Theory question 104
Distributed and Parallel DatabasesPaper 2, Essay questions
(a) With reference to database management system, state: (i) one difference between fragmentation and replication. (ii) two advantages of replication. (b) List two: (i) types of fragmentation. (ii) examples of relational database management system.
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(a)(i) Fragmentation splits a table into smaller parts stored at different sites, while replication stores full copies of the same data at several sites.
(ii) Any two: data stays available if one site fails; faster local access/queries; reduced network traffic; load is shared among sites.
(b)(i) Any two: horizontal fragmentation (by rows); vertical fragmentation (by columns); mixed/hybrid fragmentation.
(ii) Any two: Microsoft Access; MySQL; Oracle; Microsoft SQL Server; PostgreSQL.
Fragmentation divides; replication copies.