Data Structure (2130702)

BE | Semester-3   Winter-2017 | 11/14/2017

Q4) (a)

Explain indexing structure for index files.

Indexing

  • Indexing is used to speed up retrieval of records.
  • It is done with the help of a separate sequential file. Each record of in the index file consists of two fields, a key field and a pointer into the main file.
  • To find a specific record for the given key value, index is searched for the given key value.
  • Binary search can used to search in index file. After getting the address of record from index file, the record in main file can easily be retrieved.
  • Index file is ordered on the ordering key Roll No. each record of index file points to the corresponding record. Main file is not sorted.
Indexing