Multiple choice technology databases

Which type of entity cannot exist in the database unless another type of entity also exists in the database, but does not require that the identifier of that other entity be included as part of its own identifier?

  1. Weak entity

  2. Strong entity

  3. ID-dependent entity

  4. ID-independent entity
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A weak entity depends on another entity for its existence but has its own partial key, called a discriminator, that distinguishes instances of the weak entity that share the same parent entity. This differs from an ID-dependent entity, which requires the parent's identifier as part of its own composite key. Strong entities exist independently, while ID-independent entities have no dependency.

AI explanation

A weak entity depends on another entity for its existence — it cannot appear in the database unless the related (owner) entity is also present — but unlike an ID-dependent entity, it doesn't need to incorporate the owner's identifier as part of its own primary key. A strong entity, by contrast, can exist independently, which is why that option doesn't fit the description.

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