As noted in [STON80], versions (also called hypothetical relations) can be used to support "what if" scenarios in the database, and offer a mechanism for manipulating live data without fear of corrupting the database. In general, versions are implemented through differential files (deltas) [SEVR76], either via forward deltas [STON81, WOOD83], or via backward deltas [KATZ82]. The main drawback of version systems is that the semantics are desired. Furthermore, no single system is general enough to subsume all of the proposals. This thesis shows that production rules in a database system can be used to implement versions, and that such rules are general and flexible enough to accommodate any new semantics that the user might want.
Title
Version Modeling Using Production Rules in the Postgres DBMS
Published
1991-06-01
Full Collection Name
Electrical Engineering & Computer Sciences Technical Reports
Other Identifiers
ERL-91-51
Type
Text
Extent
34 p
Archive
The Engineering Library
Usage Statement
Researchers may make free and open use of the UC Berkeley Library’s digitized public domain materials. However, some materials in our online collections may be protected by U.S. copyright law (Title 17, U.S.C.). Use or reproduction of materials protected by copyright beyond that allowed by fair use (Title 17, U.S.C. § 107) requires permission from the copyright owners. The use or reproduction of some materials may also be restricted by terms of University of California gift or purchase agreements, privacy and publicity rights, or trademark law. Responsibility for determining rights status and permissibility of any use or reproduction rests exclusively with the researcher. To learn more or make inquiries, please see our permissions policies (https://www.lib.berkeley.edu/about/permissions-policies).