How records are matched
How the connector knows that this Zid product is that Odoo item.
The link is stored once
On the first successful match, the connector stores the Odoo item id on its own product record. After that it never searches again — it uses the stored id.
How the first match is made
The connector looks for a match between the SKU in Zid and the barcode or internal reference in Odoo.
An unmapped product
A product with no Odoo counterpart stays "unmapped". An order containing it will not produce a correct sales order until you map it.
Open the Products screen
Use the Unmapped Only filter to see what still needs mapping.
Customers and orders
Customers follow the same logic: the Odoo partner id is stored on the customer record. Orders store the sales order, invoice and stock picking ids.
The ids belong to one database
The stored Odoo ids are only valid in the database they came from. When moving to a different one, use Reset to clear them.