我的 Sql（MySQL 说：#1052 - 字段列表中的列 'hswhouse.whname' 不明确

Question

create view House as 
SELECT hswhouse.whname,hsitems.description,hsitems.numInStock
from hswhouse
inner join hsitems
inner join hswhouse on hswhouse.whnum = hsitems.whouseNum
where hswhouse.whname = "San Diego"

and MySQL said:

#1052 - Column 'hswhouse.whname' in field list is ambiguous

Answer 1

You have table hswhouse twice in the query, without aliases, so it is indeed ambiguous to which of them table name hswhouse refers.

Looking at your query, one of the join s is missing a on clause (which is a syntax error in most databases apart from MySQL), and it really seems like you need table hswhouse just once. Most likely, you want:

create view House as 
SELECT h.whname, i.description, i.numInStock
from hswhouse h
inner join hsitems i on h.whnum = i.whouseNum
where h.whname = 'San Diego'