Glossary

access   The operation of seeking, reading, or writing data on a storage unit.

access method   A technique used to transfer a physical record from or to a mass storage device.

access mode   A technique in which a specific logical record is obtained from or placed onto a file assigned to a mass storage device.

access pattern   The general sequence by which the data structure is accessed (such as from tuple to tuple, from record to record, from segment to segment, and so on).

access   Plan the control structure produced during program preparation and used by a database manager to process SQL statements during application execution.

access time   The time interval between the instant an instruction initiates a request for data and the instant the first of the data satisfying the request is delivered. Note that there is a difference—sometimes large—between the time data is first delivered and the time when all the data is delivered.

accuracy   A qualitative assessment of freedom from error or a quantitative measure of the magnitude of error, expressed as a function of relative error.

active data dictionary   A data dictionary that is the sole source for an application program insofar as metadata is concerned.

activity   (1) The lowest-level function on an activity chart (sometimes called the “atomic level”); (2) a logical description of a function performed by an enterprise; (3) a procedure (automated or not) designed for the fulfillment of an activity.

activity ratio   The ...

Get Corporate Information Factory now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.