Combine fields from different rows on condition

Question

Amazon offers their marketplace customers a CSV report which contains information about every article you sold. There are four rows per article, looking like this:

Answer 1

you can calculate itemprice and itemfees with two queries and join them

select a.orderid, a.price, b.fees
from (select orderid, sum(amount) price from report where amounttype='ItemPrice' group by orderid) a
     join (select orderid, sum(amount) fees from report where amounttype='ItemFees' group by orderid) b
     on a.orderid = b.orderid

this asumes there is at least one row with itemprice and one row with itemfees. otherwise you should use an outer join.