As standard, Odoo does not have “uniqueness” checks on many fields. This can be problematic, for example if there are
- multiple products with the same name (which one to choose?)
- multiple customers or vendors with the same name
Either they are different, in which case they should be given different names, or someone has entered the same data twice.
It is possible to set a field as being unique in the Model definition, but it’s also possible to use Automated Actions.
How to do it
If you are not familiar with Automated Actions, start here
Enable Developer Mode and navigate to Settings / Technical / (Automation) / Automated Actions:
Click on CREATE and enter the following:
Model: Product Template
Action To Do: Execute Python Code
Trigger Condition: On Creation & Update
Before Update Domain: Internal Reference is set
Apply on: Match all records
Python Code
if record.default_code:
existing_product = env['product.template'].search([('id','!=',record.id),('default_code','=',record.default_code)])
if existing_product:
raise Warning("You can't have the same Internal Reference Number in Odoo twice!")
Odoo 14
There is a small change in the syntax:
raise UserError("You can't have the same Internal Reference Number in Odoo twice!")
Odoo tricks and tips 
Hi,
Thanks for the valued python Code, i detect one problem:
Even with internal references that don’t exist, the program its giving me the message “You can’t have the same Internal Reference Number in Odoo twice!”
Maybe the problem is solved with an extra line of code but I don’t have the knowledge for it
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I believe this technique does work, but maybe there are some special cases that need additional checking.
Is this always happening? Or only some reference numbers?
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My problem its solve, it was mine mistake, Thank you very much
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Hi,
I’ve been looking for a solution like this for quite a long time, but the Odoo support turned me down!
Thanks a lot for the tip.
I tried to create the action for contacts, but I’m really too bad at Python to achieve it…
Would you be kind enough to write the code for contacts as well ?
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This is a solution from the Odoo forum: How can I prevent users from entering duplicate Vendors? Based on NAME only
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Thanks a lot, Chris, I hadn’t found this solution yet, I’ll give it a try in the next few days.
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You may authorize only one person to enter vendor by controlling the user rights of other users. I think it will solve the issue.
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This is very helpful for me.
Duplicate Internal Reference Numbers has led to product import challenges.
Please how about HIDING THE BUTTON IN POS SALES SCREEN that allows a
cashier to serve another customer while the first in queue is not ready?
i mean a cashier to be able to serve only one customer at a time…no multiple order forms visible?
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Sorry, but that’s too technical for me (especially because POS is totally different from the rest of Odoo)
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Thanks Chris for your code it works well but I just noticed an inconvenient this code isn’t work for variants, only for products Can we do something for fix it?
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It should work if you replace Product Template with Product and product.template with product.product (in the Python)
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Thanks Chris but can we have the trigger if default code is empty also please?
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You mean that Odoo should display an error if no internal code? That can be done, but it might cause problems in various places where you can create a product “on the fly”.
Alternatively you could make it mandatory using Studio / creating an Extension View.
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I can make it mandatory using Studio already but can I raise the my own message such as “Default code is empty”
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You’d need an Automated Action with some simple Python code. If you look at the examples above under “Validation” it might help.
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sql query can use in automated actions? like update or insert?
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I don’t think so! You have to use Python.
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That’s a TERRIBLE idea, but yes, it’s possible.
It’s often a bad idea to use raw SQL, especially manipulative ones within Odoo environment, let alone you’ll be in action execution context.
Odoo has many ORM features, including but not limited to multi level caches, secure rollback systems, access control mechanisms etc. and you completely bypass them all…
Usually, it’s only required for complex QUERIES, mostly for reporting.
If you still insist on using it, you have env in execution context, it holds current cursor in env.cr
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Thank you for this valuable code, It is very helpful.
But I have a problem, I need to allow duplication but, if the name is the same it has to show the warning message. Other should be exactly as same as the previous product.
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Thanks Chris I’ll give it a try
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Thanks for so much effort Chris, I believe it’ll help many people.
Just a side note, since we won’t use any data on the record, we can just use search_count instead, it fetches the “count of records” instead of the records themselves and is faster.
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Hi,
The code works great but, I found that it is case sensative. Is there anyway to code it so that it is not case sensitive?
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Thank you very much. I made two adjustments. Internal Reference and Item Name both changed to unique
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