Modeling evolving values

The article describes a problem where updating temporal properties, like salaries, can be cumbersome.

The solution is to add an "effective period" attribute to the model, delegate the container that records associations with the effective period, and integrate the relationship with the salary.

A temporal object pattern is also presented, allowing for foolproof, easy-to-use APIs. Retroactive changes are traded off for consistent data, and alternative solutions include generic audit logs and a database ORM example.