For purposes of IBM® Cognos® Business Intelligence integration with background searches, a background search produces two main types of result tables: fact tables and dimension tables.
Dimension tables have a primary key with a corresponding foreign key value that is stored in the fact table. The relationship between the primary key and foreign key does not have to be enforced because Cognos reporting tools can assign the relationship through the modeling definitions.
Fact tables | The fact table is the table in which the background search query stores the search results. Each cell of an OLAP cube holds a measure (such as sales or profits) that is derived from a fact table. You might rely on Cognos Business Intelligence post-processing to perform any needed aggregation of fact table data. An optional alternative for performing data aggregation is the use of aggregate functions in the search query. Some examples of aggregate functions are COUNT, MAX, MIN, and SUM. |
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Dimension tables | The summarization of OLAP factual data occurs along dimensions (such as time or region)
that are derived from dimension tables. Cognos Business Intelligence can
analyze multidimensional data (measures by dimensions) interactively from multiple
perspectives, including the following ones:
Dimension tables can be created or populated in the following ways:
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