摘 要 介绍了抽奖信息管理系统的设计思路和基本原理,结合Access,通过软件系统开发,实现了具有随机性和相对均衡性的抽奖。 关键词 抽奖系统 Access VBA 随机 相对均衡性 引言 当今社会,各种各样的抽奖活动相当普遍,抽奖活动的基本原则和主要特征是随机性
摘 要 介绍了抽奖信息管理系统的设计思路和基本原理,结合Access,通过软件系统开发,实现了具有随机性和相对均衡性的抽奖。
关键词 抽奖系统 Access VBA 随机 相对均衡性
引言
当今社会,各种各样的抽奖活动相当普遍,抽奖活动的基本原则和主要特征是随机性,但对于某一团体内部的抽奖活动来说,还有一个相对均衡的问题,所谓相对均衡就是指让各个部门的中奖概率和其人数占总人数的比重大致相等。基于Access,结合其内置VBA语言,通过程序设计实现抽奖的随机,通过算法研究实现抽奖的相对均衡。本文主要介绍了系统原理以及主要程序的设计。
系统组成及原理
抽奖系统主要由来宾登记、奖票管理、幸运抽奖、获奖查询四个基本模块构成,登记模块登记参加抽奖人员,奖票管理模块初始化参加抽奖人员名单,抽奖模块实现抽奖功能,获奖查询模块查询获奖结果。其中,抽奖模块中可以实现奖励等级、总抽奖数、每一次抽奖数的控制。系统架构框图如图1。
图1 系统架构
系统初始化
来宾登记模块中已经收录了参加抽奖的人员名单以及所属部门,在奖票管理模块中,当点击初始化按钮时通过内部程序设计首先把上次的抽奖结果清空,同时利用 Rnd在参加抽奖的人员名单前随机生成一系列的序号,为幸运抽奖模块中的随机抽奖做准备[1]。主要初始化程序代码如下:
DoCmd.SetWarnings False
DoCmd.OpenQuery "删除对奖票号", acNormal, acEdit
DoCmd.OpenQuery "追加对奖票号", acNormal, acEdit
DoCmd.SetWarnings True
Set qrs = CurrentDb.OpenRecordset("对奖票号")
qrs.MoveFirst
i = 1
Do While Not qrs.EOF
qrs.Edit
qrs!序号 = Int((211 - 1) * Rnd)
qrs!对奖号码 = i
qrs.Update
i = i + 1
qrs.MoveNext
Loop
MsgBox ("对奖名单初始化完毕。")
qrs.Close
抽奖功能的实现
通过抽奖模块实现最终抽奖功能。
通过奖励等级组合框控制抽奖等级,通过抽奖数量组合框控制每批次抽奖数量,通过总抽奖数组合框控制总抽奖数。当奖励等级分别为一、二、三等奖时,抽奖数量和总抽奖数默认值分别
为5、10、10和10、30、50。各组合框的具体数值也可以通过上下箭头控制。抽奖界面如图2。
图 2 抽 奖 界 面
其程序设计比较简单,主要程序如下:
……
If Me!奖励等级.Value = 1 Then
Me!总数量.Value = 10
End If
If Me!奖励等级.Value = 2 Then
Me!总数量.Value = 30
End If
If Me!奖励等级.Value = 3 Then
Me!总数量.Value = 50
End If
Forms!抽奖.Q_抽奖统计.Requery
If Me!奖励等级.Value = 1 Then
Me!抽奖数量.Value = 5
End If
If Me!奖励等级.Value = 2 Or Me!奖励等级.Value = 3 Then
Me!抽奖数量.Value = 10
End If
……
通过点击开始按钮开始抽奖,同时按钮标题变为停止,再次点击停止此批次抽奖,同时按钮标题变为开始,继续点击开始下一批次抽奖,如此反复,直至完成总抽奖数,此时提示“抽奖总数已到”,如果未完成总抽奖数就开始另外一轮抽奖,则提示“抽奖限制”。
内部抽奖主要解决随机性和相对均衡两个问题。系统初始化在参加抽奖人员名单前随机生成了序号,通过查询“号码重排序”将参加抽奖人员名单按照序号升序排列,抽奖时按照序号顺序抽奖,实现了随机的要求。相对均衡要求大致按照各个部门人数占总人数的百分比来分配中奖人数,本系统采用各个部门占总人数的百分比乘以抽奖总数的方法来大致确定各个部门的中奖人数,有小数的数字通过程序设计进行四舍五入处理。需要注意的是,若使所有的部门中奖人数都要用四舍五入的方法进行处理则可能出现错误,为了避免这种情况需要选定一个部门,,使其中奖人数等于总抽奖数减去其他各个部门中奖人数之和[2]。抽奖模块的主要程序代码如下:
……
N = 0
cnt = Me!电科.Value + Me!电气.Value + Me!自动化.Value + Me!通信.Value + Me!院办.Value + Me!退休.Value
Do While Me!抽奖数量.Value > N And Not qrs.EOF And cnt
'电科抽奖
’四舍五入确定电科中奖数
If Me!电科.Value
If qrs.单位 = "电科" And qrs!批次.Value = 0 Then
Me!电科.Value = Me!电科.Value + 1
qrs.Edit
qrs!奖励等级.Value = Me!奖励等级.Value
qrs!批次.Value = Me!批次.Value
qrs.Update
N = N + 1
End If
Else
End If
……
'退休抽奖
cnt = Me!电科.Value + Me!电气.Value + Me!自动化.Value + Me!通信.Value + Me!院办.Value + Me!退休.Value
cnt2= Me!电科.Value + Me!电气.Value + Me!自动化.Value + Me!通信.Value + Me!院办.Value
'剩余数量分配给退休
If Me!退休.Value
If qrs22.单位 = "退休" And qrs!批次.Value = 0 Then
Me!退休.Value = Me!退休.Value + 1
qrs.Edit
qrs22!奖励等级.Value = Me!奖励等级.Value
qrs22!批次.Value = Me!批次.Value
qrs22.Update
N = N + 1
End If
Else
End If
……
’判断是否完成抽奖
cnt = Me!电科.Value + Me!电气.Value + Me!自动化.Value + Me!通信.Value + Me!院办.Value + Me!退休.Value
If cnt = Me!总数量.Value Then
MsgBox ("抽奖总数已到。")
Me.可抽奖.Value = 0
Else
MsgBox ("抽奖限制。")
End If
……
结论
本系统利用Access数据库,结合其内置VBA语言,探讨了系统初始化、抽奖的随机性和相对均衡性等关键问题,满足了抽奖的要求。进行适当调整,该系统可以应用于多种抽奖场合。

MySQLoffersvariousstorageengines,eachsuitedfordifferentusecases:1)InnoDBisidealforapplicationsneedingACIDcomplianceandhighconcurrency,supportingtransactionsandforeignkeys.2)MyISAMisbestforread-heavyworkloads,lackingtransactionsupport.3)Memoryengineis

Common security vulnerabilities in MySQL include SQL injection, weak passwords, improper permission configuration, and unupdated software. 1. SQL injection can be prevented by using preprocessing statements. 2. Weak passwords can be avoided by forcibly using strong password strategies. 3. Improper permission configuration can be resolved through regular review and adjustment of user permissions. 4. Unupdated software can be patched by regularly checking and updating the MySQL version.

Identifying slow queries in MySQL can be achieved by enabling slow query logs and setting thresholds. 1. Enable slow query logs and set thresholds. 2. View and analyze slow query log files, and use tools such as mysqldumpslow or pt-query-digest for in-depth analysis. 3. Optimizing slow queries can be achieved through index optimization, query rewriting and avoiding the use of SELECT*.

To monitor the health and performance of MySQL servers, you should pay attention to system health, performance metrics and query execution. 1) Monitor system health: Use top, htop or SHOWGLOBALSTATUS commands to view CPU, memory, disk I/O and network activities. 2) Track performance indicators: monitor key indicators such as query number per second, average query time and cache hit rate. 3) Ensure query execution optimization: Enable slow query logs, record and optimize queries whose execution time exceeds the set threshold.

The main difference between MySQL and MariaDB is performance, functionality and license: 1. MySQL is developed by Oracle, and MariaDB is its fork. 2. MariaDB may perform better in high load environments. 3.MariaDB provides more storage engines and functions. 4.MySQL adopts a dual license, and MariaDB is completely open source. The existing infrastructure, performance requirements, functional requirements and license costs should be taken into account when choosing.

MySQL uses a GPL license. 1) The GPL license allows the free use, modification and distribution of MySQL, but the modified distribution must comply with GPL. 2) Commercial licenses can avoid public modifications and are suitable for commercial applications that require confidentiality.

The situations when choosing InnoDB instead of MyISAM include: 1) transaction support, 2) high concurrency environment, 3) high data consistency; conversely, the situation when choosing MyISAM includes: 1) mainly read operations, 2) no transaction support is required. InnoDB is suitable for applications that require high data consistency and transaction processing, such as e-commerce platforms, while MyISAM is suitable for read-intensive and transaction-free applications such as blog systems.

In MySQL, the function of foreign keys is to establish the relationship between tables and ensure the consistency and integrity of the data. Foreign keys maintain the effectiveness of data through reference integrity checks and cascading operations. Pay attention to performance optimization and avoid common errors when using them.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Dreamweaver Mac version
Visual web development tools
