: I remember the same, except I think I've seen the recommendation that you : make all the letters lower-case. As I remember, there are some interesting : edge cases that you might run into later with upper case.
i can't think of *any* reason why upper case character names i na field would cause you problems. In general, the low level guts of SOlr don't care what characters you use i na field name. where people run into problems is that some specific features of solr either have limitiations in what they can deal with in a field name, or work in some wya that makes certain characters extremely frustrating to use. the simplest example of frustration is in needing to URL escape any special characters when building a URL that contains a field name (ie: as the value of a facet.field param for example) an example of a hard limitation is sorting: the sort param expects whitespace seperated lists of "<fieldname> <asc|desc>" pairs -- if your field name contains whitespace, that can screw you up. the lucene QueryParser is another situation where punctuation and whitespace are significant, so having those characters in your field names may cause your problems (i think in most cases they can be backslash escaped, but i'm not certain) As far as the specific question about "." in field names -- i can't think of any feature that would break on that ... the only thing that comes to mind as a possibility is using per-field override params (ie: if the field name is "foo.bar" and you want to use facet.field=foo.bar&f.foo.bar.facet.prefix=xxx) ... but even then, i'm pretty sure it would work fine (you and the other people maintaining your code might get really confused however) -Hoss