March 2022
Intermediate to advanced
682 pages
22h 58m
English
Content preview from Databases Illuminated, 4th Edition
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4.4 Representing Relational Database Schemas
A relational database schema can have any number of relations. We can represent relation schemas by giving the name of each relation, followed by the attribute names in parentheses, with the primary key underlined. The database schema also includes domains, views, character sets, constraints, stored procedures, authorizations, and other related information, so our representation is only a part of the schema.
The standard way of showing foreign keys is by drawing arrows from the foreign keys to the primary keys they refer to. We will use italics to indicate that an attribute is a foreign key, or part of a foreign key, and add a line specifying the attribute it corresponds to in the home relation. For ...
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