Chapter 42. Additive Congruential Generators
In many applications, we do not want to issue the numbers in sequence. This pattern can give information that we do not wish to expose. Instead, we want to issue generated values in random order. Do not get mixed up; we want known values that are supplied in random order and not random numbers. Most random-number generators can repeat values, which would defeat the purpose of this drill.
While I usually avoid mentioning physical implementations, one of the advantages of random-order keys is to improve the performance of tree indexes. Tree structured indexes, such as a B-Tree, that have sequential insertions become unbalanced and have to be reorganized frequently. However, if the same set of keys is presented ...
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