SELECT
ROW_NUMBER() OVER (ORDER BY ProductID) AS RowNum,
ProductID,
ProductName,
UnitPrice
FROM Products
SELECT
ROW_NUMBER() OVER (PARTITION BY CategoryID ORDER BY ProductID) AS RowNum,
ProductID,
ProductName,
CategoryID
FROM Products
SELECT
*
FROM (
SELECT
ProductID,
ProductName,
CategoryID,
ROW_NUMBER() OVER (PARTITION BY CategoryID ORDER BY ProductID) AS RowNum
FROM Products
) AS RankedProducts
WHERE RowNum <= 2
SELECT
ROW_NUMBER() OVER (ORDER BY UnitPrice DESC) AS RowNum,
ProductID,
ProductName,
UnitPrice
FROM Products
亿速云「云数据库 MySQL」免部署即开即用,比自行安装部署数据库高出1倍以上的性能,双节点冗余防止单节点故障,数据自动定期备份随时恢复。点击查看>>