Attributes have a text, Boolean, date or numeric type property. Although assigned at the dimension level, the type applies only to the level 0 members of the dimension.
To avoid the possibility of duplicate member names across Boolean, date, and numeric attribute dimensions, you may need to format the member names to include a prefix or a suffix.
If you change the attribute dimension type for an existing dimension with members, the existing level 0 member names may not conform to the rules for the new attribute dimension type. Because it does not know what you want to do with the names of existing members or their associations, Essbase does not remove or rename them. If needed, you must manually remove or rename the names of existing members that do not conform because of a change in attribute dimension type. For more information about attribute types, see the Oracle Essbase Database Administrator's Guide.
The default attribute dimension type is text.
To set the attribute dimension type:
Open the outline in Outline Editor to the Outline tab.
Right-click the attribute dimension and select Edit member properties.
In the Member Properties dialog box, select the Information tab.
In the Dimension type drop-down list, select Attribute.
In the Attribute type drop-down list, select the attribute type.
Click OK.
“Attribute Types” in the Oracle Essbase Database Administrator's Guide
Defining Prefix or Suffix Formats for Members of Attribute Dimensions