Discuss the relative benefits and drawbacks of the following file organization methods: a. sequential b. indexed-sequential c. direct

What will be an ideal response?

Answer: Suggested answer:

a. Sequential: This method has the advantage of utilizing storage space on a disk or tape most efficiently, which is especially crucial for very large files. The method's main disadvantages are the requirement for all files to be sorted (or in sorted order) prior to processing and to access each record in sequence. The latter can be time-consuming, thus making quick response impossible.
b. Indexed-sequential: This method has the advantage of sequential organization discussed above. In addition, due to the use of an index to locate files, this method also allows for accessing individual records quickly. The index is useful when a quick response time is needed or a low-activity application is used. This method is most appropriate for both high-activity and low-activity uses. Indexed-sequential organization uses more storage space then sequential organization because the indexes take up extra space.
c. Direct: This method has the fastest response time due to the use of a randomizing transaction to locate individual records. However, this method also can lead to large amounts of wasted storage space depending on the particular algorithm that is used.