(2) * Group By and Having clause are working together in terms of Group by must take on of the select statement attributes but Having clause can't take same one because it isn't aggregated Group by can take aggregated attributed where no need to use Having clause Group by can perform correctly without any assistance from where statement but it must have Having clause None O (2) * Exist construct can be useful between two or more subqueries to check It returns true if the inner subquery test empty output Returns true if the inner subquery find a match with outer query Returns true if the subquery has resulted data and it is not empty None O Unique construct usually used to check if there are Matched tuples Similar attributes All of the above are correct None