Aggregate functions perform a calculation on a set of values and return a single value.

COUNT(col)
COUNT(*)
1
2

Return the number of rows. When col is specified, the count returned will be the number of rows. When * is specified, the count returned will be the total number of rows.

AVG(col)
1

Return the average value of a given column.

SUM(col)
1

Return the sum value of a given column.

MAX(col)
1

Return the max value of a given column.

MIN(col)
1

Return the min value of a given column.