Read-only transactions in a distributed database

ABSTRACT

A read-only transaction or query is a transaction which does not modify any data. Read-only transactions could be processed with general transaction processing algorithms, but in many cases it is more efficient to process read-only transactions with special algorithms which take advantage of the knowledge that the transaction only reads. This paper defines the various consistency and currency requirements that read-only transactions may have. The processing of the different classes of read-only transactions in a distributed database is discussed. The concept of R insularity is introduced to characterize both the read-only and update algorithms. Several simple update and read-only transaction processing algorithms are presented to illustrate how the query requirements and the update algorithms affect the read-only transaction processing algorithms.

REFERENCES

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.2 DATABASE MANAGEMENT

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.4 Distributed Systems
          Subjects: Distributed databases

  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.4 Systems
          Subjects: Query processing

General Terms:
Algorithms, Performance

Keywords:
R insularity, concurrency control, consistency, currency, query, read-only transaction, schedule, serializability, transaction, transaction processing algorithm