Describe a technique for direct search? Explain how data is stored within a file so which direct searching can be performed.
For a file of unordered fixed length records by using unspanned blocks and contiguous allocation, it is straight forward to access any record through its position in the file. If the file records are numbered 0,1,2,---,r-1 and the records in every block are numbered 0,1,---bfr-1; whereas bfr is the blocking factor, then ith record of the file is situated in block [(i/bfr)] and is the (I mod bfr) record in that block. Such a file is frequent known as a relative or direct file because records can simply be accessed directly through their relative positions. Accessing a record based on a search condition; thus, it facilitates the construction of access paths on the file, like as the indexes.