When most database programmers refer to a transaction, they are referring to an ACID transaction. These transactions (logical unit of work) are designed for short-lived decisions usually lasting under a few seconds.

These transactions identify a logical unit of work that is either performed in complete or not at all. That is, either a COMMIT or a ROLLBACK is performed on the operations. This enables the data to maintain a state of consistency.

ACID is an acronym:

• A = Atomic – Transactions are atomic (all or none)
• C = Consistency – A consistent state of the database may be expected at all times.
• I = Isolation – Transactions are isolated from another; race conditions ensure that multiple transaction instances attempts do not collide.
• D = Durable – Once a transaction commits, it’s updates survive even, if the system goes down.

ACID Transactions are described in the GXA via the WS-Transaction specification. WS-Transaction refers to ACID transactions as, “atomic transactions”.