.

A Relationship Type is a type of association that can exist between two different (or same) entity types. For example, a person can manage another person, or an organization can legally own another organization.

An Entity Type defines a collection of similar entities. An Entity Set is a collection of entities of an entity type at a point of time. In ER diagrams, an entity type is represented by a name in a box.

Database entity is a thing, person, place, unit, object or any item about which the data should be captured and stored in the form of properties, workflow and tables.

A strong entity is complete by itself and is not dependent on any other entity type. It possess a primary key which describes each instance in the strong entity set uniquely. A Strong entity is represented by a square with a single line unlike a Weak Entity which contained double lines.

A weak entity is one that can only exist when owned by another one. For example: a ROOM can only exist in a BUILDING. On the other hand, a TIRE might be considered as a strong entity because it also can exist without being attached to a CAR. Just to play with it, question is strong entity type and answer is weak.

Weak entity set is required for following reasons: 1. To avoid the inconsistencies caused by duplicating the key of the strong entity. If we add primary key attributes to the weak entity set, they will be present in both the entity set and the relationship set and they have to be the same.

For each weak entity in the model-there are three: inventory, order, and item-translate the entity directly to a CREATE TABLE statement as in Step 1. Include all attributes as in Step 1. Include as attributes the primary key attributes of the owning entity; that is, the entity the weak entity is related to.

A weak, or non-identifying, relationship exists if the primary key of the related entity does not contain a primary key component of the parent entity. Company database examples include: Customer(CustID, CustName)

An entity relationship diagram describes how entities relate to each other. In simple terms, it’s a picture or a framework of your business or a certain business process. (Learn more about business process modeling). Entities are the things we need to store data about.