Query Join Types - Quiz Explanation

The answers you selected are indicated below, along with text that explains the correct answers.

1.	Which type of join would be used if you wanted to make sure only clients (Table 1) were displayed that had a project (Table 2) assigned to them? Please select the best answer.
	A.	Left outer join
	B.	Inner join
	C.	Right outer join
	D.	Middle outer join
	Choice B is the correct answer. Choice B is the correct answer, because the inner join displays records only when the same value for the join fields exists in both tables. Choice A, the left outer join, includes all data from Table 1 that exists in Table 2. Choice C is incorrect because a right outer join includes all data from Table 2 and only data that exists in Table 1. Choice D doesn’t even exist.

2.	Which type of query would you use to add new records to an existing table? Please select the best answer.
	A.	Make Table
	B.	Delete
	C.	Update
	D.	Append
	The correct answer is D. You would use an Append query to add records to an existing table. Choice A is incorrect because Make Table queries create a whole new table. Choice B is incorrect because Delete queries delete records. Choice C is incorrect because Update queries only update existing records.

3.	Which action query does not destroy or alter existing information? Please select the best answer.
	A.	Make Table queries
	B.	Delete queries
	C.	Append queries
	D.	Update queries
	Choice C is correct. Choice A is incorrect because a Make Table query will let you overwrite current tables. Choice B is incorrect because you could delete data accidentally. Choice C is correct because you will be adding data, and not affecting existing data. Choice D is incorrect because you could change existing data with the Update query.