29.11.2011 12:35, Vlad Khorsun wrote: > While i agree with you about SUBSTRING, i think the much better solution > will be to allow to index COMPUTED BY columns. It allows to not compare > potentially complex expressions at optimize time and to not write exactly > same expressions in every query where such index is required.
Perhaps. And we have such a request in the tracker, AFAIR. I'm just not really sure that adding a dummy column (that could never be selected from explicitly) to improve the performance looks like a proper approach. Surely computed columns don't add any extra overhead unless you select * from the table, but this still doesn't look elegant, IMHO. But that's just me, I'm not going to object seriously. Dmitry ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
