An analysis of execution plans in query optimization

A major task of query processor is to produce query results, as efficiently as possible. For efficient query result, query has to follow proper execution plan which minimizes the cost of query execution. The sequence in which source tables are accessed during query execution is very important. Query optimizer which is the core component of query processor gives the best execution plan from many possible plans for the same query. The paper is the extended version of previous work [12]. Paper describes four phases of query optimization along with their execution plan. It gives the analysis of access methods and different types of joins used in execution plan of the query.