Exam 70-767 topic 1 question 98 discussion

Union all or Union is wrong as they are two different structures - Merge is out too as it is not a Ssis Component - Hence its Merge Join as nothing is mentioned about being sorted or unsorted.

Merge Join, due to the 2 data sources: " Merge Join is same as JOIN in t-sql, you can choose between different types of Inner join, left outer join and outer join the difference is that with Merge join transformation you can support two inputs from two different data source, for example one from flat file and another from oracle DB, but with join in t-sql you can only join from one data source." https://stackoverflow.com/questions/46664399/ssis-difference-between-merge-and-merge-join

It is a Merge Join, here is the detailed example - https://www.red-gate.com/simple-talk/sql/ssis/ssis-basics-using-the-merge-join-transformation/

Use can't use Merge or Union when you have Data with different structures. Columns structure needs to align. I guess Merge Join still works

From the options we can judge between Union All, Merge and Merge Join. ..."The Merge transformation is similar to the Union All transformations. Use the Union All transformation instead of the Merge transformation in the following situations: The transformation inputs are not sorted. The combined output does not need to be sorted. The transformation has more than two inputs."... link: https://simplebiinsights.com/ssis-difference-between-merge-and-merge-join/#:~:text=Merge%20Join%20transformation%20merge%20the,or%20LEFT%20or%20INNER%20JOIN.&text=Merge%20Join%20Transformation%20requires%20sorted,joined%20columns%20have%20matching%20metadata. We don't know if our inputs are sorted but we know that we have two different structured sources and in this situation we cannot use Union All, so the best answer is to use Merge or Merge Join. I would choose Merge since it is more similar to Union All and also in its definition: "Merge data from two data sources, such as tables and files", which is our case. So, answer: F

C. Union All The Union All transformation combines multiple inputs into one output. For example, the outputs from five different Flat File sources can be inputs to the Union All transformation and combined into one output. https://docs.microsoft.com/en-us/sql/integration-services/data-flow/transformations/union-all-transformation?view=sql-server-ver15