Abstract: “Generally, the query optimizer cannot be accessed directly by users: once queries are submitted to database, and parsed by the parser, they are then passed to the query optimizer where optimization occurs. Each different way typically requires different processing time. The purpose of query optimization, which is an automated process, is to find the way to process a given query in minimum time. According to the basic operation of query such as scanning, aggregation, join. we present a four type of query a cross different size of tables to explain query performing through execution time to improve query execution time during optimization”

Keywords: Query optimization, Query execution time, SQL server 2012 technologies