Erd \Erd\ ([~e]rd), n. [OE. erd, eard, earth, land, country, AS.
eard; akin to OS. ard dwelling place, OHG. art plowing,
tillage, Icel. ["o]r[eth] crop, and to L. arare to plow, E.
ear to plow.]
The earth. [Prov. Eng.] --Wright.
[1913 Webster]
Erd shrew (Zo["o]l.), the common European shrew (Sorex
vulgaris); the shrewmouse.
[1913 Webster]
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entity-relationship model
entity-relationship diagram
ERD
An approach to data modelling
proposed by P. Chen in 1976. The model says that you divide
your database in two logical parts, entities (e.g. "customer",
"product") and relations ("buys", "pays for").
One of the first activities in specifying an application is
defining the entities involved and their relationships,
e.g. using an entity-relationship diagram to represent a
model.
["The entity-relationship model: toward a unified view of
data", P.P. Chen, ACM Transactions on Database Systems 1:1 pp
9-36, 1976].
(2009-11-21)
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