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1.
浅议关系型数据库的查询优化问题   总被引:1,自引:0,他引:1  
随着关系型数据库中数据的增加。系统的响应速度逐渐成为一个亟待解决的主要问题。SQL语句是数据库应用中一个非常关键的部分.其执行性能的高低直接影响着应用系统的运行效率。因此.系统优化中一个很重要的方面就是对SQL语句的优化。在数据库应用程序的编写中,通过对SQL语句实施优化、合理安排关系操作的顺序.可以节省时间和空间,提高查询效率。  相似文献   

2.
SQL语句的查询优化分析   总被引:4,自引:0,他引:4  
随着关系型数据库中数据的增加,系统的响应速度便成为需要解决的主要问题之一。SQL语句是数据库应用中一个非常关键的部分,其执行性能的高低直接影响着应用系统的运行效率。因此,系统优化中一个很重要的方面就是对SQL语句的优化。在数据库应用程序的编写中,通过对SQL语句  相似文献   

3.
多进程在银行联机事务批量处理中的应用   总被引:1,自引:0,他引:1  
随着计算机在银行业中的深入应用,许多银行业务,尤其核心业务的开展都以数据库为依托。数据库技术与银行业发展的联系越来越密切。目前大多数银行采用C/S系统架构,后端数据库服务器响应前端发起的各种交易,前端交易的信息最终以数据形式中存放在后台数据库中。后台数据库服务器是银行日常联机交易的核心,其稳定可靠的运行、迅速的响应速度、较高的吞吐量以及24小时不间断运行,是为客户提供优质服务的前提,是银行业务正常发展的保证,也是提高自身竞争力的基础。由于业务需要,经常要对数据库关键表进行全表更新处理,如银行年度结息、批量扣收卡年费等,还要在效率、可靠性、并发及硬件资源之间权衡。在保证可靠性的前提下,充分利用硬件资源,尽可能不影响其他业务的正常运行,即最大化并发、高效率地完成更新操作。这就需要软件开发人员熟悉银行业务,充分应用数据库技术及编程技巧,开发出优质高效的应用软件,保证业务稳定持续发展。  相似文献   

4.
Sybase数据库在我国金融系统中应用十分广泛。由于其应用程序每天对数据库进行大量的插入更新、删除等操作,在数据库的物理存储介质上产生了大量存储碎片,从而影响了存储的效率以及数据库应用运行的速度。下面笔者将简要介绍一种Sybase数据库碎片的整理方法。  相似文献   

5.
通过对SYBASE数据库系统的内存管理机制进行分析,讨论了在应用系统中如何充分有效地使用和管理内存,以提高系统的运行效率。  相似文献   

6.
PowerBuilder 是美国 Powersoft 公司推出的基于客户/服务器结构图型界面数据库开发软件。它可以操纵众多大型数据库和桌面数据库,支持多种硬件平台。PowerBuilder 的主要应用基于数据库,如何在 PowerBuilder 程序设计中,高效地进行数据统计、查询、打印等工作,是程序设计者面临的重要技术难点。下面,笔者具体介绍几则报表设计技巧。  相似文献   

7.
目前,informix数据库管理系统被广泛用于金融、保险、证券、电信等行业的营业主机系统,许多柜台的营业系统也大量使用Informix数据库系统。因此,Informix数据库的性能及使用效率高低直接影响到各种业务的正常运行与发展。那么,如何保证Informix数据库的高性能及高效率呢?定期对数  相似文献   

8.
付欣 《中国外资》2013,(24):287-287
计算思维是新时期一种全新的教育理念,目前已经成为各界关注的重点。同时在高校计算机程序设计教学中计算思维的培养和应用,也是新时期计算机基础教学的目标之一。本研究首先介绍了计算思维,然后详细分析了计算思维在计算机数据库程序设计课程中的应用,以提高学生的程序设计能力和思维能力。  相似文献   

9.
建设银行河北省分行城市综合业务网是一个以城市为单位建立数据中心并通过广域网实现城市间互联的大型网络系统,其硬件平台主要为IBMRS/6000、HP9000系列开放式企业级服务器,数据库平台为Informix,应用开发工具为ESQL/C。本文结合工作实践及模拟业务系统压力测试情况,介绍一下如何提高Informix数据库的运行效率。一、定期执行数据库的UpdateStatistics功能为了提高数据库的效率,Informix提供了一个基于成本的查询优化器。执行UpdateStatistics就是将创建数据库表的有关统计信息更新到数据库系统的Sysmaster库中,以便查询优…  相似文献   

10.
提高高校程序设计课程的教学效率,最大限度的培养学生的思维方式和应用能力以提高学生的综合素质是实际教学过程中急需解决的问题。  相似文献   

11.
I.F. Clarke 《Futures》1985,17(2):170-184
With this survey of developments in the futures field since 1945, I.F. Clarke completes his present series for Futures. He makes two major points: that forecasting techniques have become essential tools in the management of change; and that nuclear weapons and ecological problems have added a moral dimension to the study of the future. In the next issue of Futures he will start a new series on the range of future-thinking in the USA, from the expectations of the first settlers to the Star Wars programme.  相似文献   

12.
融资融券业务正式运营已经开展,为证券市场带来了革命性的改革,作为证券市场的一大主体,基金公司面对融资融券也迎来了新的发展方向和挑战,本文从融资融券业务的运行机制入手,分析了基金公司融资融券的新契机,并对其即将面临的问题进行审视和剖析,进而提出策略建议.  相似文献   

13.
银监会分设后,人民银行将专司货币政策、金融稳定、金融服务三大职能。作为人民银行的分支机构,基层人民银行的工作重心也将从金融监管调整到这三大职能上来。人民银行的科技部门,就要积极运用科技手段,为人民银行履行新的职能发挥“服务、支持、促进、发展”的作用。一、围绕三大职能搭建五大平台经过“六五打基础、七五作准备、八五大发展”几个阶段后,人民银行相继实现了核算电算化、清算网络化和办公信息化。特别是近一两年来,陆续开通了大额支付系统、信贷登记咨询系统、会计四集中系统、金融信息服务网站等系统,人民银行信息化水平又…  相似文献   

14.
Abstract:  Prior research has shown the prevalence of measurement error in models used to estimate aggregate discretionary accruals. In these models, the incremental information content of the various components of accruals is ignored. Limited prior research and data gathered from firms under Securities and Exchange Commission (SEC) litigation indicate that managers use either one or more than one component of accruals simultaneously, in a consistent way to manipulate bottom-line earnings in a given direction. I propose two measures that capture the consistency between the discretionary components of accruals and test their significance in earnings management (EM) detection in firms that have artificially added accrual manipulation and firms that were targeted by the SEC for accrual manipulation. There is evidence that this information is incrementally useful in detecting EM. This finding paves the way for improvements in the discretionary accruals measure by including consistency information from the components of aggregate accruals.  相似文献   

15.
在中国,所有制形式的调整、改革与完善,先进生产力的发展,党的执政能力建设,是社会主义建设过程中密切结合在一起的三个不同层面的发展关系.应在相互促进和共同提高中促进社会的和谐发展,保证社会主义现代化建设战略目标的顺利实现.  相似文献   

16.
Abstract

The Society of Actuaries undertook a three-phase research project on mortality improvement in the three NAFTA countries: Canada, Mexico, and the U.S. Phase 1 consisted of a literature review of papers on projecting mortality levels in the future and a study of the trend in mortality improvement during this century. Phase 2 consisted of a discussion of different facets of modeling mortality rates at a seminar attended by 79 experts (actuaries, demographers, economists, and medical researchers) representing different countries. The last session of the seminar consisted of the completion of a survey by the attendees to obtain input for Phase 3, which would analyze the impact of mortality improvement on the social security system of each country. This paper summarizes the results of the survey.

The survey results illustrate the difficulty in forecasting mortality levels, because the effects of many factors that could have significant impact on mortality rates are unknown. This suggests the need for dynamic forecasting, which allows for the possibility of random shocks. A majority of the survey respondents believe that stochastic forecasting models, despite their complexity, have significant potential to add value. Respondents also believe that both historical data and cause-specific mortality forecasts are useful as input and also in validating forecasts of the aggregate levels of mortality. The challenge is to develop more sophisticated forecasting models to produce results that are relatively easy to interpret and to communicate these results to the desired audiences, including the public and policymakers.

The survey results suggest that the aggregate effect of lifestyle changes, medical advances, diseases, catastrophe, and physical environmental changes is an increase in life span. However, there is much uncertainty about the future. Respondents expect that beyond the year 2020 the mean annual rate of reduction in mortality for males age 65 and over will average about 0.58% for Canada, 0.76% for Mexico, and 0.67% for the U.S. The results for the female age 65 and over population are 0.64%, 0.83%, and 0.70%, respectively. The age 65 and over population is expected to see larger percentage reductions in mortality than the 0–14 and 15–64 populations. The reductions in male and female mortality will be ultimately the same, and the mortality levels in the three countries will ultimately converge, although differences may persist for decades.  相似文献   

17.
一、引言随着国民经济的不断发展,银行业务与外部企业的联系越来越密切。银行正逐步成为现代经济活动的中心,作为数据处理核心的银行业务应用也越来越大型化、越来越复杂化,因此许多银行也把软件项目逐步由原来的自主开发转变为与公司合作的方式,或直接外包开发的方式,银行本身的技术人员也逐步由开发转向项目管理。二、项目外包的分类银行项目的外包有以下几种情况:①部分子系统外包,有时由于银行的软件项目太大,单靠银行自身的开发力量基本无法在预定的时间内完成项目,只好把相对独立的部分外包;②直接购买软件公司的成熟产品,有些金融软…  相似文献   

18.
银行管理信息平台建设发展的思考   总被引:4,自引:0,他引:4  
一、目前国内银行IT发展现状及面临的问题 银行数据集中工作的完成,标志着银行的业务由电子化建设阶段转入信息化建设阶段.一方面银行数据的集中提供了丰富全面的基础数据,面对日益庞大的数据源,如何将数字转化为对银行有用的信息,并从中发现知识,为银行的经营决策提供支持,是摆在银行IT人员面前的一个亟待解决的问题.另一方面用户对银行信息的需求日益增长,如果银行没有一套完整、实用的信息管理系统,将对业务发展非常不利.南京爱立信公司倒戈花旗银行事件曾经轰动一时,其中一个重要原因就是中国本地银行不能满足爱立信全球总部对南京爱立信公司的要求:每周财务上报和每天贷款限额管理.这一事件为中国商业银行的未来发展敲响了警钟,如果不加快管理信息系统的开发,迅速提升业务管理水平,类似的事件还会接连不断地发生,并最终导致国内商业银行在同国外商业银行的竞争中全面溃败.  相似文献   

19.
The separation of a unit of account (UoA) from a medium of exchange (MoE) in the commodity–money system is investigated by considering explicitly a seller's choice of UoA in terms of either an MoE or a unit of metal weight. If the likelihood of debasement of an MoE and its rate are high enough, the price is posted in terms of a unit of metal weight rather than an MoE. Interestingly, this MoE–UoA separated equilibrium yields the flexible nominal price, whereas an MoE–UoA integrated equilibrium yields the sticky one. This implies the nominal price rigidity in the fiat‐money system where MoE and UoA are integrated.  相似文献   

20.
Empirical studies suggest that time-series regression estimates of the degrees of operating and financial leverage have a tendency to produce measures less than one. According to ex ante theory, these measures should be greater than one for firms operating above the breakeven point. There have also been suggestions that the biases in these estimates may be attributable to an underlying increase in unit sales. This work presents evidence that these counter-intuitive measures are produced by changes in the firm's operating parameters (unit price, variable cost, fixed cost and interest payments). It further suggests that attempts to control for the underlying change in unit sales substantially increase the volatility of predicted estimates.  相似文献   

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