------------------------------------쿼리---------------------------------------------
SELECT x.rn,
x.ymd,
x.ProductNo,
x.SalesAmount,
y.SalesAmount,
(x.SalesAmount - y.SalesAmount) DiffAmount
FROM ( SELECT ROW_NUMBER() OVER(PARTITION BY sb.ProductNo ORDER BY sb.ymd) rn,
sb.ymd,
sb.ProductNo,
sb.SalesAmount
FROM SalesBook sb
) AS x
JOIN (
SELECT ROW_NUMBER() OVER(PARTITION BY sb.ProductNo ORDER BY sb.ymd) rn,
sb.ymd,
sb.ProductNo,
sb.SalesAmount
FROM SalesBook sb
) AS y
ON x.rn = y.rn - 1 AND x.ProductNo = y.ProductNo
ORDER BY x.ymd, x.ProductNo
------------------------------------결과---------------------------------------------
join 뒤에 select문을 홀수나 짝수만 나오게 하려고 하는데 연산이 어디에 들어가야하는지 감이 안옵니다..
만약 제가 생각한게 잘못되었다면 조언 좀 해주시면 감사하겠습니다.
