How to update database from multiple value textarea

I'd like to know how to create an action page that will update the database using the multiple values from a textarea field as primary keys.

thanks

 

The action page sees the textarea values as a list if comma delimited,
I would still want to enter data with carriage return.

example:

abc
xyz
lmn
tsts
...

 

glad we can help! lol

 

well I wish there was a more elegant way, the trim and replace function don't work well, so if the users don't enter the data all on one row only, it won't work.