Vitalii Tymchyshyn wrote:
23.03.11 12:10, Adarsh Sharma написав(ла): I just want to retrieve that id 's from page_content which do not have any entry in clause2 table.
Then
select distinct(p.crawled_page_id) from page_content p
where NOT EXISTS (select 1 from clause2 c where c.source_id = p.crawled_page_id);
is correct query.
I can't understand how
select 1 from clause2 c where c.source_id = p.crawled_page_id works too, i get my output .
What is the significance of 1 here.
Thanks , Adarsh
Best regards, Vitalii Tymchyshyn.