Hi, Thanks for your reply. I did some test on my test machine. http://stage.boomi.com:8080/solr/select/?q=account:1&rows=1000. It will return resultset 384 in 3ms. If I add a new AND condition as below: http://stage.boomi.com:8080/solr/select/?q=account:1+AND+recordeddate_dt :[NOW/DAYS-7DAYS+TO+NOW]&rows=1000. It will take 18236 to return 21 resultset. If I only use the recordedate_dt condition like http://stage.boomi.com:8080/solr/select/?q=recordeddate_dt:[NOW/DAYS-7DA YS+TO+NOW]&rows=1000. It takes 20271 ms to get 412800 results. All the above URL are live, you test it.
Can anyone give me some explaination why this happens if we have the query optimization? Thank you very much. Yongjun Rong -----Original Message----- From: Walter Underwood [mailto:[EMAIL PROTECTED] Sent: Thursday, May 29, 2008 4:57 PM To: solr-user@lucene.apache.org Subject: Re: Search query optimization The people working on Lucene are pretty smart, and this sort of query optimization is a well-known trick, so I would not worry about it. A dozen years ago at Infoseek, we checked the count of matches for each term in an AND, and evaluated the smallest one first. If any of them had zero matches, we didn't evaluate any of them. I expect that Doug Cutting and the other Lucene folk know those same tricks. wunder On 5/29/08 1:50 PM, "Yongjun Rong" <[EMAIL PROTECTED]> wrote: > Hi Yonik, > Thanks for your quick reply. I'm very new to the lucene source code. > Can you give me a little more detail explaination about this. > Do you think it will save some memory if docnum = find_match("A") > > docnum = find_match("B") and put B in the front of the AND query like > "B AND A AND C"? How about sorting (sort=A,B,C&q=A AND B AND C)? Do > you think the order of conditions (A,B,C) in a query will affect the > performance of the query? > Thank you very much. > Yongjun > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Yonik > Seeley > Sent: Thursday, May 29, 2008 4:12 PM > To: solr-user@lucene.apache.org > Subject: Re: Search query optimization > > On Thu, May 29, 2008 at 4:05 PM, Yongjun Rong <[EMAIL PROTECTED]> > wrote: >> I have a question about how the lucene query parser. For example, I >> have query "A AND B AND C". Will lucene extract all documents satisfy >> condition A in memory and then filter it with condition B and C? > > No, Lucene will try and optimize this the best it can. > > It roughly goes like this.. > docnum = find_match("A") > docnum = find_first_match_after(docnum, "B") docnum = > find_first_match_after(docnum,"C") > etc... > until the same docnum is returned for "A","B", and "C". > > See ConjunctionScorer for the gritty details. > > -Yonik > > > >> or only >> the documents satisfying "A AND B AND C" will be put into memory? Is >> there any articles discuss about how to build a optimization query to >> save memory and improve performance? >> Thank you very much. >> Yongjun Rong >>
