A comparative study of different file organizations to highlight advantages and disadvantages of using different file ORGANIZATIONs for quick reference.
| SEQUENTIAL | INDEXED | RELATIVE |
| Slow when the hit rate is low. | Slowest Direct Access ORGANIZATION. | Wasteful of storage if the file is only partially populated. |
| Complicated to change (insert, delete, amend) | Especially slow when adding or deleting records. | Cannot recover space from deleted records. |
| Most storage efficient. | Not very storage efficient. Must store the Index records, the alternate Index records, the data records and the alternate data records. | Only a single, numeric key allowed. |
| Simple ORGANIZATION. | Can use multiple, alphanumeric keys. | Keys must map on to the range of the Relative Record numbers. |
| Recovers space from deleted records. | Can have duplicate alternate keys. | Fastest Direct Access ORGANIZATION. |
| - | Can be read sequentially on any of its keys. | Can be read sequentially. |
| - | Can partially recover space from deleted records. | Very little storage overhead. |
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