摘要
随着数据库应用系统中数据的增加,系统的性能提高成为数据库系统中需要解决的主要问题,在系统硬件不变的情况下,SQL语句的优化成为系统性能提高的主要途径。本文通过分析Oracle数据库执行SQL语句的过程,采用比较SQL语句优化之前和优化之后的执行时间和调用的数据块数量方法来判断优化效果,最后得到消耗时间少和调用数据块少的SQL语句。
In database application systems,performance becomes one of their main problems needed to be resolved with the increase of data in it.The optimization of SQL sentence is a main way to promote the performance of the system under the same hardware condition.This paper analyzes the execution processes of SQL sentence in Oracle database,compares the execution time and number of data blocks called in before and after of optimization to determine the optimal effect.Finally,the paper gets the SQL statement that time consuming less and data block calling less.
出处
《计算机与现代化》
2011年第3期124-126,130,共4页
Computer and Modernization
