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Indexes An index of a database table is very much like an index of a book helping you to look up the information that you need. It is an ordered list of all the values in a field (or several fields) of the table, with pointers to the record where each value appears. For example, an index could be an alphabetical list of all the last names in a table, with a pointer to the record in which each name appears. It is faster for Access to look up the last name in the index and then go to the record it points to than to read through every record in the table until it finds the name. The primary key of an Access table is automatically indexed, and Access can use this index to speed up many of its operations. That is why it encourages you so strongly to include a primary key in each table. You can also create indexes for other fields that are used in finds,
query criteria, or sorts. If you create the index, Access uses it
to speed up performance.
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