Mastering Microsoft Dynamics 365 Business Central

SetCustomerCategoryOnCustomer

Have a look at the implementation of SetLookupValueOnCustomer:

local procedure SetCustomerCategoryOnCustomer(         var Customer: record Customer;         CustomerCategoryCode: Code[10])begin    with Customer do begin        Validate(            "Customer Category Code_PKT",            CustomerCategoryCode);        Modify();    end;end;

Calling Validate is essential here. SetLookupValueOnCustomer is not just about assigning a value to the Customer Category Code_PKT field, but also about making sure it is validated against existing values in the Customer Category table. Note that the OnValidate trigger of the Customer Category Code_PKT field does not contain code.