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Week 2 Discussion - The Entity Relationship Model

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Defining  relationships within a database can improve search capabilities and  optimal performance of the database in the long run.

• Identify at least two relationship strength types that can be used within the entity relationship model.
• Provide a real-world scenario that demonstrates each relationship strength classification, using the classifications.
• Be sure to respond to at least one of your classmates' posts.

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Afolabi Ajagbe         

 1:44pm Apr 15 at 1:44pm          

Hello,

An entity in DBMS (Database Management System) is something genuine  and this is a real-world object with attributes, which describe the  entity's characteristics. A person, for instance, is an entity with  characteristics like name, age, gender, and so on.

In the schema, a strong entity is independent of any other entity. A  strong element will constantly have an essential key. A strong entity  set is a set that is comprised of serious areas of strength for numerous  and is addressed by a single rectangle shape. The connection that  exists between two powerful entities is symbolized by a single diamond.  Notwithstanding, in the event that the relationship is between a strong  entity and a weak entity, the relationship is addressed by a double  diamond shape.

A weak entity in DBMS is an entity whose presence relies upon a  stronger entity for strength and it doesn't have its very own essential  key. A weak entity is addressed by a twofold rectangle shape.

I recollect half a month prior, I was arranging an excursion to  another state and called Lodgings Focal booking registry to assist me  with finding a close-by inn to the city downtown. The booking agent was  able to find a good hotel, check if they had rooms available on the days  I needed to stay there, and then finalize and book the room for me.

This is a modeling of actual entity-to-entity relationships.

1. Hotels represent a "Strong Entity"
2. Rooms represent a "Week Entity"

Their relationship existed such that without the Hotel there could not be hotel rooms.