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Why are entity relationship diagrams used?

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Answered 2014-01-08 15:58:30

Entity Relationship (ER) diagrams are drawn when designing a database system, After the systems specification, an ER diagram is drawn showing the conceptual design of the database, this diagram shows the type of information that is to be stored in the system and how these information associate with each other (e.g. one-to-one, one-to-many, etc).

ER Diagrams are simple and easy to understand, thus, this diagram can be shown and explained to user representatives for confirmation and approval.
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What are the advantages and disadvantages of Entity Relationship Diagrams?

Entity-Relationship diagrams are useful for modelling data and the relationships between the data. They can be used when the constraints between data are relatively simple. They do not allow specification of interactions between the data or model how the data changes (there are no processes in Entity-Relationship). Entity-Relationship diagrams are most often used to model databases.

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In software engineering, an Entity - Relationship model(ER model for short) is an abstract and conceptual representation of data. Entity-relationship modeling is a database modeling method, used to produce a type of conceptual schema or semantic data model of a system, often a relational database, and its requirements in a top-down fashion. Diagrams created by this process are called entity-relationship diagrams or ER diagrams.learn more

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Difference between entity attributes and relationship in entity relationship diagram?

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Full form of eer model?


When do you have to use an intersection entity in database?

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An entity relationship diagram for hotel reservation systems is a map of each entity or thing that has a part in the process of hotel reservations. The diagram maps the relationship between each entity of the process.

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What is an entity-relationship diagram?

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What two conditions must be met before an entity can be classified as a weak entity?

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A visual model used to guide the design of a database?

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Difference between Data Flow Diagram and Entity Relationship Diagram?

dfd is generally the flow of data , whereas the entity relationship diagram is the relationship between the entities..

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A common visual model used to guide the design of a database is known as a?

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