Adding Subqueries to the SELECT Clause

Adding Subqueries to the SELECT Clause

You can add a subquery to a SELECT clause as a column expression in the SELECT list. The subquery must return a scalar (single) value for each row returned by the outer query.

Query:-

SELECT

  SalesOrderNumber,

  SubTotal,

  OrderDate,

  (

    SELECT SUM(OrderQty)

    FROM Sales.SalesOrderDetail

    WHERE SalesOrderID = 43659

  ) AS TotalQuantity

FROM

  Sales.SalesOrderHeader

WHERE

  SalesOrderID = 43659;