Updateing A Table

[Logikos]

Okay i have a table in my database that has a few rows. There called:

Userid
Threadid
date

You can obvioulsly tell what there for.
Anyway, I added a new row called 'threadtitle' but the values are all blank. Is there anyway that i can run a update query to add all the threadtitles to the proper threadid. All the thread ids have the correct threadid, but now i want to be able to use the thread title.

Basicly, i just want to update the row threadtitle with the correct thread titles based on the threadid row. TIA!