hey, i'm sorry for the confusion : our "custom query parser" is not a Lucene query parser ....
it is something we built for the client-side of Solr ... it basically transforms some search arguments into an Solr query URL example : method query( searchID, searchQuery, category, ....) returns http://solrhost/solr/select/?q=id%3AsearchString+OR+query%3AsearchString&version=2.2&start=0&rows=10&indent=on (that is what i mean by "query parsing") this method will perform a series of operations on the keywords and return a working Solr-query we are using the Java solr client and we built a framework around it to simplify our actions. example for the wildcards : we basically check if there is a keyword that starts and ends with an * (by using regular expressions) and if such a keyword is found, we add a second * at the end ... by doing this we make sure we send a working query to the Solr server we also escape special characters and other wildcards this way and we also built in highlighting for wildcard queries : if we see the user is using wildcards, we dont use the standard solr-highlighting (which doesnt work with wildcards) in stead we use regular expression to highlight the results after we get them back from the server example : *foo* in solr query becomes .*foo.* in regular expression... ( .* means a series of characters in RE) then we check if our result contains this regular expression and put some <b>-tags around the matching words and before we knew it, our wildcard searches were highlighted wether this is a good way of handling these things is open for discussion, if we have more time we might actually change the Solr-server code to fix these things. it's just a full proof work-around at this moment. grts,m "Michael Kimsal" <[EMAIL PROTECTED]> 20/04/2007 16:30 Please respond to solr-user@lucene.apache.org To solr-user@lucene.apache.org cc Subject Re: AW: Leading wildcards Maarten: Would you mind sharing your custom query parser? On 4/20/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > thanks, this worked like a charm !! > > we built a custom "QueryParser" and we integrated the *foo** in it, so > basically we can now search leading, trailing and both ... > > only crappy thing is the max Boolean clauses, but i'm going to look into > that after the weekend > > for the next release of Solr : > do not make this default, too many risks > but do make an option in the config to enable it, it's a very nice feature > > > thanks everybody for the help and have a nice weekend, > maarten > > > > > > "Burkamp, Christian" <[EMAIL PROTECTED]> > 19/04/2007 12:37 > Please respond to > solr-user@lucene.apache.org > > > To > <solr-user@lucene.apache.org> > cc > > Subject > AW: Leading wildcards > > > > > > > Hi there, > > Solr does not support leading wildcards, because it uses Lucene's standard > QueryParser class without changing the defaults. You can easily change > this by inserting the line > > parser.setAllowLeadingWildcards(true); > > in QueryParsing.java line 92. (This is after creating a QueryParser > instance in QueryParsing.parseQuery(...)) > > and it obviously means that you have to change solr's source code. It > would be nice to have an option in the schema to switch leading wildcards > on or off per field. Leading wildcards really make no sense on richly > populated fields because queries tend to result in too many clauses > exceptions most of the time. > > This works for leading wildcards. Unfortunately it does not enable > searches with leading AND trailing wildcards. (E.g. searching for "*lega*" > does not find results even if the term "elegance" is in the index. If you > put a second asterisk at the end, the term "elegance" is found. (search > for "*lega**" to get hits). > Can anybody explain this though it seems to be more of a lucene > QueryParser issue? > > -- Christian > > -----Ursprüngliche Nachricht----- > Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Gesendet: Donnerstag, 19. April 2007 08:35 > An: solr-user@lucene.apache.org > Betreff: Leading wildcards > > > hi, > > we have been trying to get the leading wildcards to work. > > we have been looking around the Solr website, the Lucene website, wiki's > and the mailing lists etc ... > but we found a lot of contradictory information. > > so we have a few question : > - is the latest version of lucene capable of handling leading wildcards ? > - is the latest version of solr capable of handling leading wildcards ? > - do we need to make adjustments to the solr source code ? > - if we need to adjust the solr source, what do we need to change ? > > thanks in advance ! > Maarten > > > -- Michael Kimsal http://webdevradio.com
