Physical Database Design

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Basic Indexing Methods

If you don’t find it in the index, look very carefully

through the entire catalogue.

—Sears, Roebuck, and Co., Consumer’s Guide, 1897

he concept of indexing for dictionaries, encyclopedias, book manuscripts, catalogs,

and address lists has been around for centuries. Methods like tabs in a book volume

or lists of index terms at the back of the book are used very effectively. When a com-

puter needs to find data within a relational database it has exactly the same need. How

can a small amout of data be found from within a very large set without “looking very

carefully through the entire thing catalog.” For example, consider how inefficient life

would be if every time you walked over to an ATM machine to withdraw money the

bank ...