An entity table is defined as: Maintenance contracts apply to only 10 per cent of machines. Suggest how the table could be flexed into two tables to reduce storage requirements. A first-level model...

An entity table is defined as:

Maintenance contracts apply to only 10 per cent of machines. Suggest how the table could be flexed into two tables to reduce storage requirements.

A first-level model may be altered substantially in flexing it into a second-level design. Why bother with the first-level model in the first place?