Your database contains a table named Purchases. The table includes a DATETIME column named
PurchaseTime that stores the date and time each purchase is made. There is a non-clustered index
on the PurchaseTime column. The business team wants a report that displays the total number of
purchases made on the current day. You need to write a query that will return the correct results in
the most efficient manner. Which Transact-SQL query should you use?

A.
SELECT COUNT(*)FROM
Purchases WHERE
PurchaseTime =
CONVERT(DATE, GETDATE())

B.
SELECT COUNT(*)FROM
Purchases WHERE
PurchaseTime = GETDATE()

C.
SELECT COUNT(*)FROM
Purchases WHERE
CONVERT(VARCHAR,
PurchaseTime, 112) = CONVERT(VARCHAR, GETDATE(), 112)

D.
SELECT COUNT(*)FROM
Purchases WHERE
PurchaseTime >=
CONVERT(DATE, GETDATE()) AND PurchaseTime <
DATEADD(DAY, 1,
CONVERT(DATE,
GETDATE()))

Explanation:
http://technet.microsoft.com/en-us/libr ary/ms181034.aspx