Recently, attention has been focused on temporal databases, where transaction time and valid time are added to the data. In this context, the modijcation of the schema which a DBMS can undergo during its lifetime, known as schema changes, must develop into the higher concept of schema evolution. Changes to the schema produce versions of previous schemas along both time axes and these versions must be maintained and managed during the whole database I In the Jirst part of the paper we provide a short overview on the issues of temporal relational databases and relational schema changes. In the second part we give some basic outline for the integration of these two aspects into a temporal relational database model supporting schema evolution.
A model for schema evolution in temporal relational databases
De Castro C
1993
Abstract
Recently, attention has been focused on temporal databases, where transaction time and valid time are added to the data. In this context, the modijcation of the schema which a DBMS can undergo during its lifetime, known as schema changes, must develop into the higher concept of schema evolution. Changes to the schema produce versions of previous schemas along both time axes and these versions must be maintained and managed during the whole database I In the Jirst part of the paper we provide a short overview on the issues of temporal relational databases and relational schema changes. In the second part we give some basic outline for the integration of these two aspects into a temporal relational database model supporting schema evolution.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
