TAILIEUCHUNG - Lecture Fundamentals of database systems: Chapter 9 - Emasri, Navathe

After completing this chapter, students will be able to understand: Specification of more general constraints via assertions, SQL facilities for defining views (virtual tables), Various techniques for accessing and manipulating a database via programs in general purpose languages. | General Constraints as Assertions Views in SQL Database Programming Embedded SQL Functions Calls SQL CLI Stored Procedures SQL PSM Summary Specification of more general constraints via assertions SQL facilities for defining views virtual tables Various techniques for accessing and manipulating a database via programs in generalpurpose languages . Java C etc. Copyright 2007 Ramez Elmasri and Shamkant B. Navathe lide 9- 3 Copyright 2007 Ramez Elmasri and Shamkant B. Navathe lide 9-4 General constraints constraints that do not fit in the basic SQL categories presented in chapter 8 Mechanism CREAT ASSERTION Components include a constraint name followed by CHECK followed by a condition Copyright 2007 Ramez Elmasri and Shamkant B. Navathe Slide 9- 5 The salary of an employee must not be greater 1 Specify a query that violates the condition include inside a NOT EXISTS clause Query result must be empty if the query result is not empty the assertion has been violated Triggers are expressed in a syntax similar to assertions and include the following Event Such as an insert deleted or update operation Condition Action To be taken when the condition is satisfied Copyright 2007 Ramez Elmasri and Shamkant B. Navathe lide 9 Copyright 2007 Ramez Elmasri and Shamkant B. Navathe Slide 9- 8 A trigger to compare an employee s salary to his her supervisor during insert or update operations CREATE TRIGGER INFORM_SUPERVISOR BEFORE INSERT OR UPDATE OF SALARY SUPERVISOR_SSN ON EMPLOYEE FOR EACH ROW WHEN SELECT SALARY FROM EMPLOYEE WHERE SSN INFORM_SUPERVISOR A view is a virtual table that is derived from other tables Allows for limited update operations Since the table may not physically be stored Allows full query operations A convenience for expressing certain operations Copyright 2007 Ramez Elmasri and Shamkant B. Navathe lide 9- 9 SQL command CREATE VIEW Copyright 2007 Ramez Elmasri and Shamkant B.

• Cơ sở dữ liệu
• Database systems
• Fundamentals of database systems
• Database programming
• Embedded SQL
• Functions calls
• Stored procedures
• Lecture Database Systems
• Database systems concepts
• Database systems architecture
• Database languages
• Data management systems framework
• Introduction to Database Systems
• Database system concepts
• Entity Relationship model
• Database security
• Distributed database systems
• Principles of distributed database systems
• Cơ sở dữ liệu phân tán
• Parallel database systems
• Load balancing
• Database architecture
• Database approach
• Database management systems
• Lecture Database management systems
• File based system
• Characteristics of the database
• Data dictionary
• Database integration
• Schema matching
• The relational data model
• Database design
• Database programming techniques
• Relational database constraints
• Database System
• Relational databases
• Relational database design algorithms
• Relational database systems
• Computer networks
• Practical Database Design
• Physical Database Design in Relational Databases
• An Overview of Database Tuning in Relational Systems
• Physical Database Design Decisions
• Data models
• Hierarchical model
• Designing a set of relations
• Relational decompositions
• Relational database schema
• Database users
• Database applications
• Typical DBMS functionality
• Databases and database users
• Relational calculus
• Physical database design
• Concurrency control techniques
• Database recovery techniques
• Distributed databases
• Multivalued dependencies
• Fundamentals of database management systems
• Logical database design
• Object oriented database management
• Data administration
• Design problem
• Dimensions of the problem
• Database development
• Database environments
• Object database management systems
• Object database
• Bài giảng Hệ quản trị cơ sở dữ liệu
• Operating systems
• Attribute alias
• Lecture Database system concepts
• Database system architectures
• Relational database design