The
computer file can be accessed in three modes:
sequential,
random and dynamic.
1.Sequential Access
This
means that for accessing a record sequentially, the file has to be read from
the beginning, that is record 1, record 2, and so on until the required record
is reached. The access time of a single record depends on where in the file the
record is
stored. That is, if it is the first record in the file, it takes much less time
to access than a record that is at the end of the file.
2.Random Access
This
method takes the same time for accessing the record in the file wherever the
record is physically located in the file. The storage location of the record is
obtained by converting the key value of the record into its numeric location
address by hash function. Then the record is located directly.
3.Dynamic Access
This
mode combines both sequential and random modes of access. At times, it may be
required to start sequential access from a given record only. For example a
file holds 2000 records and records numbered 1220 to 1250 are to be accessed
for processing.
In this case, it is better to locate
the record number 1229 randomly and access the remaining records in sequential mode.
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any suggestion on my side