Indexing: Indexing is a way to optimize database performance by minimizing the number of disk visits required while processing queries. It is a data structure technique for quickly locating and accessing data in a database. And indexing can be created by using few database columns, the first column is the Search key, it contains a copy of the primary key or candidate key of the table, to access the corresponding data quickly, these values are usually stored in sorted order. The second column is the Data reference or Pointer, it contains a set of Pointers that hold the address of the disk block while the particular key value can be found.