Bài giảng Hệ cơ sở dữ liệu - Chương 1: Giới thiệu về cơ sở dữ liệu

116 0 0
Bài giảng Hệ cơ sở dữ liệu - Chương 1: Giới thiệu về cơ sở dữ liệu

Đang tải... (xem toàn văn)

Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống

Thông tin tài liệu

Trong lĩnh vực Công Nghệ Thông Tin nói riêng, yêu cầu quan trọng nhất của người học đó chính là thực hành. Có thực hành thì người học mới có thể tự mình lĩnh hội và hiểu biết sâu sắc với lý thuyết. Với ngành mạng máy tính, nhu cầu thực hành được đặt lên hàng đầu. Tuy nhiên, trong điều kiện còn thiếu thốn về trang bị như hiện nay, người học đặc biệt là sinh viên ít có điều kiện thực hành. Đặc biệt là với các thiết bị đắt tiền như Router, Switch chuyên dụng

CHAPTER Giảng viên: Trần Thị Kim Chi 1 What is a Database What is Database Management System Introduction SQL Server SQL Server Services & Tools Introduction about SQL Server 2008 SQL Server 2008 Database - Object Questions Data and Information Data (dữ liệu) information (thơng tin) • Data is raw, unorganized facts that need to be processed Data are any facts, numbers, or text that can be processed by a computer • Information – When data is processed, organized, structured or presented in a given context so as to make it useful, it is called information DỮ LIỆU (DATA) XỬ LÝ THÔNG TIN (INFORMATION) Data and Information Data (dữ liệu) information (thông tin) Dữ liệu 10273 00298 … 151 50542 152 50075 Nguyễn Văn Hoà Nguyễn Minh Tâm CDTH7 CDTH7 20 19 Hồ Xuân Phương Lê Việt Dũng TCTH33 CNTH34 18 20 Lớp CDTH7 CDTH7 Tuổi 20 19 TCTH33 CNTH34 18 20 Thông tin: liệu ngữ cảnh STT Mã sinh viên Họ tên sinh viên 10273 Nguyễn Văn Hoà 00298 Nguyễn Minh Tâm … 151 50542 Hồ Xuân Phương 152 50075 Lê Việt Dũng   Data Model A data model is a “description” of both a container for data and a methodology for storing and retrieving data from container Data model is  Not a thing  You cannot touch it  Data model are abstractions, mathematical algorithms & Concepts What is a Database • A database a set of data that has a regular structure and that is organized in such a way that a computer can easily find the desired information Application Program Database Application Program Application Programs Users Database System Model Database management systems follow particular models (known as database models) to store and manipulate data A database model is characterized by: The way it stores data : STRUCTURE The way data in the structure are manipulated: OPERATIONS Characteristics of the Datatabase • Persistent: – Should be able to store all kinds of data that exists in this real world • Interrelated: – Data and application should be isolated – Should be able to relate the entities / tables in the database by means of a relation i.e.; any two tables should be related • Shared: – Multiple users should be able to access the same database, without affecting the other user – Database should also provide security, – Database should also support ACID property i.e.; while performing any transactions like insert, update and delete, database makes sure that the real purpose of the data is not lost Database Design  Objective  Ensuring data completeness  Avoiding data redundancies  Facilitating data access  Solution  Normalization • Reducing redundancies and improving data modification performance • Renormalizations is often done to enhance reporting performance (at the expense of disk space and redundancy)  Referential Integrity • Maintains the logical relationships between database objects Steps in Database Design  Requirement analysis What does the user want?  Conceptual database design Defining the entities and attributes, and the relationships between these The ER model  Physical database design Implementation of the conceptual design using a Database Management System 10 SQL Server 2008 Database Objects Object Names • Every object in a SQL Server 2008 database is identifiedby a four-part, fully qualified name: server.database.schema.object • Can be omitted the server name and database name • New users are assigned the default schema of dbo 102 SQL Server 2008 Database Objects Objects – – – – – – – Tables Views Stored Procedures Functions Rules Defaults Triggers 103 SQL Server 2008 Databases System Databases • The master Database: is used to record all server-level objects in SQL Server, this includes Server Logon accounts, Linked Server definitions, and EndPoints • The model Database: a template database 104 SQL Server 2008 Databases System Databases • The msdb Database: the SQL Server Agent uses the msdb database extensively for the storage of automated job definitions, job schedules, operator definitions, and alert definitions • The tempdb Database: is used extensively during SQL Server operations 105 SQL Server 2008 Databases System Databases • The resource Database: is a Read Only database that contains all system objects used by an instance of SQL Server – It contains the structure and description of all system objects 106 SQL Server 2008 Databases User Databases • Databases created by users They are created to store data used by data applications and are the primary purpose of having a database server 107 SQL Server 2008 Database Storage • Default locations for system database files associated with the first instance of SQL Server 108 SQL Server 2008 Database Storage Data Files and Filegroups • When a user database is created, it must contain at least one data file This first data file is known as the primary data file • The primary data file is a member of the default Primary filegroup • Every database has one Primary filegroup when created, which consists of at least the primary data file 109 SQL Server 2008 Database Storage Data Files and Filegroups 110 SQL Server 2008 Database Storage Log Files • Upon initial creation of a database, one transaction log must be defined • The transaction log is used to record all modifications to the database to guarantee transactional consistency and recoverability 111 SQL Server Security • SQL Server can be configured to work in either the Windows Authentication Mode or the SQL Server and Windows Authentication Mode, which is frequently called Mixed Mode 112 SQL Server Security Windows Authentication Mode • Windows Authentication Mode: only logins for valid Windows users are allowed to connect to SQL Server • SQL Server “trusts” the Windows or Active Directory security subsystem to have validated the account credentials 113 SQL Server and Windows Authentication Mode (Mixed Mode) Windows Authentication Mode • In SQL Server Mode and Windows Authentication Mode, or Mixed Mode, valid Windows accounts and standard SQL Server logins are permitted to connect to the server • SQL Server logins are validated by supplying a username and password Windows accounts are trusted by SQL Server 114 Questions Định nghĩa thuật ngữ: sở liệu, hệ quản trị sở liệu, hệ sở liệu, từ điển sở liệu, mơ hình sở liệu Nêu tính chất sở liệu Nêu chức hệ quản trị sở liệu Giải thích đặc trưng giải pháp sở liệu Định nghĩa mô hình sở liệu phân loại Liệt kê người có liên quan đến hệ sở liệu 115 116

Ngày đăng: 03/07/2023, 16:36

Tài liệu cùng người dùng

Tài liệu liên quan