-Person, place, object, event, concept, etc. (Noun) Show -Entity type vs. entity instance (Table vs. Row) type: should be: -An object that will be composed of multiple attributes -An object that we are trying to model Should not be: -An output of the database system (e.g., a report) What are characteristics or properties of an entity called?Attribute. A characteristic or trait of an entity type that describes the entity, for example, the Person entity type has the Date of Birth attribute.
What are the types of entity?An entity can be of two types :. Tangible Entity : Entities that exist in the real world physically. Example: Person, car, etc.. Intangible Entity : Entities that exist only logically and have no physical existence. Example: Bank Account, etc.. Is an attribute that uniquely identifies individual instances of an entity type?The primary key is an attribute or a set of attributes that uniquely identify a specific instance of an entity. Every entity in the data model must have a primary key whose values uniquely identify instances of the entity.
What is entity and entity type?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 type is a template for entity type instances.
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What is a property or characteristic of an entity or relationship type that is of interest to the Organisation?
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