John A Meinel schrieb: > John A Meinel wrote: > >> > > Well, I was able to improve it to using appropriate index scans. > Here is the query: > > SELECT t1.id+1 as id_new FROM id_test t1 > WHERE NOT EXISTS > (SELECT t2.id FROM id_test t2 WHERE t2.id = t1.id+1) > ORDER BY t1.id LIMIT 1; > > I created a test table which has 90k randomly inserted rows. And this is > what EXPLAIN ANALYZE says: > >
As Cosimo stated the result can be wrong. The result is always wrong when the id with value 1 does not exist. -- Best Regards / Viele Grüße Sebastian Hennebrueder ---- http://www.laliluna.de Tutorials for JSP, JavaServer Faces, Struts, Hibernate and EJB Get support, education and consulting for these technologies - uncomplicated and cheap. ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
