Data Set (IBM Mainframe)

Data Set (IBM Mainframe)

data set (archaic), dataset (preferred), is a computer file having a record organization. The term pertains to the IBM mainframe operating system line, starting with OS/360, and is still used by its successors, including the current z/OS. Those systems historically preferred this term over a file. A dataset is typically stored on direct access storage device (DASD) or magnetic tape, however unit record devices are also supported.

Datasets are not unstructured streams of bytes, but rather are organized in various logical record and block structures determined by the DSORG (data set organization), RECFM (record format), and other parameters. These parameters are specified at the time of the data set allocation (creation), for example with the Job Control Language DD statements. Inside a job they are stored in the Data Control Block (DCB), which is a data structure used to access datasets, for example using access methods.

Read more about Data Set (IBM Mainframe):  Dataset Organization, Record Format (RECFM), Partitioned Datasets

Famous quotes containing the words data and/or set:

    This city is neither a jungle nor the moon.... In long shot: a cosmic smudge, a conglomerate of bleeding energies. Close up, it is a fairly legible printed circuit, a transistorized labyrinth of beastly tracks, a data bank for asthmatic voice-prints.
    Susan Sontag (b. 1933)

    Reason is natural revelation, whereby the eternal father of light, and fountain of all knowledge, communicates to mankind that portion of truth which he has laid within the reach of their natural facilities: Revelation is natural reason enlarged by a new set of discoveries communicated by God immediately, which reason vouches the truth of, by the testimony and proofs it gives, that they come from God.
    John Locke (1632–1704)