Sorting on numbers vs. letters

[tedxas]

I have three MySQL columns for recording dates: startdate,follupdate,enddate.

Currently, I sort on the folloupdate column as so:

SELECT * FROM projects ORDER BY followupdate

Once a project is completed, the followupdate column is emptied and the enddate column is populated. As a result, my "empty" records appear in the list ahead of my numerical, populated entries in the followupdate column.

SO, how can I sort on the followupdate column so that the most recent date shows up first and all the completed (empty) items show up at the end?

Thanks in advance!

Ted

[Anon]

I didn't test this, but you can use a CASE statement to return a value:

SELECT * FROM projects
ORDER BY
case
when followupdate is null then enddate
else followupdate
end