Is it necessary to read functions and procedures in a database to understand the system's logic?

Yes, it is often necessary to read functions and procedures in the database to fully understand the business logic of the system. In large or legacy systems, part of the logic may be implemented directly at the DBMS level — for example, in the form of stored procedures, triggers, or functions. This helps to understand how data is processed, what rules are applied, and how different parts of the system interact. It is especially important when analyzing complex processes, migration, or refactoring.