Vertical Fragmentation in Distributed Database System
Vertical Fragmentation (VF)
Each site may not need all the attributes of a relation.
Thus we use vertical fragmentation which divides a relation vertically
by columns.
It is a subset of a relation which is created by a subset of
columns.
A VF of a relation produces fragments R1, R2, …. Rn,
each of which contains subset of attributes of R and PK of R.
Objective is to produce smaller relations, so that most of
the applications run on smaller relations; so they become fast.
Reconstruction of vertical is Join Operation
Î att1,att2,att3…attn
(R)
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