TheCorporateMassDataQueryOptimizer企业海量数据查询优化.PDF

Computer Science and Application 计算机科学与应用, 2013, 3, 159-164 /10.12677/csa.2013.33028 Published Online June 2013 (/journal/csa.html) The Corporate Mass Data Query Optimizer Yong Ding Yunnan Institute of Business and Technology, Kunming Email: greenvc@ Received: Jan. 19th th th , 2013; revised: Mar. 9 , 2013; accepted: Mar. 24 , 2013 Copyright © 2013 Yong Ding. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract: In an application system, data query and processing speed has become a standard to measure the success or failure of the system. Thus, in large database queries, you should pay attention to the efficiency of the data query, so as not to cause a serious waste of system resources. Based on the grammar-based query optimizer works, this paper rea- sonably establishes indexing, writes good specifications SQL statement, uses appropriate expressions or keywords, makes full use of the index, avoids full table scan and improves query efficiency. Keywords: Optimize the Query; Index; SQL Statements 企业海量数据查询优化 丁 勇 云南工商学院，昆明 Email: greenvc@ 收稿日期：2013 年 1 月 19 日；修回日期：2013 年 3 月 9 日；录用日期：2013 年 3 月 24 日 摘 要：在一个应用系统中，对数据查询及处理速度已成为衡量该系统成败的标准，所以在对大型数据库查询 时，应注意数据查询的工作效率，以免造成系统资源严重浪费。本文根据以语法为基础的查询优化器的工作原 理，合理建立索引，书写规范良好的 SQL 语句，使用合适的表达式或关键字，充分利用索引，避免全表扫描， 提高查询效率。 关键词：优化查询；索引；SQL 语句 1. 引言 询时间降为