
Distributed Database Design
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V1: Π
Project-id, branch-no, project-leader-id
(Project)
V2: Π
Project-id, Project-name, Project-type, amount
(Project).
Hence, primary key for the relation Project is Project-id, which is repeated in both vertical frag-
ments V1 and V2 to reconstruct the original base relation from the fragments.
Hence, vertical fragmentation also ensures the correctness rules for fragmentation.
Completeness – Each attribute in the relation Project appears either in fragment V1 or V2,
which satisfi es the completeness rule for fragmentation.
Reconstruction – The Project relation can be reconstructed from the vertical fragments V1
and V2 ...