In Odoo 16, the many2one field is used to create a relationship between two models, where one model can have many records associated with another model, but each record in the associated model can only belong to one record in the main model.

1. Relations Between
Models - many2one

2. In Odoo 16, the many2one field is used to create a relationship
between two models, where one model can have many
records associated with another model, but each record in the
associated model can only belong to one record in the main
model.
Here's an example of how to create a many2one field in Odoo
16:

3. • In the above code, we have created a many2one field named partner_id in the tip.trick model,
which will create a relationship between the tip.trick model and the res.partner model.
• The string attribute is used to specify the label for the field.
• To use this field in a view, you can add the following code to your view definition:

4. • When you create or edit a sale order record, you can select a customer from the res.partner
model using the partner_id field.
• The selected customer will be stored as a record ID in the partner_id field of the sale order
record.

5. • Note that many2one fields can also have additional attributes such as required, ondelete, and
domain, which can be used to specify whether the field is required, the behavior when the
associated record is deleted, or to filter the available records for selection, respectively.

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