如何在sql中创建INNER JOIN多个表

Question

我有3个表:产品,供应商和价格.价格具有product_id和vendor_id作为外键.现在我想将价格显示为:

price_id:PRODUCT_NAME:VENDOR_NAME:价格

就像是:

SELECT p.product, v.vendor, pc.price
FROM Products AS p,
Vendors AS v
INNER JOIN Prices AS pc
ON p.product_id = pc.product_id
INNER JOIN Prices AS pc
ON v.vendor = pc.vendor_id

但我没有得到它的工作.

Answer 1

试试这个:

SELECT pr.price_id, p.product_name v.vendor_name, pr.price
FROM Prices AS pr
LEFT JOIN Products AS p ON p.product_id = pr.product_id
LEFT JOIN Vendors AS v ON v.vendor = pr.vendor_id