КОРРЕКТНОСТЬ ТЕХНИКИ ДВУХФАЗНОГО БЛОКИРОВАНИЯ  ДЛЯ РАСПИСАНИЯ С ОБЩИМИ И МОНОПОЛЬНЫМИ БЛОКИРОВКАМИ

Михаил Алексеевич Савин; Сергей Дмитриевич Махортов

doi:10.17308/sait/1995-5499/2025/3/172-179

Authors

Mikhail A. Savin Voronezh State University https://orcid.org/0009-0009-2525-2179 (unauthenticated)
Sergey D. Makhortov Voronezh State University https://orcid.org/0000-0001-6362-4468 (unauthenticated)

DOI:

https://doi.org/10.17308/sait/1995-5499/2025/3/172-179

Keywords:

database systems, ACID, transaction, locking mechanism, transaction schedule, database consistency, two-phase locking

Abstract

Relational databases are one of the most popular solutions for storing structured data. Modern database management systems have various system components that maintain data integrity, security, and durability. Transactions are used to guarantee the correct execution of operations on the database. In addition to satisfying the atomicity, consistency, isolation, and durability principles, DBMSs must also provide additional mechanisms to preserve the consistent state of database elements under various isolation levels in a concurrent environment.This article examines the principles of transaction management used to ensure the integrity of a re lational database. These principles are based on concepts of scheduling and locking. Properly constructed lock-based schedules prevent concurrency issues caused by simultaneous access of multiple transactions to shared data. To achieve this, various locking protocols are used to regulate locks acquisition and release during transaction execution. As a result, the transaction isolation requirement is satisfied within the system. The main part of this study considers transaction mechanisms and schedule construction, as well as the two-phase locking protocol (2PL). T he main objective of this research is to analyze the correctness of 2PL protocol when using two types of locks — shared and exclusive. The results demonstrate that this protocol can be correctly applied to sets of different lock types, offering a foundation for its application with diverse lock types and encouraging further development of the 2PL method.

Author Biographies

Mikhail A. Savin, Voronezh State University

First-year PhD student at the Programming and Information Technologies Department
Sergey D. Makhortov, Voronezh State University

Doctor of Science, Head of the Programming and Information Technologies Department

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