Which of the following statements are true about an SQL query? P. An SQL query can contain HAVING clause even if it does not have a GROUP BY clause Q. An SQL query can contain HAVING clause only if it does not have a GROUP BY clause R. All attributes used in the GROUP BY clause must appear in the SELECT clause S. Not all attributes used in the GROUP BY clause need to appear in the SELECT clause

Which of the following statements are true about an SQL query? P. An S

1.	Which of the following statements are true about an SQL query? P. An SQL query can contain HAVING clause even if it does not have a GROUP BY clause Q. An SQL query can contain HAVING clause only if it does not have a GROUP BY clause R. All attributes used in the GROUP BY clause must appear in the SELECT clause S. Not all attributes used in the GROUP BY clause need to appear in the SELECT clause
A.	P and R
B.	P and S
C.	Q and R
D.	Q and S
Answer» D. Q and S

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Which of the following statements are true about an SQL query? P. An SQL query can contain HAVING clause even if it does not have a GROUP BY clause Q. An SQL query can contain HAVING clause only if it does not have a GROUP BY clause R. All attributes used in the GROUP BY clause must appear in the SELECT clause S. Not all attributes used in the GROUP BY clause need to appear in the SELECT clause
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