The point is sometimes data after de-normalization will be huge, in some case, it's even impossible. Thanks, -----Original Message----- From: Lee Carroll [mailto:lee.a.carr...@googlemail.com] Sent: Wednesday, June 27, 2012 7:38 PM To: solr-user@lucene.apache.org Subject: Re: how Solr/Lucene can support standard join operation
In your example de-normalising would be fine in a vast number of use-cases. multi value fields are fine. If you really want to, see http://wiki.apache.org/solr/Join but make sure you loose the default relational dba world view first and only go down that route if you need to. On 27 June 2012 12:27, Robert Yu <robert...@morningstar.com> wrote: > The ability of join operation supported as what > http://wiki.apache.org/solr/Join says is so limited. > I'm thinking how to support standard join operation in Solr/Lucene because > not all can be de-normalized efficiently. > > Take 2 schemas below as an example: > > (1) Student > sid > name > cid // class id > > (2) class > > cid > > name > > major > In SQL, it will be easy to get all students' name and its class name where > student's name start with 'p' and class's major is "CS". > Select s.name, c.name from student s, class c where s.name like 'p%' > and c.major = "CS". > > How Solr/Lucene support the above query? It seems they do not. > > Thanks, > ________________________________ > Robert Yu > Application Service - Backend > Morningstar Shenzhen Ltd. > Morningstar. Illuminating investing worldwide. > > +86 755 3311-0223 voice > +86 137-2377-0925 mobile > +86 755 0000-0000 fax > robert...@morningstar.com<mailto:robert...@morningstar.com> > 8FL, Tower A, Donghai International Center ( or East Pacific > International Center) > 7888 Shennan Road, Futian district, > Shenzhen, Guangdong province, China 518040 > > http://cn.morningstar.com<http://cn.morningstar.com/> > > This e-mail contains privileged and confidential information and is intended > only for the use of the person(s) named above. Any dissemination, > distribution, or duplication of this communication without prior written > consent from Morningstar is strictly prohibited. If you have received this > message in error, please contact the sender immediately and delete the > materials from any computer. >
