Re: Help to simplify sample query

How about this:

select cd_area from area a1 where  not exists ((select 1,2 union select 98,45 union select 11,0) except  select
c2.cd_teacher,c2.cd_coursefrom teacher_course c2 where 
 
c2.cd_course=a1.course)

?

Tom Lane wrote:

>Daniel Henrique Alves Lima <email_daniel_h@yahoo.com.br> writes:
>  
>
>>    I don't think this is possible, but: Is there a efficient way to 
>>compare if the result of a query is a superset of the result of another ?
>>    
>>
>
>Perhaps do "SELECT foo EXCEPT SELECT bar" and see if you get anything?
>
>            regards, tom lane
>
>  
>