Using SELECT with a display condition - sql-server-2005

Question

SELECT DISTINCT Invoice.InvNo, Invoice.OrderNo, Part.PartNo,
orders.orddate AS Order_Date, Invoice.InvDate AS Bill_Date,
MiscChg.Descr, MiscChg.RegFee, Invoice.InvAmt,
Orders.ClaimNo, Firm.FirmName AS Ordering_Firm,
**oppatty.attyid(WHERE oppatty.attyfor = 13)**, Location.Name1 AS Location
The bolded section is the part I'm having trouble with. I know what I have isn't right, but it demonstrates what I would like to accomplish. In the oppatty table, there could be several items listed. I want it to only display "AttyID for the entry that has an ATTYFOR = 13".
Hope this make sense, thanks
Jack

Answer 1

You need to add a CASE WHEN to the select statement.
SELECT DISTINCT
Invoice.InvNo,
Invoice.OrderNo,
Part.PartNo,
orders.orddate AS Order_Date,
Invoice.InvDate AS Bill_Date,
MiscChg.Descr,
MiscChg.RegFee,
Invoice.InvAmt,
Orders.ClaimNo,
Firm.FirmName AS Ordering_Firm,
CASE WHEN oppatty.AttyFor = 13
THEN oppatty.AttyId
ELSE '' END AS attyfor,
Location.Name1 AS Location
FROM
.........
This will display the AttyId field when the row's AttyFor field is equal to 13 and show an empty string when it's not.

Answer 2

Your query has no from or where clause and your question is a bit jumbled, but even so, I think I understand what you want to do. Assuming it's acceptable to fill the "AttyID" values with null where "AttyFor" isn't equal to 13, then you could just use a case statement. Try something like this
select
stuff.things,
case
where oppatty.attyfor <> 13 then null
else oppatty.attyid
end as attyid,
stuff.others
from
oppatty
join stuff on oppatty.ID = stuff.ID
If that's not your desired result, and you'd rather entirely exclude rows where "AttyFor" isnt equal to 13, then just use a where clause.
select
stuff.things,
oppatty.attyid,
stuff.others
from
oppatty
join stuff on oppatty.ID = stuff.ID
where
oppatty.attyfor = 13