HLST 3341 Lecture Notes - Lecture 3: Relational Model, Database Design, Mysql
8 Dec 2018
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Lecture 3: business rules in database design (ms access) A table: person, place or thing about which we collect information or data (ex: at york, students, hospital: patient) September 22nd: entity has attributes- patient has a name, dob etc, generally tables the entities become. Degree of the relationship: only 1 entity is involved = degree is 1, example- an employee manages one or many other employees. Degree of the relationship =2: 2 entities are involved = degree is 2, example- an employee can have 0 or 1 parking spot. 1 order can have many order details. Ms access uses symbol to denote many side of the relationship. Ex: having one copy of a movie at rogers. Erd: entity relationship diagram, helps us understand the entities in our database, entities are derived from business rules, yu database- entities are course, student, classroom, teacher etc.
