The information system as a competitive weapon
Communications of the ACM - Special section on management of information systems
Andrew: a distributed personal computing environment
Communications of the ACM - The MIT Press scientific computation series
A snapshot differential refresh algorithm
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
Read-only transactions in a distributed database
ACM Transactions on Database Systems (TODS)
Transactions and consistency in distributed database systems
ACM Transactions on Database Systems (TODS)
Introduction to a system for distributed databases (SDD-1)
ACM Transactions on Database Systems (TODS)
Concurrency Control in Distributed Database Systems
ACM Computing Surveys (CSUR)
The notions of consistency and predicate locks in a database system
Communications of the ACM
On the design of a query processing strategy in a distributed database environment
SIGMOD '83 Proceedings of the 1983 ACM SIGMOD international conference on Management of data
Controlling large software development in a distributed environment
Controlling large software development in a distributed environment
Maintaining Consistency of Client-Cached Data
VLDB '90 Proceedings of the 16th International Conference on Very Large Data Bases
Mobile learning support with statistical inference-based cache management
ICWL'07 Proceedings of the 6th international conference on Advances in web based learning
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In an information distribution network in which records are repeatedly read, it is cost-effective to keep read-only copies in work locations. This paper presents a method of updating replicas that need not be immediately synchronized with the source data or with each other. The method allows an arbitrary mapping from source records to replica records. It is fail-safe, maximizes workstation autonomy, and is well suited to a network with slow, unreliable, and/or expensive communications links.The algorithm is a manipulation of queries, which are represented as short encodings. When a response is generated, we record which portion of the source database was used. Later, when the source data are updated, this information is used to identify obsolete replicas. For each workstation, the identity of obsolete replicas is saved until a workstation process asks for this information. This workstation process deletes each obsolete replica, and replaces it by an up-to-date version either promptly or the next time the application asks for this particular item. Throughout, queries are grouped so that the impact of each source update transaction takes effect atomically at each workstation.Optimizations of the basic algorithm are outlined. These overlap change dissemination with user service, allow the mechanism to be hidden within the data delivery subsystem, and permit very large networks.