A composite primary key<span> is a set of several primary </span>keys<span> that, together, uniquely identifies each record.</span>
Primary keys are used as identifiers of composite entities. In this case each primary key combination is allowed only once in the *:* relationship.
Other case where primary keys are used is as identifiers of weak entities, where the weak entity has a strong identifying relationship with the parent entity.
Answer:
C. Appliance.
Explanation:
When a device or machine performs a single function or task, it is commonly referred to as an appliance. Examples of such is an iron, a calculator, a computer game, washing machines, refrigerators, e.t.c
<em>A Personal Digital Assistant (PDA)</em>, is a device, mostly mobile and handheld, that combines various computing features such as telephoning and networking. An example is a tablet. A PDA performs more than a single function.
<em>Minicomputer</em> is a computer usually small in physical size, that is midway in capabilities and support, between a microcomputer and a mainframe computer. An example is also a tablet and our smartphones. Minicomputers are also dedicated to various functions rather than a single function.
In summary, the option that best describes the situation in the question is an appliance.
<em>Hope this helps!</em>
Max()
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Answer:
D) All of the above
Explanation:
All of these options are true.
Hope it helps and is correct!
