Tableau Desktop Specialist — Question 113

You have two tables named EmployeeInfo and DepartmentInfo. EmployeeInfo contains four fields named Full Name, Department ID, Start Date, and Salary. DepartmenIinfo contains four fields named Department Name, Size, Department ID, and VP.

You want to combine the tables to meet the following requirements:

• Each record in EmployeeInfo must be retained in the combined table.
• The records must contain the Department Name, Size, and VP fields.
• Every record must have a full name.

Which type of join should you use?

Answer options

• A. Full outer
• B. Left
• C. Inner
• D. Union

Correct answer: B

Explanation

The correct answer is B, Left join, because it ensures that all records from the EmployeeInfo table are included, even if there is no matching record in the DepartmentInfo table. An Inner join would exclude any EmployeeInfo records without a corresponding DepartmentInfo match, while a Full outer join would include all records from both tables, which is not required here. Union is not applicable as it combines rows from two tables rather than joining them based on a key.