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The lesson introduces the concept of mapping E/R diagrams to tables with respect to regular entities, weak entities, relationships, attributes, subtypes, and supertypes. This lesson also contains tips for logical database design and covers the various types of keys and their applications. | J Lesson 2A Logical Database Design Objectives In this lesson you will learn to 5 Map an E R Diagram to Tables in relation to the following Regular entities Attributes Relationships Weak entities Subtypes and supertypes 5 Identify keys 5 Define Specialization and Generalization 2A.1 Relational Database Design Logical Database Design Objectives In this section you will learn to Map an E R diagram to tables in relation to the following Regular entities Attributes Relationships Weak entities Subtypes and supertypes Identify keys Define Specialization and Generalization NIIT Logical Database Design Lesson 2A Slide 1 of 15 INSTRUCTOR Notes Lesson Overview The lesson introduces the concept of mapping E R diagrams to tables with respect to regular entities weak entities relationships attributes subtypes and supertypes. This lesson also contains tips for logical database design and covers the various types of keys and their applications. In addition this lesson explains specialization and generalization of entities. NUT Relational Database Design 2A.2 Logical Database Design Pre-assessment Questions 1. In an E R diagram an entity is represented as a. a. Diamond b. Line c. Box d. Oval 2. Which of the following denotes an association between entity types a. Relation b. Relationship c. Relationship type d. Relation type 3. Which data model has the database structured in fixed-format records of several types a. Relational model b. Object-based logical model c. Network model d. Hierarchical model NIIT Logical Database Design Lesson 2A Slide 2 of 15 2A.3 Relational Database .