You can create indexes on computed columns as though they were regular columns, as long as the datatype of the result can be indexed. Computed column indexes provide a way to create indexes on complex datatypes like XML, text, image, and Java classes.
For example, the following code sample creates a clustered index on the computed columns as though they were regular columns:
CREATE CLUSTERED INDEX name_index on parts_table(name_order) CREATE INDEX adt_index on parts_table(version_order) CREATE INDEX xml_index on parts_table(spec_index) CREATE INDEX text_index on parts_table(descr_index)
SAP ASE evaluates the computed columns and uses the results to build or update indexes when you create or update an index.