5 - ER/EERtoRelational Mapping (LectureSession5) Chapter7...

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ER/EER to Relational  Mapping (Lecture Session-5) Chapter 7 Mon, Feb 01, 2010 1 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS
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Mon, Feb 01, 2010 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS 2 ER-to-Relational Mapping  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). Contents
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Mon, Feb 01, 2010 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS 3 The ER conceptual schema  diagram for the COMPANY  database.
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Mon, Feb 01, 2010 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS 4 ER-to-Relational Mapping 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. Example:  We create the relations EMPLOYEE,  DEPARTMENT, and PROJECT in the relational schema  corresponding to the regular entities in the ER diagram. SSN, DNUMBER, and PNUMBER are the primary keys for  the relations EMPLOYEE, DEPARTMENT, and PROJECT  as shown.
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Mon, Feb 01, 2010 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS 5
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Mon, Feb 01, 2010 DLPD, BITS-Pilani.                Prepared  by Dr.R. Gururaj, Asst.Professor of CS 6 Step 2: Mapping of Weak Entity Types For each weak entity type W in the ER schema with owner entity  simple components of composite attributes) of W as attributes of  R. Also, include as foreign key attributes of R the primary key  attribute(s) of the relation(s) that correspond to the owner entity  type(s). The primary key of R is the 
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5 - ER/EERtoRelational Mapping (LectureSession5) Chapter7...

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