Importing and Exporting
Bulk changes by spreadsheet, what the columns mean, how rows are matched, and how to avoid overwriting good data.
Catalog, Products has Import CSV, Export CSV and Export Stock. A spreadsheet is the practical way to make a hundred changes, and a fast way to make a hundred mistakes.
Export First, Always
Export before you import, every time, even when you are confident.
The export is both your template, with the right column names in the right order, and your undo, because if an import goes wrong the file you exported is what you restore from. There is no undo button.
How Rows Are Matched
Rows are matched on SKU. A row whose SKU already exists updates that product. A row with a new SKU creates one.
A changed SKU creates a duplicate, it does not rename
Editing the SKU column and importing does not rename the product. It creates a second product with the new code and leaves the old one untouched. Rename a SKU in the admin, one product at a time.
A row with no SKU at all cannot be matched and will be rejected.
What the Columns Do
The export carries everything the form does: name, slug, SKU, barcode, prices, cost, weight and dimensions, stock, tracking, backorders, low stock threshold, status, type, tax class, categories, brand, tags and the product details.
Categories are given by name, separated by commas. A category that does not exist is created.
Prices are plain numbers with no currency symbol. A spreadsheet that has formatted them as currency will export text that fails to import, which is the single most common cause of a rejected file.
Stock can be imported, which is how a stocktake is applied.
An empty cell is not the same as leaving a field alone
Depending on the column, an empty cell can clear what is there. If you only want to change prices, cut the columns you are not changing out of the file rather than leaving them blank.
A Safe Routine
Export. Take a copy of the export and keep it untouched. Edit the copy. Cut it down to ten rows and import that first. Check those ten products in the admin. Then import the rest.
Ten rows takes two minutes and catches almost everything: a wrong column name, prices as text, a category that was not spelled the way you thought.
Importing Stock on Its Own
Export Stock produces a file of SKUs and quantities, which is the right shape for a stocktake. Count, fill in the numbers, import it back.
If you hold stock in several locations, read the warning in Stock and Inventory first: writing location quantities recalculates the product total, and a stock import that mixes the two ways of working will produce figures nobody can explain afterwards.
Images
Images are not part of the product import. They are uploaded on the product, or supplied by a feed where one is configured.
A large catalogue arriving without pictures is normal, and filling them in is the slow part of any migration.
Categories
Categories have their own import, which is how a large tree is built. Parents are given by name, so the file has to be ordered with parents before their children.
Exporting for Somebody Else
An export is also how you hand your catalogue to an accountant, a marketplace or a developer. It is a plain file, so check it does not contain anything you would not want to send: cost prices are in there, and they are nobody else's business.