Question

i have the following sql query

SELECT
i.catalogid, i.itemname,
CASE WHEN o.oshippeddate is not null 
          AND  o.oshippeddate between @Date1 AND @Date2
    THEN ISNULL(i.F2,0)
    ELSE 0 END +
CASE WHEN o.oshippeddate2 is not null 
          AND o.oshippeddate2 between @Date1 AND @Date2
    THEN ISNULL(i.F3,0) 
    ELSE 0 END +
CASE WHEN o.oshippeddate3 is not null 
          AND  o.oshippeddate3 between @Date1 AND @Date2
     THEN ISNULL(i.F4,0) 
     ELSE 0 END AS amount, 
    amount*i.ekprice EK,
    amount * (i.unitprice
              - ((i.unitprice/((o.otax/100)+1))
              - o.odiscount-o.oshipcost-o.coupondiscount) VK
FROM orders o 
INNER JOIN oitems i 
ON i.orderid = o.orderid 

if you look at the last 2 columns that i want to select they are generated from column amount which is by it self a new column generated using the select case statements, i am new to sql and i wonder how i can get such thing to work, so basicly it says invalid column name amount

Answer 1

The column amount does not exists until the query is processed so I would sugest you a subquery and then make the multiplication

like:

SELECT AA.*,(amount*ekprice)  as EK,
        (amount*(unitprice-((unitprice/((otax/100)+1))-odiscount-oshipcost-coupondiscount)) as VK
FROM (
    SELECT
        i.catalogid,i.itemname,i.ekprice,i.unitprice,o.otax,o.odiscount,o.oshipcost,o.coupondiscount
        CASE WHEN o.oshippeddate is not null AND  o.oshippeddate  between @Date1 AND @Date2
             THEN ISNULL(i.F2,0)
             ELSE 0 END +
        CASE WHEN o.oshippeddate2 is not null AND o.oshippeddate2 between @Date1 AND @Date2
             THEN ISNULL(i.F3,0) 
             ELSE 0 END +
        CASE WHEN o.oshippeddate3 is not null AND  o.oshippeddate3 between @Date1 AND @Date2
             THEN ISNULL(i.F4,0) 
             ELSE 0 END AS amount   
    FROM 
        orders o 
        INNER JOIN oitems i ON i.orderid = o.orderid 
)AS AA

EDIT:

Just keep in mind that that kind of query with alot of CASE statments will slow the preformace significantly if alot of data is procesed so if you use this in some SERVER-CLIENT envirument I would sugest you to make the calculation on the client side before it is displayed