Multiple row subqueries

Multiple-row subqueries in SQL return more than one row as the result and are typically used with operators like IN, ANY, ALL, or EXISTS.

Consider a table named Orders with columns OrderID, CustomerID, and OrderDate. We want to retrieve all orders made by customers from a specific city.

SELECT OrderID, OrderDate FROM Orders WHERE CustomerID IN (SELECT CustomerID FROM Customers WHERE City = 'New York');

In this example, the subquery (SELECT CustomerID FROM Customers WHERE City = 'New York') returns all CustomerIDs of customers from New York. The outer query then retrieves the OrderIDs and OrderDates of orders where the CustomerID matches any of those returned by the subquery. This query will return all orders made by customers from New York.

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