Field note · January 22, 2026

What is deliberately wrong with retail-orders

Seven thousand e-commerce order lines across four channels and six categories, with a real Q4 seasonality bump, a returns flag, and discounting that varies by channel..

1 min read ·Data quality ·quality practice

What is deliberately wrong with retail-orders.

7,000 rows, 12 columns, one row per order line. Seven thousand e-commerce order lines across four channels and six categories, with a real Q4 seasonality bump, a returns flag, and discounting that varies by channel.

Revenue is stored as well as its components, and the two agree — which makes this a good dataset for checking your own arithmetic before you trust a warehouse column. Returns are not uniformly distributed: apparel returns at roughly four times the rate of home goods, which is exactly the kind of thing an unsegmented return-rate KPI hides.

Something to try: Compute return rate by category and by channel — then by both. The SQL playground has it loaded already, and the data explorer will profile every column in one pass if you would rather look before you query.

sql
select *
from retail_orders
limit 20;

The file is generated from a fixed seed, so the CSV you download today is byte-identical to the one from last year. That matters more than it sounds: it means a lesson can say "row 412 is the interesting one" and still be right in eighteen months.

Download it, break it, keep it. CC0 — no attribution required, no account, no email.