Using CASE and GROUP to count and separate records into groups. This example uses income.

case_and_group_for _count.sql

SELECT
(CASE
	WHEN i.income < 5000  THEN '- £5000'
	WHEN i.income BETWEEN 5000 AND 20000 THEN '£5,000 - £20,000'
	WHEN i.income BETWEEN 20000 AND 30000 THEN '£20,000 - £30,000'
	WHEN i.income BETWEEN 30000 AND 50000 THEN '£30,000 - £50,000'
	WHEN i.income > 50000  THEN '+ £5000'
	ELSE 'other'
END) AS income,
COUNT(*) AS users
FROM income_table AS i
WHERE i.income IS NOT NULL
GROUP BY income