COUNT

Returns the number of rows matching the query criteria.

SELECT COUNT(*) FROM MySurvey_Responses WHERE ChoiceText = 'blue'

COUNT(DISTINCT)

Returns the number of distinct, non-null field values matching the query criteria.

SELECT COUNT(DISTINCT RespondentId) AS DistinctValues FROM MySurvey_Responses WHERE ChoiceText = 'blue'

AVG

Returns the average of the column values.

SELECT ChoiceId, AVG(Size) FROM MySurvey_Responses WHERE ChoiceText = 'blue'  GROUP BY ChoiceId

MIN

Returns the minimum column value.

SELECT MIN(Size), ChoiceId FROM MySurvey_Responses WHERE ChoiceText = 'blue' GROUP BY ChoiceId

MAX

Returns the maximum column value.

SELECT ChoiceId, MAX(Size) FROM MySurvey_Responses WHERE ChoiceText = 'blue' GROUP BY ChoiceId

SUM

Returns the total sum of the column values.

SELECT SUM(Size) FROM MySurvey_Responses WHERE ChoiceText = 'blue'