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Paper: Dbsync: A Computer Program for maintaining duplicate database tables
Volume: 61, Astronomical Data Analysis Software and Systems III
Page: 239
Authors: Hill, N.; Gaudet, S.
Abstract: The Canadian Astronomy Data Centre(CADC) is one of the centres responsible for the distribution of HST data to the scientifc community outside the United States. One of the requirements for the external data centres is the maintenance of an accurate, up to date subset of the STScI HST archive database. The CADC was given the responsibility to develop a method for automatically maintaining a copy of the HST archive database at each of the external data centres. The HST data archive database is a SYBASE relational database which consists of nearly 200 tables in 2 databases, with a total size of approximately 550 MB. The content of many of the database tables changes on a daily basis, and the structure of the tables are subject to change. A different subset of the database is required at each of the external archive centres, and the makeup of the subsets are subject to change. The computer program "dbsync" was developed by the CADC to maintain both the content and the structure of the tables in the database. Dbsync is run at the external archive sites, accessing the source database over the Internet. Dbsync updates the content of selected tables and rebuilds any tables whose structure has changed. The external archive sites retain control over the transfer, allowing complete flexibility in the selection of data from the database. Dbsync was developed to perform a specific task, but has since evolved into general purpose tool for copying and updating tables between databases. This Paper will describe the following: an overview of the problem of maintaining a copy of the HST archive database. a description of the initial approach to a solution. a description of the dbsync program. the current uses of the dbsync program.
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