Date Added: Mar 2012
In relational database large information is maintained and organized so that user can get the desired information in predictable and reliable fashion through the query processing. Retrieving these results in timely manner is Query Optimization. Optimization is a process of choosing most efficient way to execute a SQL query. This is important step in processing of any data manipulation language because in RDBMS, as in large and complicated system performance is key issue. It's an issue that one need to deal with on an ongoing basis so performance must be built in. This paper will provide the reader general concepts of query optimization in relational database system.