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Revision (Networks (protocols, LAN's, WAN's, circuit switching,…
Revision
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Databases
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primary key
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In a relational database, this is known as a Primary Key.
So far, none of the attributes we’ve talked about are suitable for a Primary key.
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In the entity description, the primary key is underlined:
Dentist(DentistID, Title, Firstname, Surname, Qualification)
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foreign key
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Where a relationship exists between entities, an extra field known as a Foreign Key links the two tables.
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