Sets in Planning
You can use sets when planning in the Special Purpose Ledger.
A set links together specific values or ranges of values under a set name. These values exist within one or more dimensions of the FI-SL coding block. A dimension is a single field or column of a table. Account, cost center, and business area are examples of dimensions.

If you use sets in planning, you must create the sets using the database table GLU1.
You can use basic, single-dimension, and multi-dimension sets in planning. You do not need key figure sets, since the currency types and plan periods are already defined in your plan
parameters . You use sets within planning to define dimensions for which you can enter plan data and to select the order of the dimensions in a planning hierarchy.
If you want to plan costs for accounts 600000 and 700000 in cost centers 100 and 200, you need to create two basic sets (one for the dimension "Account" and one for the dimension "Cost center"). In the basic set for accounts, you enter accounts 600000 and 700000, and in the basic set for cost centers, you enter cost centers 100 and 200.