Immediate help required with this update statement

Question

update holds set area = (select newarea from stagesteps)
where holds.stage= stagesteps.stagename and holds.step = stagesteps.STEPNAME and holds.area is not null
When I do this, it says stagesteps.stepame is an invalid name..
Any helps on this highly appreciated.. btw Advance thanx for your help.

Answer 1

update holds h
   set area = (select ss.newarea
                 from stagesteps ss
                where ss.stagename = h.stage
                  and ss.stepname = h.step)
where area is not null
   and exists (select null
                 from ss.newarea
                 from stagesteps ss
                where ss.stagename = h.stage
                  and ss.stepname = h.step);You can leave off the EXISTS clause if there will be a guaranteed matching row in stagesteps for each row in holds, or if you don't care if area is set to null if there is no match.