Re: Novice needs help

Terry Lee Tucker wrote:
> I have loaded over 29,000 customer records into a database. I'm trying 
> to apply a referential foreign key that validates the country code and 
> the province code in another table. It won't work because somewhere in 
> that 29,000 records there is a province code or country code that 
> doesn't match. Is there a way to use a select statement to find out 
> which customer records has the invalid data? Here is the partial table 
> layout:
> 
> cust                                                            province
> --------                                                 -------
> country                      ===>                       country
> province                    ===>                       code
> 

If I understand correctly, something like this should work (not tested):

select c.country, c.province from cust c left join province p on 
c.country = p.country and c.province = p.code where p.country is null;

or alternatively

select c.country, c.province from cust c where not exists (select 1 from 
province p where p.country = c.country and p.code = c.province);

Joe