Explain the following three types of pointers: physical address pointer, relative address pointer, and logical key pointer
A physical address pointer contains the actual disk storage location (cylinder, surface, and record number) needed by the disk controller. This approach allows the system to access the record directly without obtaining further information.
A relative address pointer contains the relative position of a record in the file. This address (i.e., the 200th record on the file) must be further manipulated to convert it to the actual physical address. The conversion software determines this by using the physical address of the beginning of the file, the length of each record in the file, and the relative address of the record being sought.
A logical key pointer contains the primary key of the related record. This key value is then converted into the record's physical address by a hashing algorithm.
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