Design Alternatives In designing a database schema,we must ensure that we avoid two major pitfalls: Redundancy:a bad design may result in repeat information. Redundant representation of information may lead to data inconsistency among the various copies of information 。 Incompleteness:a bad design may make certain aspects of the enterprise difficult or impossible to model. Avoiding bad designs is not enough.There may be a large number of good designs from which we must choose. Database System Concepts-7th Edition 6.6 ©Silberscha乜，Korth and SudarshanDatabase System Concepts - 7 6.6 ©Silberschatz, Korth and Sudarshan th Edition Design Alternatives ▪ In designing a database schema, we must ensure that we avoid two major pitfalls: • Redundancy: a bad design may result in repeat information. ▪ Redundant representation of information may lead to data inconsistency among the various copies of information • Incompleteness: a bad design may make certain aspects of the enterprise difficult or impossible to model. ▪ Avoiding bad designs is not enough. There may be a large number of good designs from which we must choose