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QuoteRef: chenPP3_1976
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ThesaHelp:
ACM references a-e
ThesaHelp:
references c-d
Topic:
attribute-value pairs as information
Topic:
database keys and indexing
Topic:
entities
Topic:
entity-relationship database model
Topic:
database as a model of reality
Topic:
Thesa data model
Topic:
data as a named set of data objects
Topic:
object and value equivalence
Topic:
data types in Thesa
Topic:
type conversion
Topic:
units
Topic:
name of a relationship
Reference
Chen, P.P.-S., "The entity-relationship model--toward a unified view of data", ACM Transactions on Database Systems, 1, 1, pp. 9-36, March 1976. Google
9 ;;Quote: the real world consists of entities and relationships; basis for entity-relationship model
12 ;;Quote: observed or measured information about an entity or relationship is expressed as a set of attribute-value pairs
12 ;;Quote: units define equivalent values between two value sets QuoteRef: chenPP3_1976 ;;14 entities: employee with attributes employee-no. Name, age relationship: project-worker with attribute percentage of time QuoteRef: chenPP3_1976 ;;14 "Basically, an entity key is a group of attributes such that the mapping from the entity set to the corresponding group of value sets is one-to-one
16 ;;Quote: since a relationship is identified by the involved entities, can use their keys for the relationship key
ThesaHelp: ACM references a-e (259 items)
ThesaHelp: references c-d (337 items)
Topic: attribute-value pairs as information (53 items)
Topic: database keys and indexing (18 items)
Topic: entities (20 items)
Topic: entity-relationship database model (21 items)
Topic: database as a model of reality (25 items)
Topic: Thesa data model (58 items)
Topic: data as a named set of data objects (22 items)
Topic: object and value equivalence (60 items)
Topic: data types in Thesa (92 items)
Topic: type conversion (33 items)
Topic: units (23 items)
Topic: name of a relationship (5 items)