如果使用offset fetch next，则select中的子查询仅执行5次rec

Question

这是一个虚拟查询，我想知道，md col查询（相关子查询）将仅执行5条记录或sales.customer表的所有记录。

    SELECT CustomerID, 
(SELECT TOP 1 Sales.SalesTerritory.ModifiedDate
FROM Sales.SalesTerritory 
WHERE Sales.SalesTerritory.TerritoryID = Sales.Customer.TerritoryID) md
FROM Sales.Customer 
ORDER BY CustomerID OFFSET 10 ROWS FETCH NEXT 5 ROWS ONLY

你真诚的

Answer 1

都不是。它执行了15次。

(5 row(s) affected)
Table 'SalesTerritory'. Scan count 0, logical reads 30, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'Customer'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

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