如何在 mysql 中的 where 子句中使用别名与超前滞后函数

Question

我正在尝试将值与别名进行比较，但它说无法识别列。文档说不能在 where 子句中使用别名

WITH CTE AS
(
    SELECT
        StockCode AS TopProduct,
        COUNT(CustomerID) AS mostCustomers 
    FROM
        dbfinalweek.`e-commerce`
    GROUP BY 
        StockCode 
    ORDER BY 
        mostCustomers DESC
    LIMIT 1
)
SELECT 
    StockCode AS stock, CustomerID, 
    LEAD(StockCode, 1) OVER (ORDER BY CustomerID, InvoiceDate) AS NextItem,
    LAG(StockCode, 1) OVER () AS PreviousItem,
    InvoiceDate
FROM
    dbfinalweek.`e-commerce` AS table1 
WHERE
    (table1.StockCode = (SELECT CTE.TopProduct FROM CTE)) OR 
    (table1.NextItem = (SELECT CTE.TopProduct FROM CTE))

这是我的查询。知道如何让 Table1.NextItem 工作吗？

Answer 1

Windo功能不能直接使用，所以你必须为此制作第二个cte`

CREATE TABLE `e-commerce` (StockCode int,CustomerID int,mostCustomers int,InvoiceDate date)

with CTE AS
(
    Select 
      StockCode as TopProduct
        ,count(CustomerID) as mostCustomers 
        from `e-commerce`
      group by StockCode 
        order by mostCustomers desc  
        limit 1
),
cte2 as(
select 
     StockCode as stock 
    ,CustomerID
    , Lead(StockCode,1) over( order by CustomerID,InvoiceDate) as NextItem
    ,Lag(StockCode,1) over() as PreviousItem 
    ,InvoiceDate
from `e-commerce` )
SELECT
* FROM cte2
WHERE (stock = (Select CTE.TopProduct from CTE)) OR  (NextItem=(Select CTE.TopProduct from CTE))

stock | CustomerID | NextItem | PreviousItem | InvoiceDate
----: | ---------: | -------: | -----------: | :----------

db<>fiddle here

如何在 mysql 中的 where 子句中使用别名与超前滞后函数

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