Specially prepared information maps provide a metadata layer between the nontechnical
business user and the complexities of database structure and
query languages. Information maps are created by a
data source administrator in a centrally managed location so that you can easily define a report.
Authorized users who might be more advanced can access tables and cubes directly.
All data sources contain data items, which can refer to calculations or physical data
(tables or cubes). Data items in information maps are described in common business
terms that enable both casual and professional report authors to easily build queries
that return consistent results. Reports can include query results from more than one
data source.
Each
information map includes one or more data items. For example, an information map named
Order
Information might include standard data items such
as
Order ID,
Product
ID,
Unit Cost,
Order
Date, and
Order Amount. You decide which data items to use. You can select all of the data items in the
data source or a subset of data items.
You can also create
two types of custom data items:
-
You can calculate a new
measure that is based on one or more existing measures.
-
In addition to explaining
how to use both standard and custom data items, this chapter explains
how to modify the query in these ways:
-
by changing the format used for
one or more data items
-
by using
detail data instead of grouped and aggregated data
-
by changing the
aggregation method used for one or more measures