Also take a look at the documentation for the "fetch" streaming expression.
Joel Bernstein http://joelsolr.blogspot.com/ On Tue, May 2, 2017 at 2:03 PM, Joel Bernstein <joels...@gmail.com> wrote: > Yes you join more then one collection with Streaming Expressions. Here are > a few things to keep in mind. > > * You'll likely want to use the parallel function around the largest join. > You'll need to use the join keys as the partitionKeys. > * innerJoin: requires that the streams be sorted on the join keys. > * innerHashJoin: has no sorting requirement. > > So a strategy for a three collection join might look like this: > > innerHashJoin(parallel(innerJoin(bigStream, bigStream)), smallerStream) > > The largest join can be done in parallel using an innerJoin. You can then > wrap the stream coming out of the parallel function in an innerHashJoin to > join it to another stream. > > > > > > > > > > > > > > > > Joel Bernstein > http://joelsolr.blogspot.com/ > > On Mon, May 1, 2017 at 9:42 PM, Zheng Lin Edwin Yeo <edwinye...@gmail.com> > wrote: > >> Hi, >> >> Is it possible to join more than 2 collections using one of the streaming >> expressions (Eg: innerJoin)? If not, is there other ways we can do it? >> >> Currently, I may need to join 3 or 4 collections together, and to output >> selected fields from all these collections together. >> >> I'm using Solr 6.4.2. >> >> Regards, >> Edwin >> > >
