Stock is never edited in place: a stock level is the sum of movements, each one a receipt, a sale, a transfer or an adjustment with a reason. Variants carry the SKU, the barcode and the price; the product holds what the variants share. Purchase orders bring stock in from a supplier and are received line by line.
$ npx vela create my-app --schema inventoryEvery collection, field and relation above becomes a PocketBase migration in the new project. Change any of it afterwards with vela generate migration --ai, which opens this same diagram as an editor.