Creating indexes is a minimally-logged database operation. Serial sorts are recovered from the transaction log by completely redoing the sort. However, parallel create index commands are not recoverable from the transaction log—after performing a parallel sort, you must dump the database before you can use the dump transaction command on the database.
Adaptive Server does not automatically perform parallel sorting for create index commands unless the select into/bulk copy/pllsort database option is set on. Creating a clustered index on a partitioned table always requires a parallel sort; other sort operations can be performed in serial if the select into/bulk copy/pllsort option is not enabled.