What are database schema decompositions and why do we need them?

Question

• What is database schema decomposition?
• Why do we need decompositions?

Answer 1

Probably what is meant by this is that you start with one general schema for your database and decompose this into more specific schemas.

A good choice of more specific schemas can be determined using FK constraints defined on the schema, like join dependencies etc.

Why do you need it? I believe it significantly helps with normalization and manageability.