access method

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access method Any algorithm used for the storage and retrieval of records from a data file or database. Access methods are of two kinds: those that determine the structural characteristics of the file on which it is used (its file organization) and those that do not (as in secondary indexing (see indexed file) and data chaining). In the first case essentially the same algorithm is used for the retrieval of a record as was used for its original physical placement, whereas in the second these algorithms are quite distinct. Hence in the first case the same term may be used interchangeably (and loosely) for both the access method and the file organization (see random access (def. 2), sequential access).