The same customer's order shows up three times

The CRM export lists the same order three separate times. Each update just added a new row instead of replacing the old one.

BeginnerRead 4 minDoing: 20 to 30 minutes5 steps

▶ Start

What you'll have at the end

One row per customer, the most recent update kept, with the before and after row counts written down

Before you start

You need

A table or export where the same order or customer key shows up on more than one row, and every row carries a timestamp for when that version was written.

Not covered

Fixing whatever process writes a new row on every update instead of updating one in place, since that behavior may be the export's own audit design rather than a bug to remove.

Leans on

5 steps

Where to go next

Collapse duplicate signups down to one row each

for duplicate copies that disagree with each other, where picking the newest by timestamp is not enough because an older copy sometimes carries a field the newest one is missing.

Checked 26 Aug 2026

Part of the SQL for Data Analysis cookbook