Determining Business, User, and Technical Requirements

Before a data warehouse can be built, a detailed project and implementation plan should be written. The project and implementation plan includes:

• Building a business case.
• Gathering user requirements.
• Determining the technical requirements.
• Defining standard reports required by users.
• Analyzing client application tools being used.

Building the business case is common at the beginning of any project. It involves determining the business needs solved by the project, the costs of the project, and the return on the investment.

Gathering user requirements largely involves interviewing the intended users of the data warehouse. The user requirements determine:

• Data requirements (level of granularity).
• Operational systems within the enterprise containing the data.
• Business rules followed by the data.
• Queries required to provide the users with data.

The technical requirements may involve determining:

• Hardware architecture and infrastructure (for example, links to remote geographical regions where data marts might be located).
• Backup and recovery mechanisms.
• Security guidelines.
• Methods of loading and transforming data from operational systems to the data warehouse.

Standard reports required by users should be analyzed to determine the tables, columns, and selection criteria necessary to create the reports, and the frequency in which they are generated. Provisions should also be made for expanding or modifying the scope of reports as required.

Client application tools should be analyzed to determine if they can provide enhanced processing capabilities that help in processing data, performing queries, or generating reports.