There are several things to consider when designing a good database system:

Data modeling: A good database design begins with careful data modeling. This involves identifying the entities (e.g., customers, orders, products) and the relationships between them, and then creating a data model that represents these entities and relationships.

Normalization: Normalization is the process of organizing a database in such a way that it meets certain goals, such as minimizing redundancy and dependency. A properly normalized database is more efficient, flexible, and easier to maintain.

Data integrity: Data integrity refers to the accuracy, completeness, and consistency of the data in a database. It is important to design a database that ensures data integrity through the use of constraints, triggers, and other mechanisms.

Performance: A good database design should take into account the expected workload and optimize the design for good performance. This may involve the use of indexes, partitioning, and other techniques.

Security: A good database design should include measures to protect the data from unauthorized access and tampering. This may involve the use of passwords, access controls, and encryption.

Scalability: A good database design should be able to handle an increasing workload without experiencing performance degradation. This may involve the use of sharding, replication, and other techniques.

Maintainability: A good database design should be easy to maintain over time. This may involve the use of good naming conventions, documentation, and other best practices.

Overall, a good database design should balance the needs of the application with the principles of good database design in order to create a system that is efficient, flexible, and easy to maintain.