Maintain Data Integrity When Merging Amazon Ads Exports

Verify column names and formats before merging

Amazon Ads exports can change column order or naming between date ranges, report types, or marketplace views. Before combining files, compare the header row in each CSV. Standardize names such as Campaign ID, Ad Group ID, Impressions, and Sales. Check that date fields are real dates, not text, and that currency or decimal separators use one consistent format.

A quick Power Query import can help because it reads each file with the same transformation steps and alerts you when columns are missing or renamed. If you regularly combine exports, a tool like Amazon Ads Dashboard by Todoza can consolidate reports before they reach Excel, reducing manual header mismatches.

Use backups and consistent row keys

Keep at least one untouched copy of each raw export before you sort, delete, or combine. A duplicate row created by overlapping reports is easier to find when the raw files still exist. The safest merges rely on a consistent key rather than row position. Use Campaign ID plus a date or keyword identifier so every row can be traced back to its source.

• Store raw exports in a separate folder or sheet before editing.
• Use a composite key such as campaign ID + date + keyword ID when one column alone is not unique.
• Remove duplicates only after confirming the key matches across all files.

When this matters

Strict integrity matters when small errors change campaign decisions: pausing a keyword based on slightly inflated spend, comparing performance across accounts, or merging daily exports into a monthly view. In these cases, a single shifted column or duplicated row can make an underperforming ad look profitable or hide waste.

Following a short verification and backup routine is usually faster than troubleshooting a corrupted workbook later.