Nested Transaction Models
A nested transaction model as proposed by Moss is a generalization of the flat transaction model that allows nesting. A nested transaction forms a tree of transactions with the root being called a top-level transaction and all other nodes called nested transactions (subtransactions). Transactions having no subtransactions are called leaf transactions. Transactions with subtransactions are called parents (ancestors) and their subtransactions are called children (descendants).
A subtransaction can commit or rollback by itself. However, the effects of the commit cannot take place unless the parent transaction also commits. Therefore, in order for any subtransaction to commit, the top-level transaction must commit. If a subtransaction aborts, all its children subtransactions (forming a subtree) are forced to abort even if they committed locally.
Nested transactions were introduced by Moss in 1981  to overcome some of the limitations of the flat...
- 1.Moss EB. Nested transactions: an approach to reliable distributed computing. Technical Report. PhD Thesis. UMI Order Number: TR-260: Massachusetts Institute of Technology; 1981. p. 178.Google Scholar
- 2.Bjork LA. Recovery scenario for a DB/DC system. In: Proceedings of the ACM Annual Conference; 1973. p. 142–6.Google Scholar
- 3.Davies CT. Recovery semantics for a DB/DC system. In: Proceedings of the ACM Annual Conference; 1973. p. 136–41.Google Scholar
- 5.Reed DP. Naming and synchronization in a distributed computer system. Technical Report. PhD Thesis, UMI Order Number: TR-205: Massachusetts Institute of Technology; 1978. p. 181.Google Scholar
- 8.Eppinger JL, Mummert LB, Spector AZ. Camelot and Avalon: a distributed transaction facility. San Mateo: Morgan Kaufmann Publishers; 1991.Google Scholar
- 9.Elmagarmid AK. Database transaction models for advanced applications. San Mateo: Morgan Kaufmann Publishers; 1992.Google Scholar
- 11.Weikum G, Schek H-J. Multi-level transactions and open nested transactions. Q Bull IEEE TC Data Eng. 1991;14(1):60–6.Google Scholar
- 12.Weikum G, Schek HJ. Concepts and applications of multilevel transactions and open nested transactions. In: Database transaction models for advanced applications. San Mateo: Morgan Kaufmann Publishers; 1992. p. 515–53.Google Scholar