可能是因为它们无效；那些

• ; all red parts except和
• # another supplier

该怎么办？评论，也许？在Oracle中，您可以使用--或在/* ... */中加上注释。

这可能更好一些：

第一个查询：

Select S.sname 
From suppliers s 
where not exists ( (select * 
                    from parts p 
                    where p.color = 'red'
                   ) 
                    minus 
                   (select c.pid 
                    from catalog c,parts p 
                    where c.sid = s.sid 
                      and c.pid = p.pid 
                      and p.color = 'red'
                   )
                 );

第二个查询：

select p.pname 
from parts p,catalog c,suppliers s 
where p.pid = c.pid 
  and c.sid = s.sid 
  AND s.sname = 'S1'
  AND not exists (select * 
                   from catalog c1,suppliers s1 
                   where p.pid = c1.pid 
                     and c1.sid = s1.sid 
                     AND s1.sname <> 'S1'
                 );