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Databases and SQL: Question 9

Syllabus 9.4

Multiple choice 1 mark

Peak Trail Running Club records the results of every timed run in a single database table called RACE_TIME, shown below.

RunnerID RunnerName TrailName TimeMinutes Finished
RT01 Jonas Berg Ridge Loop 42 True
RT02 Aisha Rahman Ridge Loop 38 True
RT03 Jonas Berg Forest Trail 55 True
RT04 Priya Shah Forest Trail 47 False
RT05 Aisha Rahman Forest Trail 50 True

A club member runs this SQL statement:

SELECT MIN(TimeMinutes)
FROM RACE_TIME;

What value does this statement return?

Choose an answer to check it, then compare with the worked solution below.
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Worked solution

Step 1: Look at every value in the TimeMinutes column

SELECT MIN(TimeMinutes) FROM RACE_TIME; has no WHERE clause, so every row in the table is considered: 42, 38, 55, 47 and 50.

Step 2: Find the smallest value

Comparing all five values, 38 (RT02, Aisha Rahman on Ridge Loop) is smaller than every other value in the column.

Step 3: Confirm the match

MIN(TimeMinutes) returns the smallest value found, which is 38. (55 is the largest value, which is what MAX would return; 46.4 is the average of all five values, which is what AVG would return; and 5 is simply the number of records in the table.)

Final answer

The statement returns 38, option A.