SUMPRODUCT to SQL SUM of products

Most workplace SUMPRODUCTs are SUMIFS in a trench coat. The honest ones multiply two columns.

SELECT SUM(CASE WHEN status = 'Shipped' THEN total_amount ELSE 0 END)
FROM Orders;

-- actual product of two columns
SELECT SUM(qty * unit_price) FROM OrderLines;

Do not multiply whole columns in SQL. That is a CROSS JOIN of the sheet against itself.

Canonical translation

SELECT SUM(CASE WHEN status = 'Shipped' THEN total_amount ELSE 0 END)
FROM Orders;

-- actual product of two columns
SELECT SUM(qty * unit_price) FROM OrderLines;