nData are represented by collections of records.
lsimilar to an entity in the E-R model
lRecords and their fields are represented as record type
type customer = record type account = record
customer-name: string; account-number: integer;
customer-street: string; balance: integer;
customer-city: string;
end end
nRelationships among data are represented by links
lsimilar to a restricted (binary) form of an E-R relationship
lrestrictions on links depend on whether the relationship is many-many, many-to-one, or one-to-one.
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