Abstract:
A relational database (RDB) schema is a
description of database requirements in terms of a set of
relations and a set of integrity constraints. An Entity-
Relationship(ER) data model is a high-level conceptual
data model that is used frequently for the conceptual
design of databases. ER data models represent a concise
description of users' data requirements without
including implementation details. Because of that, ER
data models are usually used to communicate with nontechnical
users since they are easier to understand.
Some relational database designers used the concept of
a universal relation and perform normalization to come
up with the relational database schema, without
developing an ER data model. We advocate that the
best practice for a relational database design is to start
with developing a conceptual schema like an ER data
model and then map it to a relational database schema
(as many CASE tools support). In this article, a case
tool to perform the reverse process, which is generating
an ER data model from a relational database schema, is
presented. This tool is very useful in obtaining a
conceptual schema from a relational database schema.
This tool can also be thought of as a kind of reverse
engineering case tool that aids in the reverse engineering
of legacy databases to consider new
implementation technology options.