Exam 70-761 topic 1 question 49 discussion

Actual exam question from Microsoft's 70-761

Question #: 49
Topic #: 1

Note: This question is part of a series of questions that use the same or similar answer choices. An answer choice may be correct for more than one question in the series. Each question is independent of the other questions in this series. Information and details provided in a question apply only to that question.
You have a database that contains tables named Customer_CRMSystem and Customer_HRSystem. Both tables use the following structure:
The tables include the following records:

Customer_CRMSystem -

Customer_HRSystem -

Records that contain null values for CustomerCode can be uniquely identified by CustomerName.
You need to create a list of all unique customers that appear in either table.
Which Transact-SQL statement should you run?

A.

B.

C.

D.

E.

F.

G.

H.

Show Suggested Answer

Suggested Answer: E
UNION combines the results of two or more queries into a single result set that includes all the rows that belong to all queries in the union. The UNION operation is different from using joins that combine columns from two tables.
Incorrect Answers:
F: UNION ALL incorporates all rows into the results. This includes duplicates. If not specified, duplicate rows are removed.
References:
https://msdn.microsoft.com/en-us/library/ms180026.aspx

by HaykM at Nov. 25, 2020, 1:36 p.m.