Christy is right. With a reasonably small number of items, either the IN syntax or the regular expression will work.
I use the IN syntax to classify 87 counties in an app and it runs fast. A recent comparison done by Adrian Popa indicates that the regular expression syntax is faster. Here is the thread: http://lists.osgeo.org/pipermail/mapserver-users/2009-July/062071.html David. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Christy Nieman Sent: Thursday, August 13, 2009 9:01 AM To: Lars Westerlind Cc: [email protected] Subject: Re: SV: [mapserver-users] Classitems selection Hi, When you say that you could very well use expressions, do you mean regular expressions? In my experience, unless you are working with a very large data set they're fine. E.g. CLASSITEM "flavour" ... EXPRESSION /cherry|mango|lime/ Christy Lars Westerlind wrote: > > AFAIK currently I write > > CLASSITEM "flavor" > > ... > > EXPRESSION "cherry" > > Suggested extension would be to allow for > > CLASSITEM > > ... > > EXPRESSION "cherry","mango","lime" > > But really, syntax is not my concern. A could very well use > expressions, but the documentation says they are not good for > performance. And my first question is if I've missed something? > > ---------------------------------------------------------------------- > -- > > *Från:* Fawcett, David [mailto:[email protected]] > *Skickat:* 13 August 2009 15:39 > *Till:* Lars Westerlind; [email protected] > *Ämne:* RE: [mapserver-users] Classitems selection > > Do you mean something like ('[flavor]' IN ('cherry', 'mango', 'lime')? > > -----Original Message----- > *From:* [email protected] > [mailto:[email protected]] *On Behalf Of > *Lars Westerlind > *Sent:* Thursday, August 13, 2009 2:39 AM > *To:* [email protected] > *Subject:* [mapserver-users] Classitems selection > > I use the CLASSITEM - EXPRESSION with string expression rather > much, which is also recommended for performance. But sometimes I > have a few values that could be shown in the same class. Wouldn't > it be a nice idea to allow for a commaseparated set/list of > strings to match? > > ---------------------------------------------------------------------- > -- > > _______________________________________________ > mapserver-users mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/mapserver-users > _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
