b_book1.gif (162 bytes)Data - Organisation | Data processing
b_html2.gif (189 bytes)Examples

Sequential file

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Features

  • Records are held in the file in a defined sequence, based on the value of key field(s) in each record.
  • Access is sequential.
  • Records may be variable in length
  • Typically used on magnetic tape

Examples:

Advantages
  • High hit rate for sorted access
  • Can use tapes which are inexpensive
  • Relates well to manual systems
 Disadvantages
  • Not instant (Must be rewound to start for a search).
  • Poor for random access
  • Updates must be sorted
  • Time consuming

Operations:

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[Rev 18/01/99] 2/7/97 © 1997-99 V/2-Com (Verhaart), P O Box 8415, Havelock North, New Zealand.