It's a loop that executes for each row of the select. This is useful if you need to perform complex functions that cannot be run on a dataset.
As for how it is used in your query? I don't know. I can neither see your monitor nor read your mind. Sorry for my lack of ability :P
Hope that helps ^_^
Andy
UPDATE:
Ah, Oracle. You didn't tell me that >_<
This is not a cursor. In this case it is just a single update statement then throws an output to the entity framework letting you know if the customer was found or not
This link happens to talk about the return message AND cursors:
http://stackoverflow.com/questions/13075538/pl-sql-notfound[
^]