On Thu, Apr 3, 2014 at 4:35 PM, Steve McLeod <[email protected]> wrote:
> Or can you add a 'IS_OPINION' boolean column that is populated when you > create the table or insert into the table? > > then with an index on that column you'd have extremely fast performance > with SELECT COUNT(*) FROM PUBLIC.OPINION WHERE NOT IS_OPINION > IMHO adding redundancy because of this is no good idea. A DB could be smart enough to transform SELECT COUNT(*) FROM PUBLIC.OPINION WHERE CLASSNAME NOT LIKE 'opinion%' into the difference SELECT COUNT(*) FROM PUBLIC.OPINION - SELECT COUNT(*) FROM PUBLIC.OPINION WHERE CLASSNAME LIKE 'opinion%' but the user could do it as well. I guess you may need some special handling in case the column can be NULL. -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
