. In Section 15.2 we provide an overview of the methodology and briefly describe the main activities associated with each design phase. In Section 15.3 we focus on the methodology for conceptual database design and present a detailed description of the steps required to build a conceptual data model. We use the Entity– Relationship (ER) modeling technique described in Chapters 11 and 12 to create the conceptual data model. In Chapter 16 we focus on the methodology for logical database design for the relational model and present a detailed description of the steps required to convert a conceptual data model into a logical data model. This chapter also includes an optional step that describes how to merge two or more logical data models into a single logical data model for those using the view integration approach (see Section 9.5) to manage the design of a database with multiple user views. In Chapters 17 and 18 we complete the database design methodology by presenting a detailed description of the steps associated with the production of the physical database design for relational DBMSs. This part of the methodology illustrates that the develop- ment of the logical data model alone is insufficient to guarantee the optimum implementa- tion of a database system. For example, we may have to consider modifying the logical model to achieve acceptable levels of performance. Appendix G presents a summary of the database design methodology for those readers who are already familiar with database design and simply require an overview of the main steps. Throughout the methodology the terms ‘entity’ and ‘relationship’ are used in place of ‘entity type’ and ‘relationship type’ where the meaning is obvious; ‘type’ is generally only added to avoid ambiguity. In this chapter we mostly use examples from the Staff user views of the DreamHome case study documented in Section 10.4 and Appendix A.