Abstract

The main objective of query processor is to generate the most efficient query results. Using an apt execution plan, query minimizes cost of execution for results. The order of accessing a source table is very important during query execution. The best execution plan from possible ones is presented by Query optimizer. The paper discusses various stages of query optimization using execution plan. It gives the analysis of indexes, type of expressions & joins used in the execution plan of the query. The approach gets the estimate of the cost of query joins in a query at compile time. These estimates help in the construction of a query plan at compile time and then executed at run-time.

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