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Lecture Database management systems - Chapter 5: Relational database design by ER and EER-to-relational mapping

Chapter 5 - Relational database design by ER and EER-to-relational mapping. This chapter includes contents: Mapping of regular entity types, mapping of weak entity types, mapping of binary 1:1 relation types, mapping of binary 1:N relationship types, mapping of binary M:N relationship types, mapping of multivalued attributes, mapping of N-ary relationship types, options for mapping specialization or generalization, mapping of union types (categories). | Chapter 5 Relational Database Design by ER- and EER-to-Relational Mapping Chapter Outline ER-to-Relational Mapping Algorithm ◦ ◦ ◦ ◦ ◦ ◦ ◦ Step 1: Mapping of Regular Entity Types Step 2: Mapping of Weak Entity Types Step 3: Mapping of Binary 1:1 Relation Types Step 4: Mapping of Binary 1:N Relationship Types. Step 5: Mapping of Binary M:N Relationship Types. Step 6: Mapping of Multivalued attributes. Step 7: Mapping of N-ary Relationship Types. Mapping EER Model Constructs to Relations ◦ Step 8: Options for Mapping Specialization or Generalization. ◦ Step 9: Mapping of Union Types (Categories). Step 1: Mapping of Regular Entity Types Step 1: Mapping of Regular Entity Types. ◦ For each regular (strong) entity type E in the ER schema, create a relation R that includes all the simple attributes of E. ◦ Choose one of the key attributes of E as the primary key for R. ◦ If the chosen key of E is composite, the set of simple attributes that form it will together form the primary key of R. ER DIAGRAM FIGURE 7.2 Result of mapping the COMPANY ER schema into a .