Hence, the need for statistical views arises in query plan optimization. 因此,在进行查询计划优化时,就需要使用统计视图。
For statistical view, the ENABLE QUERY OPTIMIZATION clause will cause the view, and its associated statistics to be used to improve the query optimization. 对于统计视图,ENABLEQUERYOPTIMIZATION子句将导致该视图以及与之相关联的统计信息被用于改进查询优化。
The statistical view is kind of like the Materialized Query Table ( MQT), except that there is no need for materialization. 统计视图有点类似于物化查询表(MaterializedQueryTable,MQT),不同的是统计视图不需要物化。
Both statistical views and REOPT allow the optimizer to compute a more accurate cardinality estimate and consequently choose an optimal query execution plan. 统计视图和REOPT都使优化器可以计算出更精确的基数估计,而后选择一个最佳查询执行计划。
Using the same sample data just discussed above, the following illustrates the difference in cardinality estimates with and without the use of statistical view for the query. 下面使用以上讨论的相同的示例数据,阐释在使用和不使用查询的统计视图的情况下基数估计的差别。
So, the accuracy of getting an optimal plan is entirely dependant on the up-to-date statistical information about the database objects involved in the query. 因此,获得最佳计划的准确性完全取决于关于查询中所涉及的数据库对象的最新统计信息。
These views include columns containing statistical information that is useful to the query optimizer. 这些视图包括一些包含对查询优化器有用的统计信息的列。
This may mean pushing down joins between tables on the same data source, automatically using probe type lookups where appropriate, and using the most efficient join technique based upon indexes and statistical information available at the time the query is executed. 这意味着下推相同数据源上的表之间的连接,在适用的情况下自动使用探测类型查找,在查询执行时,根据已有的索引和统计信息使用最有效的连接技术。
Statistical profiles are then generated based on the data in the query feedback warehouse. 然后,基于查询反馈仓库中的数据生成统计配置文件。
For the requirement of hierarchical statistics reports creation, a dynamic reports scheme based on XML and Cell control is put forward. The scheme realizes the separation of reports description and program code, and can response to the changes of statistical hierarchy and query conditions. 针对层次可变的报表应用需求,提出一种基于XML描述和Cell组件的动态报表开发方案,可实现报表描述和代码的分离,能及时响应管理层次的变化和用户查询条件的改变。
The MS algebra extends the relational algebra with extended operation semantics, the extended set of operation objects and new algebraic operators that support the statistical analysis queries. MS algebra is a theoretical framework for statistical and scientific database query languages. 二是MS代数包括很多支持统计分析查询的新代数操作,MS代数是构造对用户友好的统计与科学数据库查询语言的理论基础。
Methods: The distributed data base system was composed of three software which were patients satisfactory scale, evaluation software in hospital and statistical query module and values in the system were assigned according to the managing oriented theory and the statistical demand. 方法:采用分布式数据库,由住院病人满意度评分软件、院内评分软件及统计查询模块三部分组成。
A Statistical Query Expansion Model Based on Query Logs 基于用户日志的查询扩展统计模型
Center workstation tests and controls field equipments, dynamically display technical process, field data and alarm, production information for statistical query. 中心工作站检测和控制现场设备,动态显示工艺流程和现场数据并报警,统计查询生产信息等。
The system includes functions such as sign in/ sign out, absence monitoring, real time statistical query, result output and system maintenance. 本系统主要包括签到、离岗画面、实时统计查询、员工考勤表打印和系统维护等功能。
Statistical Query Expansion Model Based on Average Mutual Information 基于上下文平均互信息的问句查询扩展模型
By entering the name, unit code, biographical information and other basic information, the system generates the appropriates statistical data and various statistical reports for users to query and print. In addition administrators can also update and delete the basic information regularly. 用户通过输入姓名、单位代码、履历等基本信息,由系统自行生成相应的统计数据及各类统计报表以供用户查询、打印,另外管理员还可以对这些基本信息进行定期的更新和删除。
It provides rich statistical statement, convenient updating various base information, management security, query convenient, easy to operate etc characteristics. 此外系统还具有提供丰富的统计报表、方便地修改各种基本信息、管理安全、查询方便、操作简便易学等特点。
Abstract: In this article, production, distribution and utilization will be researched in detail by various statistical investigation methods including random sampling research, major surveys and typical investigation, information query, questionnaire paid for money. 本文采用随机抽样调查、重点调查和典型调查及资料查询、有偿问卷调查等多种统计调查方法,对河南复混肥料生产、流通、利用3个方面开展研究。
Combining the statistical summary information and semantic caching, the service improves the performance of semantic caching, and greatly enhances the capacity of system query ability. 该服务通过统计将统计的摘要信息和语义缓存相结合,实现了语义缓存维护性能的提高,使系统整体查询性能得到大幅提升。
The Civil Aviation in major information systems currently accumulated a lot of historical operating data, but many remain in traditional relational database approach to the statistical reports, etc., only for data query, statistical and other functions. 虽然民航目前在各大信息系统积累了大量的历史运行数据,但许多系统仍然以传统的关系数据库中的统计报表等方式进行,只是实现数据的查询、统计等功能。
The topology display, fault management, statistical indicators, data query and analysis functions are realized. 实现了拓扑显示、故障管理、指标统计、数据查询与分析等功能。
The system implement the functional design of five modules of the scientific and educational management system of University of Chinese medicine affiliated hospital, personnel management, department management, statistical query management, credit points management and system setting management. 本系统实现了中医药大学附属医院科教管理系统中的人员管理、科室管理、统计查询功能、学分管理以及系统设置功能五大功能的设计。
The functions and contents of the system are as follows: ( 1) Statistical analysis and query. 系统具体功能和内容主要包括:(1)统计分析和查询。
This system consists of base management, tracing management and statistical management. It improves the information utilization rate and supervision effectiveness by GPS, online supervision, online query and data sharing. 该系统由基地管理、追溯管理、统计管理等几个部分组成,通过基地GPS定位、在线监管、网络在线查询、数据信息共享,提高了信息的利用率,提高了工作效率和监管有效性。
System has set up three major importers which are administrators, graduates and business, according to the type of user, the system provide the functions of graduate information collection, education certificate management, statistical analysis, information query and information dissemination. 系统设置了管理员、毕业生、企业单位三大入口,根据用户类型,提供毕业生信息采集、学历证书管理、统计分析、信息查询和信息发布等功能。
The system automatically on the entry of the military vehicle quality information for statistical analysis, generate various reports and graphics, and can light to the query. 该系统自动对录入的车辆质量信息进行统计分析,生成各种报表和图形,并能轻便地实现查询。
All statistical analysis of query speed remains less than 1 second response time. 所有统计分析查询速度依然保持在1秒以下的响应速度。
For the application of low-rent tenants in the management of low-rent housing security, audit, occupancy and management workflow automation management, and low-cost households in the queue and the statistical query functions. 针对廉租住房保障管理中廉租住户的申请、审核、入住等管理工作流程实现了自动化的管理,并实现了廉租户依次轮候和统计查询功能。