> You need to show your work here. As your PK is a number it cannot have a > company name as a value and so this doesn't make sense.
insert into companies (company_nbr,company_name,industry,status) values (DEFAULT,'new company name','Industry','Opportunity')
With DEFAULT as the company_nbr why can't the company_name not have a value?
Because you specified company_name in the column listing for the things you are inserting values for. So in column position 2 you must have a value than can be inserted into the company_name column. It is utterly immaterial how you specified the value for column position 1.
> If you use the default when inserting the next value in the sequence is > used.
Yes, that's the theory. It didn't work for me and why it didn't is what I want to understand.
We can't help you understand if you don't show a complete working example and ask a question in relation to that example. I suggest you start from scratch, this time using scripts, so that your work is recorded and replayable.