A PRIMARY KEY constraint automatically has a UNIQUE constraint defined on it.

True

False

Question 18

A unique constraint may contain one null value.

True

False

Question 19

Bring back all employee information for employees whose regions is null.

		SELECT * FROM Employees WHERE Region Is Null
		SELECT * FROM Employees WHERE Region = Null
		SELECT * FROM Employees WHERE Region ''
		SELECT * FROM Employees WHERE Region IsNull

Question 20

I want a query that returns the first initial of the FirstName and the full LastName of employees concatenated together.

Which of the following queries does this correctly?

		SELECT Cast(FirstName,1) + ' ' + LastName FROM Employees
		SELECT LTrim(FirstName,1) + ' ' + LastName FROM Employees
		SELECT First(FirstName,1) + ' ' + LastName FROM Employees
		SELECT Left(FirstName,1) + ' ' + LastName FROM Employees

Question 21

In the Northwind database, Reports To column in the Employees table can be considered a _____.

		Primary Key
		Secondary Key
		Foreign Key
		Candidate Key

Question 22

What is the primary key of the [Order Details] table?

		There is no primary key
		Order ID and ProductID together
		OrderID only
		ProductID only

Question 23

What is wrong with the following query?

SELECT OrderID, ContactName, OrderDate, Freight

FROM Customers INNER JOIN Orders

		Nothing is wrong with this query.
		The Inner Join is not complete.
		Orders needs to be in brackets and it needs an ON statement.
		ContactName should be CustomerName.

Question 24

What kind of join is created in the the following query.

SELECT Orders.OrderID , Orders.OrderDate

, Customers.CompanyName, Orders.Freight

FROM Customers, Orders

		inner join
		left join
		cross join
		outer join

Need help ASAP pls! Fast thumbs up! TY