(1) In DB2 for i5/OS SQL, a characteristic of database data definition functions that allows the function to complete or return to its original state if a power interruption or abnormal end occurs.
(2) In commitment control, a characteristic that allows individual changes to objects to appear as a single change.
(3) Pertaining to a transaction's changes to the state of resources: either all occur or none occur. The atomic characteristic maintains data integrity by making sure that some updates are not made while others fail. See also commit.