Best Day for Each Campaign

For each campaign, find the day with the most clicks. If several days tie, return the earliest of them.

Expected output

name, day, clicks. Sorted by name.

Row order is checked. Column names are not checked; numbers are compared to 2 decimals.

Dataset: Digital ads performance

A retailer's paid campaigns across search, social, display and video in February 2026: daily delivery, individual ad clicks and purchases.

campaigns

One row per campaign.

campaign_id	INTEGER	primary key
name	TEXT
channel	TEXT	search, social, display or video
start_date	TEXT	YYYY-MM-DD
end_date	TEXT	YYYY-MM-DD inclusive, NULL if still running
daily_budget	REAL	USD

ad_daily

Delivery per campaign per day it ran, as reported by the ad platform. clicks is the platform's count, which may differ from our own click log.

ad_clicks

Our own click log: one row per ad click that reached the site and was tracked.

click_id	INTEGER	primary key, increases with clicked_at
campaign_id	INTEGER
user_id	INTEGER
clicked_at	TEXT	YYYY-MM-DD HH:MM:SS (UTC)

conversions

One row per purchase. Some purchases come from users who never clicked an ad.

Engine: SQLite. Dates are text (YYYY-MM-DD); use strftime(), date() and julianday() for date math.