title: Protocols for Integrity Constraint Checking in Federated Databases creator: Grefen, P. creator: Widom, J. subject: Computer Science description: A federated database is comprised of multiple interconnected database systems that primarily operate independently but cooperate to a certain extent. Global integrity constraints can be very useful in federated databases, but the lack of global queries, global transaction mechanisms, and global concurrency control renders traditional constraint management techniques inapplicable. This paper presents a threefold contribution to integrity constraint checking in federated databases: (1) The problem of constraint checking in a federated database environment is clearly formulated. (2) A family of protocols for constraint checking is presented. (3) The differences across protocols in the family are analyzed with respect to system requirements, properties guaranteed by the protocols, and processing and communication costs. Thus, our work yields a suite of options from which a protocol can be chosen to suit the system capabilities and integrity requirements of a particular federated database environment. publisher: Stanford University date: 1994 type: Techreport type: NonPeerReviewed format: application/pdf identifier: http://ilpubs.stanford.edu:8090/57/1/1994-23.pdf identifier: Grefen, P. and Widom, J. (1994) Protocols for Integrity Constraint Checking in Federated Databases. Technical Report. Stanford University. relation: http://ilpubs.stanford.edu:8090/57/