Analyzing Your Requirements and Source Data

To ensure that you develop an effective business intelligence model, we recommend that you begin by carefully analyzing your users, the OLAP reports they require, and your source data.

Use the following questions to analyze your users' OLAP reporting needs:

  • What reports do users currently use? Which reports do they use most frequently? Which reports do they use only rarely?
  • Does each group require different reports? Are there some reports that are required by all user groups?
  • Do users need higher-level (summary) reports, detailed drill-through reports, or both?
  • How frequently are the measures in the report updated? How frequently do the reports themselves change? Does the frequency vary from group to group?
  • How often are reports required? Can you trade off frequency to ensure accuracy? For example, if your users ask for monthly reports and the data source is refreshed weekly, the data will always be current. However, if your users want daily reports, the data will only be up to date on the first day of the weekly cycle.

Analyze your source data, using questions such as the following:

  • Does the data come from one source or many? What format is it in: flat files, spreadsheets, or databases? Does it need to be converted to a supported data source type before it is imported?
  • Can you optimize existing queries by building new Cognos® Transformer queries using the metadata modeled in IBM® Cognos packages or reports?
  • How many records are there? By how much do you expect the volume of data to increase?
  • How much of the data is static and how much changes gradually over time? Can you create different data sources for static and non-static data to support incremental updates (an option that shortens cube creation time by appending new data to a cube instead of recreating it)?
  • How much data preparation is required?

    Ensure that the source values that feed the categories are unique and, if feasible, that you aggregate or otherwise preprocess your data before importing it. For more information, see Preprocessing Your Data.

  • Are linked measures from different data sources updated at the same time?
  • Must you create additional data sources to accurately model your organization?

When you have answered these questions, you are ready to begin preparing your source data for import and designing your prototype.