Hi @huuy_nguyen
Customers attributes saved in database while we click the save button in Magento admin customer section. Magento has its own events for saving customers data in database tables.
From admin customer_save_before and customer_save_after events triggered to save customers.
customer_save_before event check the validations of user form that we are submitting. customer_save_after event get the customer saving response and used to send emails after saving a customer.
I hope it will help you to understand that How save customer button work in Magento 2.
Thanks.
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Hi @huuy_nguyen ,
Customer save button calls the index controller.
module-customer/Controller/Adminhtml/Index/Index
Once index controller is executed successfully then its passes the request to Save controller which is resposible for saving all the customer data.
module-customer/Controller/Adminhtml/Index/Save
Please check these controller you will get the whole idea behind customer saving.
If you find my answer is useful for you then please Accept the solution and give Kudos.
Thanks