Partitioning and Aggregating Data in Queries
Abstract
This section is concerned with how to break the data in SQL into meaningful subsets that can then be presented to the user or passed along for further reduction. This is not the same as physical partitioning which moves data to slower storage administrative reasons.
Keywords
Subsets
Partition
Covering
Ranges
Soundex function
NTILE()
This chapter is concerned with how to break the data in SQL into meaningful subsets that can then be presented to the user or passed along for further reduction.
31.1 Coverings and Partitions
We need to define some basic set operations. A covering is a collection of subsets, drawn from a set, whose union is the original set. A partition is a covering ...
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