Normalización de Bases de Datos

Instrucciones:

• Descarga el pdf donde encontrarás una tabla de datos sin normalizar
• Normaliza la tabla (se recomienda el uso de Google Sheets)
• Realiza un diagrama ER de Chen
• Realiza un diagrama de tipo patas de gallo
• Crea un repositorio con el Readme
• Inserta en el Readme la descripción del ejercicio así como los diagramas creados.

Normalización paso a paso

1NF

• Quitar grupos repetidos de cursos ( course1, course2, course3)

• Separar entidades: students, classroom, course. Los cursos no dependen del estudiante, sino del aula.

  • STUDENT (id_student PK, name_student, classroom)
  • CLASSROOM (id_classroom PK, classroom_description)
  • COURSE (id_course PK, course_name)

2NF

• Los cursos dependen del aula, no del estudiante, por tanto no se relacionan Student con Course.

  • STUDENT (id_student PK, name_student, classroom FK→CLASSROOM)
  • CLASSROOM (id_classroom PK, classroom_description)
  • COURSE (id_course PK, course_name)
  • CLASSROOM_COURSE (id_classroom FK, id_course FK)

3NF

• STUDENT (id_student PK, name_student, classroom FK→CLASSROOM)
• CLASROOM (id_classroom PK, classroom_description)
• COURSE (id_course PK, course_name)
• CLASSROOM_COURSE (id_classroom FK, id_course FK)

Diagrama ER de Chen

erDiagram
    STUDENT }o--|| CLASSROOM : "belongs to"
    CLASSROOM ||--|{ CLASSROOM_COURSE : "contains"
    COURSE ||--|{ CLASSROOM_COURSE : "belongs to"

    STUDENT {
        int id_student PK "ID Student"
        string name_student "Name"
        string id_classroom FK "ID Classroom"
    }
    CLASSROOM {
        string id_classroom PK "ID Classroom"
        string classroom_description "Description"
    }
    COURSE {
        int id_course PK "ID Course"
        string course_name "Course name"
    }
    CLASSROOM_COURSE {
        string classroom FK
        int id_course FK
    }

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Diagrama UML

classDiagram
    class Student {
        +int id_student
        +String name_student
        +String id_classroom
    }
    class Classroom {
        +String id_classroom
        +String classroom_description
    }
    class Course {
        +int id_course
        +String course_name
    }
    class Classroom_Course {
        +String id_classroom
        +int id_course
    }

    Student "*" -- "1" Classroom : belongs to
    Classroom "1" -- "*" Classroom_Course : contains
    Course "1" -- "*" Classroom_Course : belongs to

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