SQL ROUND

Rounds a decimal number to a specified number of decimal places — the standard way to clean up a long, ugly fraction for display.

What & Why

ROUND(n, decimals) rounds to the given number of decimal places. Omitting the second argument rounds to the nearest whole number.

See How It Works

BUSINESS QUESTION

Marketing wants click rates rounded to two decimals and recipient estimates rounded in both directions.

id	campaign_id	sent_at	recipients	opens	clicks	unsubscribes	bounces
201	1	2024-01-20 15:00:00+00	1200	540	180	9	24
202	2	2024-02-15 16:30:00+00	800	420	96	5	12
203	3	2024-03-18 13:00:00+00	1500	610	225	14	31
204	4	2024-04-08 14:00:00+00	0	0	0	0	0

EXAMPLE QUERY

SELECT
  id AS send_id,
  ROUND(clicks::numeric / NULLIF(recipients, 0) * 100, 2) AS click_rate_pct,
  CEIL(recipients * 0.10) AS audience_ceiling,
  FLOOR(recipients * 0.10) AS audience_floor
FROM marketing.email_sends
ORDER BY send_id;

RESULT — exact output from the displayed Queryflo rows

send_id	click_rate_pct	audience_ceiling	audience_floor
201	15.00	120	120
202	12.00	80	80
203	15.00	150	150
204	NULL	0	0

ROUND, CEIL, and FLOOR operate on the displayed email-send values.

Now You Try

Practice this concept

Marketing wants click rate rounded to two decimals and ten-percent audience estimates rounded upward and downward.

Available schema

marketing

Prefix tables with marketing.table_name.

send_idclick_rate_pctaudience_ceilingaudience_floor

marketing.email_sends

Column	Type
id	integer
campaign_id	integer
sent_at	timestamp with time zone
recipients	integer
opens	integer
clicks	integer
unsubscribes	integer
bounces	integer
legacy_send_group	text

query.sql

Intermediate business practice