DATABASE SYSTEM CONCEPTS instructor: Jingsheng Lei(雷景生) E-mail: ishleiahainu. edu. cn 标 Database System Concepts 1.1 @Silberschatz, Korth and Sudarshan
Database System Concepts 1.1 ©Silberschatz, Korth and Sudarshan DATABASE SYSTEM CONCEPTS instructor: Jingsheng Lei(雷景生) E-mail: jshlei@hainu.edu.cn
Chapter 1: Introduction Applications of Database Systems Database Systems versus File Systems View of data Data Models Database Language Database Users and administrator Transaction Management Database System Structure Application Architectures History of Database Systems Summary 标 Database System Concepts @Silberschatz, Korth and Sudarshan
Database System Concepts 1.2 ©Silberschatz, Korth and Sudarshan Chapter 1: Introduction Applications of Database Systems Database Systems versus File Systems View of Data Data Models Database Language Database Users and Administrator Transaction Management Database System Structure Application Architectures History of Database Systems Summary
Database Management System(DBMS) Collection of interrelated data Set of programs to access the data DB contains information about a particular enterprise DBMS provides an environment that is both convenient and efficient to use Database systems are designed to manage large bodies of information DBS must ensure the safety of the information stored Several users Data Database(DB) Database Management System (DBMS) Database System(DBS) Database System Concepts 1.3 OSilberschatz. Korth and Sudarshan
Database System Concepts 1.3 ©Silberschatz, Korth and Sudarshan Database Management System (DBMS) Collection of interrelated data. Set of programs to access the data. DB contains information about a particular enterprise. DBMS provides an environment that is both convenient and efficient to use. Database systems are designed to manage large bodies of information. DBS must ensure the safety of the information stored. Several users. Data Database(DB) Database Management System (DBMS) Database System(DBS)
1 Applications of Database Systems Database Applications: Banking: all transactions Airlines: reservations, schedules Universities: registration, grades Sales: customers, products, purchases Manufacturing: production, inventory, orders, supply chain Human resources: employee records, salaries, tax deductions Databases touch all aspects of our lives Database System Concepts 1.4 OSilberschatz. Korth and Sudarshan
Database System Concepts 1.4 ©Silberschatz, Korth and Sudarshan 1 Applications of Database Systems Database Applications: Banking: all transactions Airlines: reservations, schedules Universities: registration, grades Sales: customers, products, purchases Manufacturing: production, inventory, orders, supply chain Human resources: employee records, salaries, tax deductions Databases touch all aspects of our lives
2 Database Systems versus File Systems In the early days, database applications were built on top of file systems Drawbacks of using file systems to store data: Data redundancy and inconsistency Multiple file formats, duplication of information in different files Difficulty in accessing data Need to write a new program to carry out each new task Data isolation -multiple files and formats Integrity problems Integrity constraints (e. g account balance >0) become part of program code Hard to add new constraints or change existing ones Database System Concepts 1.5 OSilberschatz. Korth and Sudarshan
Database System Concepts 1.5 ©Silberschatz, Korth and Sudarshan 2 Database Systems versus File Systems In the early days, database applications were built on top of file systems Drawbacks of using file systems to store data: Data redundancy and inconsistency Multiple file formats, duplication of information in different files Difficulty in accessing data Need to write a new program to carry out each new task Data isolation — multiple files and formats Integrity problems Integrity constraints (e.g. account balance > 0) become part of program code Hard to add new constraints or change existing ones