Thanks for the reply. Unfortunately, this solution will not help me. It does not create an index global. Probably because I use several superclasses.

Thanks for the reply. Unfortunately, this solution will not help me. I want to extend some classes by inheriting them from other classes (with some properties, methods, indexes). This property inheritance adds this data to the storage (global ^ xD). But the index is not stored in ^ xI because it is not the first superclass.

SELECT
CASE
  WHEN Field1 = 1 THEN 'ONE'
  WHEN Field1 = 2 THEN 'TWO'
  ELSE NULL
END
FROM MyTable