partitioning the keys into j term partitions and having the parsers write keyvalue
pairs for each term partition into a separate segment file. In Figure 4.5,
the term partitions are according to first letter: a–f, g–p, q–z, and j = 3. (We
chose these key ranges for ease of exposition. In general, key ranges need not
correspond to contiguous terms or termIDs.) The term partitions are defined
by the person who operates the indexing system (Exercise 4.10). The parsers
then write corresponding segment files, one for each term partition. Each
term partition thus corresponds to r segments files, where r is the number
of parsers. For instance, Figure 4.5 shows three a–f segment files of the a–f
partition, corresponding to the three parsers shown in the figure.