How To Add Constrains For A Field in Odoo12

how to constrains the value from another field?

Hello Mates,
Please I have two fields in different modules (one is a One2many to the other) and I want to get the difference (balance) between the two fields and add a constrains if the difference (balance) is <= 0.

Hi again Bro
how to check a field is validate email format in odoo

Hi Mates! Thanks for this lesson. I am fond of your style in explaining 'how to' scenarios, by observing similar syntax, copying it, then modifying it, so I can follow it, even I am not using the same odoo version. Sometimes the syntax is different (g.e: track_visibility="always" in odoo12, tracking=True in odoo14), but by follow your 'how to' scenarios, the result is correct. :)

Module not found error: odoo.exception how to solved

Thnks👍

thank you mates for such an easy and amazing feeding of concepts. May you grow more

your code:
if rec.patient_age <= 5:
raise ValidationError(_('Age must be greater than 5.'))

while save record, in pop up error message show like this:
Error while validating constraint
name '_' is not defined


then i changed the code like this: (remove _ and () )
if rec.patient_age <= 5:
raise ValidationError('Age must be greater than 5.')

it works well.

why it is happen?
what's wrong with my code?

thank you.

thanks so much for your interesting video.
I would like to know ho to validate data on a odoo html page .


If you have any link to any video that teach ho to validate fields in a html odoo page.


thanks a lot however

can you explain me the process of adding images in the form view in odoo 13.0? Any additional component need to be downloaded

it possible to change title error 'odoo server error'?
thanks

Cool, can you also use this for IP address validation (when a field should contain a valid IP address)?