By default, or when
you specify AGGREGATE=NO, aggregate data items in the information
map are not accessible through the Information Maps engine. If an
information map contains such data items, then a warning is displayed
in the SAS log indicating how many data items are not accessible.
Specify AGGREGATE=YES to retrieve aggregated data.
When you specify AGGREGATE=YES
and use the CONTENTS procedure to view the contents of an information
map, a column named Default Aggregation appears in the procedure output
showing the default aggregation function that is assigned to the variable.
If the original variable was character type, it is changed to numeric
type due to applying the aggregation function. For example, a default
aggregation function of COUNT on a character variable containing names
produces a numeric variable that contains the number of names. A line
in the heading of the CONTENTS procedure output shows the number of
aggregate variables, if any.