Question

Table has columns for issue_date, part_num and date_received.

If an issue_date is null, I want to select issue_date of part_num + 1 (the next part number), and insert it in the issue_date column of the part with no issue date.

part_num is sequential.

What sql statement would select then insert the appropriate issue date?

Thank you in advance for any help.

Figured it out with a little self join statement.. thank you delete if you wish!!

Answer 1

Try this:

update t
set t.issue_date = (select issue_date 
                       from t t1 
                      where t1.part_num = t.part_num+1)
where t.issue_date is null

But, if the next part number also doesn’t have issue_date, this will ramain null’s in issue_date. To solve this problem you can change query to this one (if it’s suitable for your application):

update t
set t.issue_date = (select min(issue_date)
                       from t t1 
                      where t1.part_num > t.part_num)
where t.issue_date is null