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SQL Set Operators

SQL Set Operators   Traditional Set Operators: Union Compatibility:     Requirement for the traditional set operators.    Strong requirement.                         - Same number of columns.                         - Each corresponding column is compatible.                         - Positional correspondence.     Apply to similar tables by removing columns first. SQL UNION Example:           Example 1: Retrieve basic data about all university people.                     SELECT FacNo AS PerNo, FacFirstName                                      ...
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ER Diagram

 
ER Diagram

E-R Diagram description:

• Student: stud-Id, last-Name, first-Name, major, credits 
            – Each student has a unique id and has at most one major.

• Department: dept-Code, dept-Name, office 
            – Each department has a unique code and a unique name, and that each department has one office designated as the departmental office.

• Faculty: fact-Id, last-Name, first-Name, rank 
            – fact-Id is unique and that every faculty member must belong to department. One faculty member in each department is the chairperson.

• Class: class-Number, schedule, room – class-Number consists of dept-Code, course-Number, section.

• Textbook: isbn, author, title, publisher
             – A book can have multiple authors.

• Textbook: date, rater, rating 
            – Evaluation is a weak entity, dependent on Faculty

 


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SQL Set Operators

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