In this section, we will discuss about Sequential file organization. Sequential files have data records stored in a particular sequence. A sequentially organized file might be stored on either a serial-access or a direct-access storage medium.
Structure
In order to provide the 'sequence' required, a 'key' has to be defined for the data records. Generally a field whose values can uniquely identify data records is chosen as the key. If a single field cannot fulfill this criterion, then combination of fields can serve like a key.