Can someone please explain this statement: At the logical level where there can be any number of entities in a relationship while physically you define relationships between two tables.
thx,
Kat
Take a n-m relation, an example would be a student entity and an lecture entitiy. A student can visit n lectures and a lectures can be visited by n students. Although the tables (entities) cannot be directly be related (only through the n-m table) the pure relation only exists between the students and the lectures entity. its the definition of an entity which make the difference between the understanding.
HTH, Jens K. Suessmeyer.
http://www.sqlserver2005.de
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