Tabular Form Validation Help

Question

Version 2.0
I have a Tabular Form that represents Show dates. There are three displayed fields: Description (Text Field), Date (Date Picker), and Active (Static Select List: Yes;1,No,0).
I need help to create a page validation to make sure that only one show is ACTIVE at a time when the row is submitted.
Thanks,
Joe

Answer 1

On the database side, I use the following technique to implement a "radiobutton" constraint. I think I picked it up from AskTom.
If you have a table like
create table t
  show_id int,
  show_date varchar2(50),
  active_flag varchar2(1),
  constraint t#pk primary key (show_id,show_date)
);which is what I think your data model looks like.
You want to ensure that for a given show, only 1 show_date is active (radiobutton-style).
Create the following function-based index on the table
create unique index i on t(decode(active_flag,'Y',show_id));This will prevent invalid data from getting into the table, no matter what.
Regarding your Apex issue, I would suggest that when you add a row to the tabular form, default the select list to Inactive. You can use client-side Javascript to do some toggling of the select lists, but that really assumes that all the rows are being shown in the tabular form. In any case, the unique index above would guarantee data integrity when the data finally hits the database.
Hope this helps.