SELECT
MIN(buyPrice)
FROM
products;
SELECT
productCode, productName, buyPrice
FROM
products
WHERE
buyPrice = (
SELECT
MIN(buyPrice)
FROM
products);
SELECT
productline, MIN(buyprice)
FROM
products
GROUP BY productline;
SELECT
productline, productCode, productName, buyprice
FROM
products a
WHERE
buyprice = (
SELECT
MIN(buyprice)
FROM
products b
WHERE
b.productline = a.productline);
SELECT
a.productline, a.productCode, a.productName, a.buyprice
FROM
products a
LEFT JOIN
products b ON a.productline = b.productline
AND b.buyprice < a.buyprice
WHERE
b.productcode IS NULL;