Hello Tu Tu,

Please find below answer it may help you,

last_update field - Will update at the time when Module is updated. last_update is a helper that is not actually stored in database. It is used for concurrency check.

write_date field - Will be updated every time when you are trying to edit.

For further queries read this link https://www.odoo.com/forum/help-1/odoo-see-updated-rows-141436

Thanks & Regards,
Email: odoo@aktivsoftware.com
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