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- Entity
E-
a row inside a database table.
- Reference (E1, E2) - ordered
pair of two Entities E1and E2.
- Association-
symetrical set of references. (E1, E2) <=> (E2, E1)
- Join conditionJC of Association A - specifies an association
between two tables:
A:={(E1, E2(|E1?T1, E2?T2, JC(E1,
E2) or JC(E2, E1)}
- Restriction
on an Association A -
subset of A.
- Restriction
condition
RC - specifies a
restriction R on A: R:={(E1,
E2)|{E1,
E2}?A, RC(E1,
E2)}
- Subject -
set of Entities to be exported.
- transitive closure
of S - smallest set containing S and all entities referenced by an
entity inside the closure. The transitive closure of the subject according
to the resticted associations is exactly the set that Jailer will
export.
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