查找供应每个零件的供应商的供应商编号(Find the Supplier number for those suppliers who supply every part)

查找供应每个零件的供应商的供应商编号(Find the Supplier number for those suppliers who supply every part)

我有以下表格：

Suppliers(Sno, Sname, Address) Parts(Pno, Pname, Colour) Catalogue(Sno, Pno, Price)

我想找到供应各个部分的供应商的Sno。

到目前为止，我写过：

SELECT s.sname FROM suppliers s JOIN catalogue c USING s.sno

现在我该如何编写“供应每个部件的供应商”这一部分？

我正在考虑为每个供应商Sno提供来自parts = count（pno）的count（*）。 有人可以给我一个提示/写下平等的第一部分吗？

谢谢！

I have the following tables:

Suppliers(Sno, Sname, Address) Parts(Pno, Pname, Colour) Catalogue(Sno, Pno, Price)

and I want to find the Sno of the suppliers who supply every part.

So far, I've written this:

SELECT s.sname FROM suppliers s JOIN catalogue c USING s.sno

Now how do I write the part "suppliers that supply every part"?

I was thinking about having the count(*) from parts = count(pno) for each supplier Sno. Could someone please give me a hint/write the first part of the equality?

Thanks!

最满意答案

你很亲密 您需要使用子查询添加/ by子句组：

group by s.sname having count(*) = (select count(*) from catalogue)

You're close. You need to add a group by/having clause with a subquery:

group by s.sname having count(*) = (select count(*) from catalogue)