Re-importing is how you update products in bulk - no duplicates.
How matching works
Rows with a SKU that already exists update the existing product (the product keeps its ID and history).
Rows without a SKU always create a new product.
Steps
Edit your CSV (change prices, add descriptions, add image URLs).
Go to Products → Import and upload the updated file.
Review the result - the report shows how many were created vs updated, plus any errors.
Tip: Always include SKUs for products you intend to update. Without a SKU, the importer can't tell it's the same product and will create a new one.
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