The use of database system in computer-aided design environments leads to new requirements for the trannsaction management. Transactions in such environments are usually long lived and cooperative.
This paper proposes a recovery scheme for CADTM, a database transaction manager for coordianting design activities in CAD environments, which has proposed by Cho and Moon at KAIST. In this model, a transactin is a sequence of operation such as the running of a CAD tool. In order to guarantee failure atomicity of a transaction, most conventional recovery schemes undo all execution results when a failure occurs, and do not commit partial execution results of the transaction. This means that all work done are lost in care of various types of failure. In addition, cooperation between transaction is difficult. Therefore, conventional recovery schemes are not appropriate for these long-lived and cooperative CAD transactions.
In our recovery scheme for CADTM, the concept of persistent savepoint is facilitated to externalize partial execution results, and forward recovery technique is used not to destroy entire transaction results when a failure occurs.
