Tableau Desktop Specialist — Question 138

A Data Analyst has two tables named EmployeeInfo and DepartmentInfo, EmployeeInfo contains four fields named Full Name, Department ID, Start Date, and Salary.

DepartmentInfo contains four fields named Department Name, Size, Department ID, and VP. The analyst wants to combine the tables to meet the following requirements.

• EmployeeInfo is the first table that is dragged to the canvas.
• The records must contain the Full Name, and the Department Name, Size, and VP fields if available.
• Not all records have an exact match.

Which type of join should the analyst use?

Answer options

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

Correct answer: B

Explanation

The correct choice is a Left join because it allows all records from the EmployeeInfo table to be retained while including matching records from the DepartmentInfo table, filling in with NULLs where there is no match. A Full outer join would include all records from both tables, which isn't necessary here, while an Inner join would exclude non-matching records, and a Union is not applicable for combining columns from different tables.