Goal
The path to "データベース・リファクタリング"
Here is the reading path leading up to this book, derived from its dependencies and ordered from the fundamentals.
The path so far (3 books)
Why read this first: After you can make SQL 'run', the next goal is to internalize why tables are split this way and why we normalize—grounded in relational theory. This Japanese book (理論から学ぶデータベース実践入門) reconstructs Codd's relational model in practitioner's terms, giving your syntax knowledge a theoretical backbone.
Why read this first: Once you have internalized relational and normalization theory, the next stage is translating it into real table design. This Japanese book (達人に学ぶDB設計徹底指南書) concretizes theory—normalization, primary keys, foreign keys—into the practical steps of logical and physical design, bridging theory and practice. Hence it is placed as a required prerequisite.
Sources
Why read this first: Database design is not build-once-and-done; it must evolve continuously as the application changes. Ambler & Sadalage's 'Refactoring Databases' systematizes techniques for safely changing schemas, connecting initial-design knowledge to evolutionary design that keeps fixing the schema while in operation.