Inversion List

An inversion list is part of an index. An inversion list consists of a secondary key and the related primary key(s).

A table contains the names of all customers in a hotel. Customer number cno is the primary key for this table.

Now you define an index for the name column. The name column thus becomes an indexed column (also called an inverted column).

The index contains the following inversion lists:

An inversion list with the secondary key Griffith and the primary key 2011 (the surname Griffith only appears once in the table)
Another inversion list with the secondary key Miller and the primary keys 2003, 2078, 2104, and 2295 (the surname Miller appears four times in the table)