A file where each records is of the same length is said to have fixed length records.

Some fields are always the same length (eg Postcode is always 7 characters).

 Some fields may need to be 'padded out' so they are the correct length 
(eg Surname - If 15 characters are stored then Jenkins would be stored as 'JENKINS        ' - 7 characters followed by 8 spaces).

Advantage : Access is fast because the computer knows where each record starts. It follows that processing all the data in a file will be fast.

Eg If each record is 120 bytes long then

• the 1st record starts at [Start of File] + 0 bytes
• the 2nd record starts at [Start of File] + 120 bytes
• the 3rd record starts at [Start of File] + 240 bytes etc.....

Disadvantage : Using Fixed length records, the records are usually larger and therefore need more storage space and are slower to transfer (load or save) or transmit down a network.

Example : Any information retrieval system (Eg Train time-table program) where information needs to be accessed quickly.

In the Example

...the field lengths (in bytes) may be defined as ...

Number :	5
Surname:	15
Forename:	15
Year:	2
Form:	1
DOB:	8

Each record would be 46 bytes long.

The first record of the example file would be stored as ...(each box represents one byte of storage)..