数据库系统概念原书第5版(英文)第九章ppt
合集下载
数据库系统基本概念课件
第三方监控工具
如New Relic、Dynatrace等，提供更全面、灵活的数据库性能监控和报警功能 ，支持多种数据库平台。
THANKS
感谢观看
数据库系统基本概念课件
• 数据库系统概述 • 数据模型与数据结构 • 数据库设计与管理 • 查询语言与优化技术 • 数据库事务处理与并发控制 • 备份恢复与性能监控
01
数据库系统概述
定义与发展历程
数据库定义
数据库是一个长期存储在计算机 内、有组织的、可共享的、统一 管理的大量数据的集合。
发展历程
数据独立性
数据和程序相互独立，数据的 逻辑结构和物理结构的变化不 影响应用程序。
安全性与完整性
数据库系统提供了数据的安全 性控制和完整性约束，保证了
数据的正确性和可靠性。
应用领域及现状
应用领域
广泛应用于金融、制造、物流、医疗、教育、科研等各个领域，成为信息化社 会的重要基础设施。
现状
随着大数据、云计算、人工智能等技术的快速发展，数据库系统面临着新的挑 战和机遇，如分布式数据库、云数据库、时序数据库等新型数据库不断涌现。
访问控制
通过设置用户角色和权限 ，限制用户对数据库的访 问和操作，防止未经授权 的访问和数据篡改。
数据备份与恢复
定期对数据库进行备份， 确保在数据丢失或损坏时 能够恢复数据，保障业务 的正常运行。
04
查询语言与优化技术
SQL查询语言基础
SQL概述
介绍SQL语言的发展、特点及应用领域。
数据查询语言（DQL）
经历了人工管理、文件系统、数 据库系统三个阶段，目前正向大 数据、云计算、人工智能等方向 发展。
数据库系统特点与优势
数据结构化
如New Relic、Dynatrace等，提供更全面、灵活的数据库性能监控和报警功能 ，支持多种数据库平台。
THANKS
感谢观看
数据库系统基本概念课件
• 数据库系统概述 • 数据模型与数据结构 • 数据库设计与管理 • 查询语言与优化技术 • 数据库事务处理与并发控制 • 备份恢复与性能监控
01
数据库系统概述
定义与发展历程
数据库定义
数据库是一个长期存储在计算机 内、有组织的、可共享的、统一 管理的大量数据的集合。
发展历程
数据独立性
数据和程序相互独立，数据的 逻辑结构和物理结构的变化不 影响应用程序。
安全性与完整性
数据库系统提供了数据的安全 性控制和完整性约束，保证了
数据的正确性和可靠性。
应用领域及现状
应用领域
广泛应用于金融、制造、物流、医疗、教育、科研等各个领域，成为信息化社 会的重要基础设施。
现状
随着大数据、云计算、人工智能等技术的快速发展，数据库系统面临着新的挑 战和机遇，如分布式数据库、云数据库、时序数据库等新型数据库不断涌现。
访问控制
通过设置用户角色和权限 ，限制用户对数据库的访 问和操作，防止未经授权 的访问和数据篡改。
数据备份与恢复
定期对数据库进行备份， 确保在数据丢失或损坏时 能够恢复数据，保障业务 的正常运行。
04
查询语言与优化技术
SQL查询语言基础
SQL概述
介绍SQL语言的发展、特点及应用领域。
数据查询语言（DQL）
经历了人工管理、文件系统、数 据库系统三个阶段，目前正向大 数据、云计算、人工智能等方向 发展。
数据库系统特点与优势
数据结构化
《数据库系统概念教学课件》ch
安全控制措施
为了确保数据库系统的安全性，应采取一系列安全控制措施，如用户身份验证、访问控制、数据加密、审计跟踪等。这些措施有助于防止未经授权的访问和数据篡改，保护数据的机密性和完整性。
பைடு நூலகம்
数据库系统的安全性
数据库系统的维护与管理
数据库维护的目的：数据库维护的目的是确保数据库系统的性能、可靠性和安全性。通过定期的维护和管理，可以及时发现和解决潜在的问题，保持数据库系统的正常运行。
用户信息管理
数据库系统存储用户注册信息、购物记录和行为数据，帮助电子商务平台进行个性化推荐和营销策略制定。
数据库系统在电子商务中的应用
案例一
某电商平台的数据库系统架构，如何应对高并发访问和大数据量存储的挑战。
案例二
某银行的核心业务系统，如何通过数据库系统实现金融交易的安全和高效。
案例三
某社交平台的用户关系管理，如何利用数据库系统进行用户关系分析和社交网络构建。
数据库系统的实际案例分析
03
02
01
04
数据库系统的安全性与维护
数据库系统安全性的重要性
随着信息技术的快速发展，数据库系统已成为企业和组织的重要资产。保护数据库系统的安全性对于防止数据泄露、非法访问和恶意攻击至关重要。
常见的数据库安全威胁
包括未经授权的访问、数据篡改、非授权的数据泄露以及拒绝服务等。这些威胁可能来自内部人员、外部黑客或恶意软件。
查询操作
插入操作
更新操作
01
02
04
03
通过UPDATE语句修改数据库中的数据。
介绍SQL语言的基本语法和功能。
通过INSERT语句向数据库中插入新数据。
数据库系统查询语言
为了确保数据库系统的安全性，应采取一系列安全控制措施，如用户身份验证、访问控制、数据加密、审计跟踪等。这些措施有助于防止未经授权的访问和数据篡改，保护数据的机密性和完整性。
பைடு நூலகம்
数据库系统的安全性
数据库系统的维护与管理
数据库维护的目的：数据库维护的目的是确保数据库系统的性能、可靠性和安全性。通过定期的维护和管理，可以及时发现和解决潜在的问题，保持数据库系统的正常运行。
用户信息管理
数据库系统存储用户注册信息、购物记录和行为数据，帮助电子商务平台进行个性化推荐和营销策略制定。
数据库系统在电子商务中的应用
案例一
某电商平台的数据库系统架构，如何应对高并发访问和大数据量存储的挑战。
案例二
某银行的核心业务系统，如何通过数据库系统实现金融交易的安全和高效。
案例三
某社交平台的用户关系管理，如何利用数据库系统进行用户关系分析和社交网络构建。
数据库系统的实际案例分析
03
02
01
04
数据库系统的安全性与维护
数据库系统安全性的重要性
随着信息技术的快速发展，数据库系统已成为企业和组织的重要资产。保护数据库系统的安全性对于防止数据泄露、非法访问和恶意攻击至关重要。
常见的数据库安全威胁
包括未经授权的访问、数据篡改、非授权的数据泄露以及拒绝服务等。这些威胁可能来自内部人员、外部黑客或恶意软件。
查询操作
插入操作
更新操作
01
02
04
03
通过UPDATE语句修改数据库中的数据。
介绍SQL语言的基本语法和功能。
通过INSERT语句向数据库中插入新数据。
数据库系统查询语言
数据库系统概念PPT第一章,对应原版教材第五版
Instance – the actual content of the database at a particular point in time
Analogous to the value of a variable
Physical Data Independence – the ability to modify the physical schema
Security problems
Database systems offer solutions to all the above problems
Database System Concepts
1.5
©Silberschatz, Korth and Sudarshan, Bo Zhou
Data Abstraction
1.6
©Silberschatz, Korth and Sudarshan, Bo Zhou
Levels of Abstraction
A major purpose of database system is to provide an abstract of
view of data, and hide the certain detail of data storage.
Integrity constraints (e.g. account balance > 0) become part
of program code
Hard to add new constraints or change existing ones
Database System Concepts
without changing the logical schema
Analogous to the value of a variable
Physical Data Independence – the ability to modify the physical schema
Security problems
Database systems offer solutions to all the above problems
Database System Concepts
1.5
©Silberschatz, Korth and Sudarshan, Bo Zhou
Data Abstraction
1.6
©Silberschatz, Korth and Sudarshan, Bo Zhou
Levels of Abstraction
A major purpose of database system is to provide an abstract of
view of data, and hide the certain detail of data storage.
Integrity constraints (e.g. account balance > 0) become part
of program code
Hard to add new constraints or change existing ones
Database System Concepts
without changing the logical schema
数据库管理系统PPT课件
数据库索引文件:.DCX 报表文件: .FRX
表单文件: .SCX
程序文件: .PRF
项目文件: .PJX 内存变量文件:.MEN
主要性能指标
每个数据表最多的记录数:10亿条 每条记录的最大长度:64K字节 每条记录的最多字段数:255个. 字符型字段的最多字符数:255个 数值精度:16位 命令行的最多字符数:8192个 最大数组数:65000 最多可设置的内存变量:65000
向导概念： 向导是交互式的程序，能帮助您快速完成一般性
的任务 向导使用方法：
1、启动 2、定位向导屏幕 3、保存向导结ห้องสมุดไป่ตู้ 4、修改向导创建的项
第五章 创建数据库
设计数据库 创建一个数据库 创建表和索引 数据库的操作
一、设计数据库
确定建立数据库的目的 确定需要的表 确定所需的字段 确定关系 设计求精，对设计进一步分析，查找其中的
四、中文VFP6.0的安装、运行和退出
中文VFP6.0的安装和启动 集成工作环境：
主窗口、驻菜单栏、工具栏、命令窗口和状态栏 中文VFP6.0的操作方式
1、交互命令方式（命令窗口） 2、菜单操作方式 3、程序执行方式
五、项目管理器的使用
项目管理器： 项目管理器是中文VFP6.0中处理数据和对象的主要组织工
数据库操作 a、查看和修改数据库结构 b、查看数据库分层结构
modify database testdata c、管理数据库 删除数据库：delete database 选择当前数据库中的表：use ? 关闭数据库：close datebase
第四章 数据库系统的概念
一、有关数据库的概念 数据库
有关联的数据有组织地、合理地存放在计算机上的集合。 数据库管理系统
数据库系统概念(第五版)Abraham Silberschatz著,CH10
Database System Concepts - 5th Edition, Aug 22, 2005.
10.2
©Silberschatz, Korth and Sudarshan
Introduction
XML: Extensible Markup Language Defined by the WWW Consortium (W3C) Derived from SGML (Standard Generalized Markup Language), but simpler to use than SGML Documents have tags giving extra information about sections of the document E.g. <title> XML </title> <slide> Introduction …</slide> Extensible, unlike HTML Users can add new tags, and separately specify how the tag should be handled for display
Chapter 10: XML
Database System Concepts
©Silberschatz, Korth and Sudarshan See for conditions on re-use
XML
Structure of XML Data XML Document Schema Querying and Transformation Application Program Interfaces to XML Storage of XML Data XML Applications
数据库英文课件9
5
Schemas（模式）
The name of a relation and the set of attributes for a relation is called the schema for that relation. We show the schema for the relation with the relation name followed by a parenthesized list of its attributes.
25
Exercise
Required: Convert the E-R diagram you designed in last exercise into a relational database schema.
26
3.5 Functional Dependencies
Definition of Functional Dependency(函数依赖)
Example: Movies (title, year, length, fileType)
Database schema = a set of all relation schemas
Movies(Title, Year, Length, FileType) Star(Name, Age) Studio(StudioName, Addr)
参照完整性
例３：学生（学号，姓名，性别，专业号，年龄，班长） 定义：外码
外码
设F是参照关系R的一个或一组属性，但不是R的码， 若F与被参照关系S的主码相对应，则称F是R的外码（
详细定义见教材P54）
规则：参照关系R中每个元组在外码F上的值必须 为：
数据库系统概念原书第5版(英文)第一章ppt
Database designers: design database ―schema‖ to model aspects of the real world Database application developers: build applications that interface with databases Database administrators (a.k.a. DBA‘s): load, back up, and restore data, fine-tune databases for performance DBMS implementors: develop the DBMS or specialized data management software, implement new techniques for query processing and optimization inside DBMS
August 15, 2013
Dept. of Comp. Sci. & Tech., Tongji Uni.
4
What is a database?
A very large, integrated collection of data
The amount of data is very large The data is structured and interrelated The data is integrated Entities (e.g., students, courses) Relationships (e.g., Li is taking Database and Knowledge) More recently, also includes active components (e.g. “business logic”)
August 15, 2013
Dept. of Comp. Sci. & Tech., Tongji Uni.
4
What is a database?
A very large, integrated collection of data
The amount of data is very large The data is structured and interrelated The data is integrated Entities (e.g., students, courses) Relationships (e.g., Li is taking Database and Knowledge) More recently, also includes active components (e.g. “business logic”)
数据库系统概念原书第5版(英文)第一章PPT课件
9/29/2020
Dept. of Comp. Sci. & Tech., Tongji Uni.
4
What is a database?
A very large, integrated collection of data
The amount of data is very large The data is structured and interrelated The data is integrated
9/29/2020
Dept. of Comp. Sci. & Tech., Tongji Uni.
2
Outline of the Course (2)
Part 4 Data Storage & Querying
Chapter 11: Storage and Chapter 12: Indexing and Hashing Chapter 13: Query Processing Chapter 14: Query Optimization
recommendations Manufacturing: production, inventory,
orders, supply chain Human resources: employee records,
salaries, tax deductions
9/29/2020
Dept. of Comp. Sci. & Tech., Tongji Uni.
6
Database Management System (DBMS)
A Database Management System (DBMS) is
a software package designed to store and manage databases
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
Dept. of Comp. Sci. & Tech., Tongji Uni. 2
2013-8-15
Outline of the Course (2)
Part
Chapter 13: Query Processing
Chapter 11: Storage and File Structure Chapter 12: Indexing and Hashing Chapter 14: Query Optimization
2013-8-15
Basic Steps in Query Processing: Optimization A relational algebra expression may have many equivalent expressions Each relational algebra operation can be evaluated using one of several different algorithms Annotated expression specifying detailed evaluation strategy is called an evaluationplan
For simplicity we just use the number of block transfers from disk and the number of seeks as the cost measures
tT – time to transfer one block tS – time for one seek
4 Data Storage & Querying
Part 5 Transaction Management
Part 9 Case Studies: PostgreSQL, Oracle, IBM DB2, Microsoft SQL Server…… Other Topics: XML, Distributed Databases, Advanced topics……
cost = (br /2) block transfers + 1 seek selection condition or ordering of records in the file, or availability of indices
Dept. of Comp. Sci. & Tech., Tongji Uni. 14
Algorithm A1 (linear search).
Cost estimate = br block transfers + 1 seek
br denotes number of blocks containing records from relation r
If selection is on a key attribute, can stop on finding record(average)
disk accesses, CPU, or even network communication
Typically disk access is the predominant cost, and is also relatively easy to estimate. Measured by taking into account
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
11
Measures of Query Cost (Cont.)
Costs depends on the size of the buffer in main memory
Having more memory reduces need for disk access
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
12
Selection
Selection Operation
File scan – search algorithms that locate and retrieve records that fulfill a selection condition
Dept. of Comp. Sci. & Tech., Tongji Uni. 8
In this lecture we study
Biblioteka In next lecture
2013-8-15
Measures of Query Cost
Measures of Query Cost
Cost is generally measured as total elapsed time for answering query
Dept. of Comp. Sci. & Tech., Tongji Uni. 3
Chapter 15: Transactions Chapter 16: Concurrency Control Chapter 17: Recovery System
2013-8-15
Outline
4
Basic Steps in Query Processing
1. Parsing and translation 2. Optimization 3. Evaluation
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
5
Basic Steps in Query Processing (Cont.)
Linear search can be applied regardless of
2013-8-15
Selection Operation (Cont.)
A2 (binary search).
Applicable if selection is an equality comparison on the attribute on which file is ordered.
Number of seeks Number of blocks read
* average-seek-cost * average-block-read-cost
Number of blocks written * average-block-write-cost Cost to write a block is greater than cost to read a block
Lecture 9 Query Processing
Jihong Guan
Nov. 27, 2012 Department of Computer Science and Technology Tongji University
Outline of the Course (1)
Chapter 1: Introduction Part 1 Relational Databases Chapter 2: Relational Model (Data Model, Relational Algebra) Chapter3: SQL(Structured Query Language) Chapter 4: Advanced SQL Chapter 5: Other Relational Languages Part 2 Database Design Chapter 6: Database Design and the E-R Model Chapter 7: Relational Database Design Chapter 8: Application Design and Development
Parsing
and translation
translate
the query into its internal form. This is then translated into relational algebra. checks syntax, verifies relations
Dept. of Comp. Sci. & Tech., Tongji Uni. 7
Basic Steps: Optimization (Cont.)
Query Optimization: Amongst all equivalent evaluation plans choose the one with lowest cost
Overview
Measures of Query Cost
Selection Operation Sorting Join Operation Other Operations
Evaluation of Expressions
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
We often use worst case estimates, assuming only the minimum amount of memory needed for the operation is available
Real systems take CPU cost into account, differentiate between sequential and random I/O, and take buffer size into account We do not include cost to writing output to disk in our cost formulae
2013-8-15
Outline of the Course (2)
Part
Chapter 13: Query Processing
Chapter 11: Storage and File Structure Chapter 12: Indexing and Hashing Chapter 14: Query Optimization
2013-8-15
Basic Steps in Query Processing: Optimization A relational algebra expression may have many equivalent expressions Each relational algebra operation can be evaluated using one of several different algorithms Annotated expression specifying detailed evaluation strategy is called an evaluationplan
For simplicity we just use the number of block transfers from disk and the number of seeks as the cost measures
tT – time to transfer one block tS – time for one seek
4 Data Storage & Querying
Part 5 Transaction Management
Part 9 Case Studies: PostgreSQL, Oracle, IBM DB2, Microsoft SQL Server…… Other Topics: XML, Distributed Databases, Advanced topics……
cost = (br /2) block transfers + 1 seek selection condition or ordering of records in the file, or availability of indices
Dept. of Comp. Sci. & Tech., Tongji Uni. 14
Algorithm A1 (linear search).
Cost estimate = br block transfers + 1 seek
br denotes number of blocks containing records from relation r
If selection is on a key attribute, can stop on finding record(average)
disk accesses, CPU, or even network communication
Typically disk access is the predominant cost, and is also relatively easy to estimate. Measured by taking into account
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
11
Measures of Query Cost (Cont.)
Costs depends on the size of the buffer in main memory
Having more memory reduces need for disk access
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
12
Selection
Selection Operation
File scan – search algorithms that locate and retrieve records that fulfill a selection condition
Dept. of Comp. Sci. & Tech., Tongji Uni. 8
In this lecture we study
Biblioteka In next lecture
2013-8-15
Measures of Query Cost
Measures of Query Cost
Cost is generally measured as total elapsed time for answering query
Dept. of Comp. Sci. & Tech., Tongji Uni. 3
Chapter 15: Transactions Chapter 16: Concurrency Control Chapter 17: Recovery System
2013-8-15
Outline
4
Basic Steps in Query Processing
1. Parsing and translation 2. Optimization 3. Evaluation
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
5
Basic Steps in Query Processing (Cont.)
Linear search can be applied regardless of
2013-8-15
Selection Operation (Cont.)
A2 (binary search).
Applicable if selection is an equality comparison on the attribute on which file is ordered.
Number of seeks Number of blocks read
* average-seek-cost * average-block-read-cost
Number of blocks written * average-block-write-cost Cost to write a block is greater than cost to read a block
Lecture 9 Query Processing
Jihong Guan
Nov. 27, 2012 Department of Computer Science and Technology Tongji University
Outline of the Course (1)
Chapter 1: Introduction Part 1 Relational Databases Chapter 2: Relational Model (Data Model, Relational Algebra) Chapter3: SQL(Structured Query Language) Chapter 4: Advanced SQL Chapter 5: Other Relational Languages Part 2 Database Design Chapter 6: Database Design and the E-R Model Chapter 7: Relational Database Design Chapter 8: Application Design and Development
Parsing
and translation
translate
the query into its internal form. This is then translated into relational algebra. checks syntax, verifies relations
Dept. of Comp. Sci. & Tech., Tongji Uni. 7
Basic Steps: Optimization (Cont.)
Query Optimization: Amongst all equivalent evaluation plans choose the one with lowest cost
Overview
Measures of Query Cost
Selection Operation Sorting Join Operation Other Operations
Evaluation of Expressions
2013-8-15
Dept. of Comp. Sci. & Tech., Tongji Uni.
We often use worst case estimates, assuming only the minimum amount of memory needed for the operation is available
Real systems take CPU cost into account, differentiate between sequential and random I/O, and take buffer size into account We do not include cost to writing output to disk in our cost formulae