How to access each row value for a database item

Question

On my form I have a database datablock that represents a table in my database.
5 rows are shown with a scroll bar that can be viewed to show the rest.
The user is able to change some of the Database Item values represented in this datablock for any row shown in the datablock.
I need to validate the correctness of the users change before allowing the database datablock to update the table in the database.
But a database item in a datablock will represent a value for every row in the table. So how do I access each row value for a database item separately. What is the PL/SQL syntax?
thanks,
michelle

Answer 1

In my situation it was better to use the loop instead
of a when validate trigger because...Well it was clearly not better to use a loop that doesn't work. I don't understand what you're not clear on about the item and record validation triggers. If you have a specific validation rule for a single field (such as a date that cannot be in the future), that would go in a When-Validate-Item trigger on the date item. If the user enters a future date, your code would display an error message and raise a failure. Raising a failure prevents the item from being marked as valid. Invalid items prevent the record from being inserted/updated. Sometimes you have a validation rule that requires looking at more than one item at a time, such as two items that must either both be NULL or NOT NULL. In that case, you could not use a When-Validate-Item trigger because you can't clear or populate both at once. So then you would use a When-Validate-Record at the block level and if one field is NULL and the other isn't, you would display an error message and raise a failure. Forms is very civil in this respect; we don't throw exceptions around here, but then I digress.