SAP ASE provides SQL standard-compliant “chained” transaction behavior as an option.
In chained mode, all data retrieval and modification commands (delete, insert, open, fetch, select, and update) implicitly begin a transaction. Since such behavior is incompatible with many Transact-SQL applications, Transact-SQL style (or “unchained”) transactions remain the default.
You can initiate chained transaction mode using the set chained option. The set transaction isolation level option controls transaction isolation levels.