-- Count number of rows

SELECT COUNT(*)

FROM table_name;

-- Count with condition

SELECT COUNT(*)

FROM table_name

WHERE column_name = 'value';

-- Sum a column

SELECT SUM(column_name)

FROM table_name;

-- Combine SUM and COUNT

SELECT COUNT(*), SUM(column_name)

FROM table_name;

-- Group results

SELECT column_name, COUNT(*), SUM(other_column)

FROM table_name

GROUP BY column_name;