Derived Table and Aggregate Function Not Working Together

[beancounter]

I am trying to get this query using a derived table and an aggregate function to work in Excel Query:

select purordcom.*  from 
(select purOrdDet.PurAcct,
sum(PurOrdDet.ExtCost),PurOrdDet.PONbr from AEMApp.dbo.PurOrdDet PurOrdDet group by PurOrdDet.PurAcct,PurOrdDet.PONbr) as PurOrdCom

But I get a generic error. So I broke it up into two queries - one stripped of the derived table and the other stripped of the aggregate function - to try and isolate the problem:
1.

select PurOrdCom.* from  (select PurOrdDet.PurAcct,PurOrdDet.ExtCost,PurOrdDet.PONbr from AEMApp.dbo.PurOrdDet PurOrdDet) as PurOrdCom

2.

select purOrdDet.PurAcct,sum(PurOrdDet.ExtCost),PurOrdDet.PONbr from AEMApp.dbo.PurOrdDet PurOrdDet group by PurOrdDet.PurAcct,PurOrdDet.PONbr

They both worked fine. But when I combine them I get the error again.

Thank you so much!

[Rabbit]

Please use code tags when posting code.

The problem is that you can't have unaliased column definitions with in a subquery. So the solution is to give it an alias.

But my question is, why bother subquerying the aggregation if you're just going to do a select all against it? It's pointless.

[beancounter]

Rabbit,

Got your message on code tags.

Your solution worked.

The query I posted was originally part of a larger query linking this derived table to another table. When it didn't work, I stripped parts of it out to uncover the source of the error.

Thanks again. I can't tell you how frustrated I was with this!

[Rabbit]

Glad you got it working. Good luck on the rest of your project.