SQL CASE

SQL's if/then/else — lets a query make a decision for each row, and return a different value depending on the answer.

What & Why

CASE evaluates conditions from top to bottom and returns the first matching result. Here each saas.accounts.mrr value becomes a high, mid, or low reporting tier without changing the stored account row.

Branch order matters: mrr >= 200 must come before mrr >= 150, because every high-MRR account also satisfies the broader mid threshold.

See How It Works

BUSINESS QUESTION

SaaS leadership wants accounts bucketed by MRR tier.

id	name	plan	mrr	created_at	churned_at	country	employee_count	industry
1	Acme Labs	growth	240.00	2024-01-08 10:00:00+00	NULL	US	45	software
2	Northstar Co	starter	90.00	2024-02-12 09:30:00+00	2024-05-18 12:00:00+00	CA	18	services
3	Atlas Works	scale	480.00	2024-03-04 15:10:00+00	NULL	GB	120	manufacturing
4	Bright Path	growth	180.00	2024-04-19 11:45:00+00	NULL	US	62	education

EXAMPLE QUERY

SELECT
  name,
  mrr,
  CASE
    WHEN mrr >= 200 THEN 'high'
    WHEN mrr >= 150 THEN 'mid'
    ELSE 'low'
  END AS mrr_tier
FROM saas.accounts
ORDER BY id;

RESULT — exact output from the displayed Queryflo rows

name	mrr	mrr_tier
Acme Labs	240.00	high
Northstar Co	90.00	low
Atlas Works	480.00	high
Bright Path	180.00	mid

CASE classifies the four displayed saas.accounts rows in source order.

Intermediate business practice