COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Weak
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Strong
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Either A or B
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None of the above
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Detailed explanation-1: -Example of Strong and Weak Entity The Strong Entity is Professor, whereas Dependent is a Weak Entity. ID is the primary key (represented with a line) and the Name in Dependent entity is called Partial Key (represented with a dotted line).
Detailed explanation-2: -An entity is like a unique object and a set of attributes. Talking about the types of entities, we have a strong entity and a weak entity. A strong entity is independent, whereas a weak entity is reliant on another entity.
Detailed explanation-3: -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.
Detailed explanation-4: -A strong entity can be uniquely identified by its own attributes. e.g., a Dormitory can be uniquely identified by its name and location. e.g., a US Bank is uniquely identified by its bank number.