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Sorted Runs :
Consider a cuboid on j attributes {
}. We use
(
)
to denote cuboid sorted in that order. Consider
computed using
.
A sorted run R of S in B is defined as :
,
where Q is the
maximal sequence of tuples t of B such that for each tuple in Q, the first
l columns have the same value.
Partitions :
B and S have a common prefix
.
A partition of a
cuboid S in B is a union of sorted runs such that the first l - 1 columns
(the common prefix) of all the tuples of the sorted runs have the same
value.
DBMS
1999-04-01