W03_logical-database-design_part-2.pdf - Logical Database...

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© Michael Boyle Information Systems Logical Database Design | Part 2 Database Theory and Design
© Michael Boyle Information Systems DATABASE DEVELOPMENT PROCESS ConceptualData ModelingLogicalDatabaseModelingPhysicalDatabaseModelingDatabaseImplementa9onDatabaseMaintenance
© Michael Boyle Information Systems LECTUREOUTLINE Transforming an ER Model to a Relational Model
© Michael Boyle Information Systems Steps 1.Process (Normal) Entity Types 2.Processing Weak Entity Types 3.Process (Binary) 1-to-m Relationship Types 4.Process (Binary) m-to-m Relationship Types 5.Process (Binary) 1-to-1 Relationship Types 6.Process Unary Relationship Types 7.Process n-ary Relationship Types 8.Process Supertypes/Subtypes 9.Process Multi-valued Attributes ER MODEL TO RELATIONAL MODEL | STEPS
© Michael Boyle Information Systems ER MODEL TO RELATIONAL MODEL | STEP 1 Each (Normal) Entity Type: Becomes a Relation. Includes: all Simple Attributes all Simple components of a Composite Attribute Identifier Attribute becomes Primary Key Note: Multi-valued Attributes are not processed at this step (will be processed later)
© Michael Boyle Information Systems ER MODEL TO RELATIONAL MODEL | STEP 1 EXAMPLE CustomerCustomer_NameCustomer IDCustomer_AddressPostal_CodeCityStateStreet
© Michael Boyle Information Systems ER MODEL TO RELATIONAL MODEL | STEP 2 Each Weak Entity Type: Becomes a Relation Primary Key of the Relation is composed of: Partial Key “A” of the Weak Entity Type Identifier Attribute “B” of its Identifying Owner “B” becomes a Foreign Key referencing the Relation converted from its Identifying Owner

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