If the SQL statement SELECT C1,C2,C3
FROM T4
WHERE C2 = 'Smith';
Is frequently executed,which column(s)should be considered for indexing based only on the statement itself?
A)C1 only
B)C2 only
C)C3 only
D)C1 and C2
E)C1,C2,and C3

Question

Quizplus · Accepted Answer

Since the WHERE clause filters based on the value in column C2, it is best to create an index on that column to optimize the query's performance. The other columns are not used in the filtering criteria, so indexing them would not improve the query's execution time.

If the SQL Statement SELECT C1,C2,C3