Aug2016 cs Q20

0. Consider a database table R with attributes A and B. Which of the following SQL queries is illegal ?

Answer
Comment
Array

Option : B
Explanation :
SELECT A FROM R; legal query SELECT A, COUNT(*) FROM R; Illegal query because we can't SELECT A, COUNT(*) unless it is grouped by A. SELECT A, COUNT(*) FROM R GROUP BY A; legal query SELECT A, B, COUNT(*) FROM R GROUP BY A, B; legal query So, option (B) is correct.

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