tailieunhanh - Lecture Database Systems - Lecture 18
After completing this chapter, students will be able to: Functional Dependencies (FDs), normalization, notes and suggestions. Inviting you to refer lecture for more information. | CSC271 Database Systems Lecture # 18 Summary: Previous Lecture Transactions Authorization Authorization identifier, ownership, privileges GRANT/REVOKE Database Planning, Design, and Administration Chapter 9 Software Depression Last few decades have seen proliferation of software applications, many requiring constant maintenance involving: Correcting faults Implementing new user requirements Modifying software to run on new or upgraded platforms Effort spent on maintenance began to absorb resources at an alarming rate Software Depression As a result, many major software projects were Late Over budget Unreliable Difficult to maintain Performed poorly In late 1960s, led to ‘software crisis’, now refer to as the ‘software depression’ Software Depression Major reasons for failure of software projects includes: Lack of a complete requirements specification Lack of appropriate development methodology Poor decomposition of design into manageable components Structured approach to development was proposed called Information Systems Lifecycle (ISLC) Information System Resources that enable collection, management, control, and dissemination of information throughout an organization Database is fundamental component of IS, and its development/usage should be viewed from perspective of the wider requirements of the organization DB System Development Life Cycle Database planning System definition Requirements collection and analysis Database design DBMS selection (optional) Application design Prototyping (optional) Implementation Data conversion and loading Testing Operational maintenance DB System Development Lifecycle Database Planning Begins with customer request to develop a database system Must be integrated with overall IS strategy of the organization Database Planning Mission statement for the database project defines major aims of database application Those driving database project normally define the mission statement Mission statement helps clarify purpose of . | CSC271 Database Systems Lecture # 18 Summary: Previous Lecture Transactions Authorization Authorization identifier, ownership, privileges GRANT/REVOKE Database Planning, Design, and Administration Chapter 9 Software Depression Last few decades have seen proliferation of software applications, many requiring constant maintenance involving: Correcting faults Implementing new user requirements Modifying software to run on new or upgraded platforms Effort spent on maintenance began to absorb resources at an alarming rate Software Depression As a result, many major software projects were Late Over budget Unreliable Difficult to maintain Performed poorly In late 1960s, led to ‘software crisis’, now refer to as the ‘software depression’ Software Depression Major reasons for failure of software projects includes: Lack of a complete requirements specification Lack of appropriate development methodology Poor decomposition of design into manageable components Structured approach to .
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