Describe sequential and random methods of file organisation. Sequential file organisation Random file organisation

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2023). The mark or mark type is shown in brackets.

1. [1] One mark per mark point – sequential (Max 2)
2. [1] MP1 Records (in the file) are ordered
3. [1] MP2 ...based on the key field
4. [1] MP3 A new version (of the file) has to be created to update the file
5. [1] One mark per mark point – random (Max 2)
6. [1] MP4 Records are stored in no particular order within the file // There is no sequencing in the placement of the records
7. [1] MP5 There is a relationship between the key of the record and its location within the file // a hashing algorithm is used to find the location of the record
8. [1] MP6 Updates to the file can be carried out directly.
9. [1] One mark per mark point (Max 2)
10. [1] MP1 Start at the beginning of the file
11. [1] MP2 ...check records linearly
12. [1] MP3 ...until the desired record is found // processing / updating records as required //... EOF found.