chapter 11
Four factors have contributed to the growth of the commercial software market:
(1) the relatively low cost of general commercial software as compared to customized software; (2) the emergence of industry specific vendors who target their software to the needs of particular types of businesses (3) a growing demand from businesses that are too small to afford in house systems' development staff (4) The trend toward downsizing organizational units and the move toward distributed data processing has made the commercial software option appealing to larger organizations are completely finished and tested systems that are ready for implementation.
phased in
-It is particularly suited to diversified organizations whose units do not share common processes and data. -independent ERP systems can be installed in each business unit over time to accommodate the adjustment periods needed for assimilation.
data mart
-is a data warehouse organized for a single department or function. •Rather than containing hundreds of gigabytes of data for the entire enterprise, a data mart may have only tens of gigabytes of data. •Other than size, we make no distinction between a data mart and a data warehouse.
access control list (ACL)
-is a list containing information that defines the access privileges for all valid users of the resource. -An access control list assigned to each resource controls access to system resources such as directories, files, programs, and printers.
payback method
-is a variation of break-even analysis. -Under the payback method, the break-even point is reached when total costs equal total benefits.
Enterprise resource planning (ERP)
-systems are assembled from prefabricated software components -are multiple module software packages that evolved primarily from traditional manufacturing resource planning (MRP II) systems
two-tier model
-the server handles both application and database duties. -Client computers are responsible for presenting data to the user and passing user input back to the server.
three tier model
-where the database and application functions are separated. -This architecture is typical of large ERP systems that use wide area networks (WANs) for connectivity among the users.
The data warehousing process has the following essential stages:
1.Modeling data for the data warehouse 2.Extracting data from operational databases 3.Cleansing extracted data 4.Transforming data into the warehouse model 5.Loading data into the data warehouse database
object oriented approach
Build information systems from reusable standard components or objects
Control
By keeping modules small, they are less likely to contain material errors of fraudulent logic
Programming efficiency
Modules can be coded and tested independently
Backbone systems
Provide a basic system structure on which to build
Maintenance efficiency
Small modules are easier to analyze and change
project schedule
a budget of the time and costs for all the phases of the SDLC and represents management's commitment to the project.
client/server model
a form of network topology in which a user's computer or terminal (the client) accesses the ERP programs and data via a host computer called the server.
user handbook
a reference manual of commands for getting started.
The systems development process constitutes
a set of activities by which organizations obtain IT-based information systems.
one of the most critical control issues in an ERP environment.
access security
The systems development process activities are of interest to
accountants and auditors
online analytical processing (OLAP)
an enterprise resource planning decision support tool used to supply management with real time information. -It also permits timely decisions that are needed to improve performance and achieve a competitive advantage.
systems evaluation and selection phase
an optimization process that seeks to identify the best system.
Using Internet technologies and OLAP applications
an organization can share its data warehouse with its trading partners and, in effect, treat them like divisions of the firm.
Turnkey systems
are completely finished and tested systems that are ready for implementation.
Office automation systems
are computer systems that improve the productivity of office workers.
General accounting systems
are designed to serve a wide variety of user needs.
stakeholders
are entities either inside or outside an organization that have a direct or indirect interest in the firm
Online transaction processing (OLTP)
are events consisting of large numbers of relatively simple transactions such as updating accounting records that are stored in several related tables.
Systems professionals
are systems analysts, designers, and programmers who have expertise in the specific areas that the feasibility study covers
core applications
are those applications that operationally support the day today activities of the business. •Sales and Distribution •Business Planning •Production Planning •Shop floor control •Logistics
End users
are those for whom the system is built
Systems maintenance
constitutes the organization's program change procedures: It begins once the seven phases are completed and the system is fully implemented.
ERP functionality falls into two general groups of applications:
core applications and business analysis applications.
data warehouse
database constructed for quick searching, retrieval, ad hoc queries, and ease of use
system implementation phase of the systems development process
database structures are created and populated with data, equipment is purchased and installed, employees are trained, the system is documented, and the new system is installed.
systems selection report
deliverable portion of the systems selection process that will go to the next phase
A data warehouse is composed of both
detail and summary data.
structure diagram
diagram that divides processes into input, process, and output functions
run manual
documentation describing how to run the system.
drill down capability
enables users to view details, and details of details, of information useful data analysis technique associated with data mining.
Legal feasibility
ensures that the proposed system is not in conflict with the company's ability to discharge its legal responsibilities.
The process of data warehousing involves
extracting, converting, and standardizing an organization's operational data from ERP and legacy systems and loading them into a central archive the data warehouse.
Total cost of ownership (TCO) includes
hardware, software, consulting services, internal personnel costs, installation, and upgrades and maintenance to the system for the first two years after implementation.
Tangible benefits fall into two categories:
hose that increase revenue and those that reduce costs
Intangible benefits
improve customer satisfaction
The ERP implementation team
includes key users and information technology (IT) professionals, selects specific database tables and processes by setting switches in the system.
New systems development
involves conceptual steps that can apply to any problem-solving process: •identify the problem •understand what needs to be done •consider alternative solutions •select the best solution •finally, implement the solution.
Data cleansing
involves filtering out or repairing invalid data prior to being stored in the warehouse. transforming data into standard business terms with standard data values.
Strategic systems planning
involves the allocation of systems resources at the macro level and often deals with a time frame of three to five years.
role
is a formal technique for grouping together users according to the system resources needed to perform their assigned tasks
role-based access control (RBAC)
is a formal technique for grouping users according to the system resources they require to perform their assigned tasks.
data warehouse
is a relational or multidimensional database that may consume hundreds of gigabytes or even terabytes of disk storage.
changed data capture
is a technique that can dramatically reduce extraction time by capturing only newly modified data.
big bang
is an attempt by organizations to switch operations from their old legacy systems to a new system in a single event that implements the ERP across the entire company.
iterative approach
is associated with SDLC where small "chunks" or modules cycle through all ofthe SDLC phases rather rapidly, with a short time frame from beginning to end.
A key feature of a data warehouse
is that the data contained in it are in a nonvolatile, stable state
An OLAP transaction
is the aggregation of sales data by region, product type, and sales channel.
Walk-through
is the analysis of system design to ensure the design is free from conceptual errors that could become programmed into the final system.
Technical feasibility
is the determination of whether the system can be developed under existing technology or if new technology is required.
Systems analysis report
is the formal report that marks the conclusion of the systems analysis phase
Net present value method
is the method in which the present value of the costs is deducted from the present value of the benefits over the life of the system.
Data extraction
is the process of collecting data from operational databases, flat files, archives, and external data sources.
The purpose of project planning
is to allocate resources to individual applications within the framework of the strategic plan.
The purpose of project planning
is to allocate resources to individual applications within the framework of the strategic plan. •involves : •identifying areas of user needs, •preparing proposals •evaluating each proposal's feasibility and contribution to the business plan, •prioritizing individual projects ,•scheduling the work to be done
The objective of systems planning
is to link individual system projects or applications to the strategic objectives of the firm.
The primary reason for data warehousing
is to optimize business performance.
conceptual design phase
is to produce several alternative conceptual systems that satisfy the system requirements identified during systems analysis
OLAP applications support
management critical tasks through analytical investigation of complex data associations that are captured in data warehouses.
project proposal provides
management with a basis for deciding whether to proceed with the project.
OLTP applications support
mission critical tasks through simple queries of operational databases.
Fact Gathering Techniques
observation, task participation, personal interviews, reviewing key documents
Economic feasibility
pertains to the availability of funds to complete the project.
Operational feasibility
pertains to the degree of compatibility between the firm's existing procedures and personnel skills and the operational requirements of the new system.
The purpose of the detailed design phase
produce a detailed description of the proposed system that both satisfies the system requirements identified during systems analysis and is in accordance with the conceptual design.
Schedule feasibility
relates to the firm's ability to implement the project within an acceptable time.
detailed design report
set of blueprints that specify input screen formats, output report layouts, database structures, and process logic.
Supply chain management (SCM)
software is a class of application software that supports the set of activities associated with moving goods from the raw materials stage through to the consumer.
Bolt-on software
software provided by third party vendors used in conjunction with already purchased ERP software
two methods of conceptual design phase
structured designed, object designed
The participants in systems development may be classified into three broad groups:
system professionals, end users, and stakeholders
role-based governance
systems that allow managers to view current and historical inventory of roles, permissions granted, and individuals assigned to roles; identify unnecessary or inappropriate access entitlements and segregation-of-duties violations; and verify that changes to roles and entitlements have been successfully implemented.
Vendorsupported systems
systems that the vendor develops and maintains for the client organization.
extraction software compares
the current operational database with an image of the data taken at the last transfer of data to the warehouse. Only data that have changed in the interim are captured
System survey
the determination of what elements, if any, of the current system should be preserved as part of the new system
Systems development life cycle (SDLC)
the software development process.
Scalability
the system's ability to grow smoothly and economically as user requirements increase.
break-even point
total costs equal total benefits
Data flow diagrams (DFDs)
use of a set of symbols in a diagram to represent the processes, data sources, data flows, and process sequences of a current or proposed system.
WHY PERFORM STRATEGIC SYSTEMS PLANNING ?
•Resolving conflicts that arise from new systems •Reviewing projects and assigning priorities •Budgeting funds for systems development •Reviewing the status of individual projects under development •Determining at various checkpoints throughout the SDLC whether to continue with the project or terminate it
Organizations acquire information systems in two ways:
•They develop customized systems in house through formal systems development activities. •They purchase commercial systems from software vendors.
OLAP servers support common analytical operations:
•consolidation, •drill down •slicing and dicing.
Develop Performance Measures
•reductions in inventory levels •inventory turnover •stock-outs •average order fulfillment time that reflect its expectations
Modular Programming
This technique produces small programs that perform narrowly defined tasks.