I have a query that returns a number of tags for a set of row values. This is similar to have a set of hashtags in a twitter. And I need to add a number to each of the tags. I want the numbers to be sequential within each set of row values. So if you were selecting all the tweets for a user, you would have the username and the tweet contents and then a number of hashtags. I basically want to number the hashtags within a single tweet, starting over for the next tweet. How can I do this within an Oracle SQL query?