Hi Joel, Thanks for the info.
Regards, Edwin On 3 May 2017 at 02:04, Joel Bernstein <joels...@gmail.com> wrote: > 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 > >> > > > > >
