ACCA P 3.4 Practice makes perfect

 [P3.4]Practice makes perfect 

 文章来源：伦敦会计学院 供稿
ACCA paper 3.4 - get the answers to the questions set in PQ Magazine

(Questions set in the May issue of PQ Magazine)

SUGGESTED SOLUTION TO QUESTION ONE

On line analytical processing (OLAP) database systems are generally 　seen as a solution to an issue with conventional relational database systems. 

Relational database systems use a form. of database organisation that 　consists of storing data in two-dimensional tables or computer files. The columns of the tables consist 　of a key or keys that are the unique identifiers of data items followed by　 the descriptive attributes or fields of the file. The fields are in a one to one relation 　with the key each row being unique. The tables are joined by sharing 　common keys often as attributes or common keys. 

The relational database model scores highly on efficiency since data is 　stored once and once only and also scores highly on flexibility since ad-hoc reports are relatively easy to create and self-design. However the relational model sometimes creates slow retrieval of data.

To speed up the retrieval of data in reports an on line processing approach 　is used whereby the transactions details are stored in traditional database 　tables but are also used to update a second database – the OLAP database.

The OLAP database contains a variety of data views or report forms that 　focus on key management information system (MIS) information report formats. 　The OLAP database does not contain the detail of transactions only the totals and sub-totals required to produce the reports. 

Managers are usually given a multi-dimensional view of costs and revenues analysed by, for example 

* Profit centres and cost centres
* Cost type – fixed and variable
* Cost nature – rent, rates etc
* Brand
* Product 

Managers can quickly build reports that are flexible but within the anticipated multi-dimensional view parameters. 

The key objective of OLAP is therefore to create an MIS that gives both speed 　and flexibility of reporting.

SUGGESTED SOLUTION TO QUESTION TWO

The Ward & Peppard grid is most commonly used as a tool for modelling 　and deciding upon candidate information systems for inclusion in a strategically 　determined portfolio of existing systems maintenance and new systems construction.

The grid is largely based around a lifecycle view of how information systems 　pass from new technology research and development into implementation of 　projects and learning how to gain benefits, through to enhancement, upgrading 　and other maintenance of existing systems ending with maintenance and 　enhancement of legacy systems.

Underlying the grid is the view that IS and IT are strategic weapons that have 　the potential for strategic returns in addition to economic returns. The grid also 　includes a view of project, technology and benefit realisation risks. By plotting 　information systems and work on to the grid projects may be classified and a view 　of the whole portfolio examined. The portfolio view enables considerations of how 　to balance the essential issues of return, risk and our capability to build and maintain 　systems within the right timescale.

The Ward & Peppard grid classification includes:

1. High potential developments – new technologies that are essentially at the research and development stage 　but with the potential for future competitive advantage.
2. Strategic projects – current and available technologies that if properly managed and implemented 　may lead to competitive advantage
3. Key operational systems – existing systems that give competitive advantage and may require adaptive 　(and other) maintenance effort to protect them
4. Legacy support systems – former key operational systems that no longer give competitive advantage but 　may require perfective and other forms of maintenance
5. Support technologies – are newly proposed IS projects that involve systems that inherently do not give 　competitive advantage but may give economic or operational benefits

The key to success is to plan a mix of projects and work that represents a 　feasible portfolio and where individual project feasibility is achieved. 

The McFarlan strategic grid is related to but different from its successor the 　Ward & Peppard grid. The McFarlan grid labels organisations according to how 　strategic their overall information systems portfolio is – it shows overall the extent of strategic use of existing systems and whether 　the future systems portfolio will be seen as strategic.

The McFarlan grid indicates the scale of information management issues for a company – what McFarlan describes as a contingency view. The important issue is to know 　where you are on the grid and where you want to be on the grid – or better where you should be on the grid. Management can then consider 　strategies to move the company forward if required. 

The four quadrants on the grid represent:

1. Support – where IS and IT are not critical to advantage
2. Factory – where some existing systems in the portfolio are critical to operations and advantage 
3. Turnaround – where the existing view of IS and IT is as support but new developments 　are critical to future success and advantage 
4. Strategic – where existing systems and future systems are both critical to success and advantage

Making a move on the grid will require funding, resources and effective management 　of projects to which management must be committed. 

With thanks to Peter Keeling of London College of Accountancy 

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