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Physical Sciences and Mathematics Commons™
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Full-Text Articles in Physical Sciences and Mathematics
A Concurrency Control Algorithm For An Open And Safe Nested Transaction Model, Sanjay Kumar Madria
A Concurrency Control Algorithm For An Open And Safe Nested Transaction Model, Sanjay Kumar Madria
Computer Science Faculty Research & Creative Works
We present a concurrency control algorithm for an open and safe nested transaction model. We use prewrite operations in our model to increase the concurrency. Prewrite operations are modeled as subtransactions in the nested transaction tree. The subtransaction which initiates prewrite subtransactions are modelled as recovery point subtransaction. The recovery point subtransaction can release their locks before its ancestors commit. Thus, our model increases the concurrency in comparison to other nested transaction models. Our model is useful an environment of long-running transactions common in object oriented databases, computer aided design and in the software development process
User Defined Prewrites For Increasing Concurrency In Design Databases, Sanjay Kumar Madria, A. Embong
User Defined Prewrites For Increasing Concurrency In Design Databases, Sanjay Kumar Madria, A. Embong
Computer Science Faculty Research & Creative Works
We introduce a prewrite operation before a write operation is performed on design databases, a database that consists of objects as engineering designs. A prewrite operation does not actually make a design but it only makes available the model of the design that the transaction will produce in future. Once the prewrite design by a transaction is announced, the transaction executes a pre-commit operation. After the pre-commit, read operations can access the prewrite design even before the pre-committed transaction has finally made the design and committed. Therefore, our algorithm increases the potential concurrency as compared to the algorithms that permit …