P.A. Bernstein, D.W. Shipman, and W.S. Wong. Formal aspects in serializability in database concurrency control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....execute concurrently. Correctness criteria and protocols have been developed to ensure that a concurrent execution of a set of transactions is equivalent to some serial execution of the same set of transactions. This noticon of equivalence to a serial execution is referred to as serializability [4, 7, 29], and is widely accepted as the cornerstone of database correctness. Recently, the scope of database systems has expanded to include new applications such as CAD CAM databases and cooperative developmenl; environments. These applications have necessitated a teevaluation of serializability as the ....

....called orderability and found that testing if a history is orderable is NP complete. This prompts a search for alternative correctness conditions that are efficiently recognizable and implementable. One such notion is strong orderability that is obtained by generalizing conflict serializability [4, 29] in two ways. First, we extend conflict serializability to include the idea of consistency assertions. Second, instead of using equivalence of histories based on commutativity of operations, we use reductions based on one way commutativity of operations. A similar notion has been used for ....

BERNSTEIN, P. A., SHIPMAN, D. W., AND WONG, W. S. Formal aspects of serializability in database concurrency control. IEEE Truns. Softw. Eng. 5 5 (May 1979), 203-216.

.... that no more transactions with timestamps in a certain range will arrive at a given node) or will abort more transactions (a transaction with an early timestamp may not be runnable at a given node because a transaction with a later timestamp has already committed) Bernstein, Shipman, and Wong [BSW79] have examined different methods of insuring serializability. Their formal analysis indicates that timestamping may provide more concurrency than two phase locking. However, their paper investigates concurrency without examining other effects such as waiting, deadlock, and the number of ....

....to special case read only transactions to achieve a simpler solution to the problem. 8.2.9 Evaluation. As noted in Chapter 7, there is no hard data available for comparing distributed transaction schemes, or even specific techniques. Some speculative works have bccn published (e.g. BG80, BSW79] and a vadety of claims have been made concerning different schemes. It would be very useful if experiments were performed comparing designs similar enough to each other to allow strong conclusions to be drawn. To make such comparisons well would require building two systems that are the same ....

Philip A. Bernstein, David W. Shipman, Wing S. Wong, "Formal Aspects of Serializability in Database Concurrency Control", IEEE Trans. on Soft. Eng., Vol. SE-5, No. 3, pp. 203-216, May 1979.

....detection strategy, continuous or periodic, to optimize system performance, when given a set of system characteristics. Received May 5, 1995; revised September 12, 1995 1. INTRODUCTION Many existing transaction database systems such as IBM s DB2 and RTI s INGRES ensure serializable executions [1, 2] by running a version of two phase locking (2PL) 3] in which a transaction consisting of a sequence of access operations should obtain a lock before accessing a data item controlled by the lock and should release all of the locks it owns together when it terminates. A nice property of 2PL is that ....

Bernstein, P. A., Shipman, D. W. and Wong, D. W. (1979) `Formal aspects of serializability in database concurrency control.' IEEE Trans. Software Eng. 5, 203--216.

....accepts a strict subset of SOT. However, we note that the SOT histories that are not accepted by this protocol are not order preserving serializable histories 4 . 4 Order preserving serializable histories maintain the order of non interleaved transactions in the equivalent serial history [BSW79, BBG89] 5 Conclusions In this paper, we have addressed an open problem posed by [SWY93] how to characterize the class of histories PRED in a constructive way so that unified scheduling protocols can be derived from it. We have slightly modified the original definitions of expanded histories ....

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

.... the the problem of cascading aborts, both for read and write operations, a restricted form of ordered sharing can be used where non shared locks are used from writers 1 Order preserving serializable histories maintain the order of non interleaved transactions in the equivalent serial history [10, 5]. to both readers and writers and locks are released only when transactions terminate. Hence, a non shared relationship from write locks to both read and write locks is used in this protocol. For write after read conflicts, locks with ordered sharing are used and transactions must adhere to the ....

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203-- 216, May 1979.

....database systems is to maintain entire transactions as single atomic units with respect to each other. Such atomicity of transactions is enforced in most commercial database systems by ensuring that the interleaved execution of concurrent transactions remains serializable [EGLT76, RSL78, Pap79, BSW79] Databases are increasingly used in applications, where transactions may be long lived, or where transactions correspond to executions of various users cooperating with each other, e.g. in design databases, CAD CAM databases, etc. For such applications serializability is found to be too ....

....of the transactions in T such that the operations of transaction T i appear in the same order in S as they do in T i , for i = 1; n. In order to relate schedules over the same set of transactions, the notion of conflict between operations is used in concurrency control theory [Pap79, BSW79] Two operations of different transactions conflict if they access the same data object and at least one of them is a write operation. Two schedules are conflict equivalent if they both order conflicting operations in the same manner. Our motivation in this paper is to generalize the transaction ....

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P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

....is to synchronize access to shared resources in such a way that the overall effect is as if the actions had been run sequentially even through concurrent execution is actually taking place. Algorithms One of the most popular techniques for implementing serializability is two phase locking [BSW79, EGLT76, Pap79] In this scheme, a lock is associated with each shared resource, with the requirement that a lock be acquired prior to any access of the associated resource. The action is further constrained in the order in which it can acquire and release locks to go through two distinct phases. ....

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal aspects of serializability in database concurrency control. IEEE Transactions on Software Engineering, SE-5(3):203--216, May 1979.

....in the traditional serializability model) To capture the various ways in which co actions can interfere with each other, we need to introduce the notions of conflict and dependency . The notion of conflict between operations is used in the traditional concurrency control theory [Pap79, BSW79] Two operations of different co actions conflict if they access the same data object and at least one of them is a write operation. Two executions are conflict equivalent if they both order conflicting operations in the same manner. For collaborative databases, we need to define an additional ....

....Thus, the notion of dependency is used in such a way that the relative atomicity specifications are enforced only when it is necessary, i.e. when co actions affect each other. The notion of relatively serial executions is analogous to the notion of serial executions in serializability theory [BSW79, Pap79] In particular, there exist executions that are not relatively serial but may have the same behavior as some relatively serial executions. We define an execution to be relatively serializable [ABEK94] if it is conflict equivalent to some relatively serial execution. For example, the ....

[Article contains additional citation context not shown here]

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

....at the same time, a large number of queries are often made to support business decisions. Therefore, a database system that can provide a high degree of concurrency is of ultimate importance. The read=write model has been the traditional data model for database applications and serializability [5, 7, 15] is used to ensure the correctness of interleaved executions of transactions. The strict two phase locking protocol [7] is widely used in commercial products to enforce serializability. However, recently this model has been found to be too restrictive for modeling advanced applications such as ....

....strict two phase locking protocol is illustrated. 2.1 Read Write Model The read=write model models a database by a collection of data objects which can only be read or written by transactions. This model has been the traditional data model for relational database applications. Serializability [5, 7, 15] is widely used to ensure the correctness of interleaved executions of transactions. The fundamental idea of serializability is to ensure that an interleaved execution of transactions is equivalent to a serial execution where an execution is serial if for every two transactions, say T 1 and T 2 , ....

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

....transactions to execute concurrently and employ a concurrency control protocol to ensure that the effects of interleaved execution of transactions is the same as if the transactions were executed serially. A commonly accepted correctness criterion for interleaved executions is serializability [7, 20, 5]. Databases are increasingly being used to model non standard applications, and serializability is found to be too restrictive in such applications [3] Researchers, in general, have taken two different approaches to address this problem. Instead of modeling the database as a collection of objects ....

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

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P.A. Bernstein, D.W. Shipman, and W.S. Wong. Formal aspects in serializability in database concurrency control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

No context found.

P. A. Bernstein, D. W. Shipman, and W. S. Wong. Formal Aspects of Serializability in Database Concurrency Control. IEEE Transactions on Software Engineering, 5(5):203--216, May 1979.

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