Shawn,
Thanks for the explanation. Very good response.
The first paragraph helped clarify what a collection is. I have read quite
about about Solr. There is so much to absorb that it is slowly sinking in.
Your 2nd paragraph definitely answered my question, i.e. passing a core
name should be ok when a collection name is specified as a method argument.
This is what I did.
Regarding the 3rd paragraph, it is good to know that Solrj is fairly robust
and should not be crashing. Nevertheless, that is what is happening. The
call to client.query() is wrapped in a try/catch sequence. Apparently no
exceptions were detected, or the program crashed before the exception could
be raised.
My next step is to check where I can report this to the Solr folks and see
if they can figure out what it is crashing. BTW, I had not checked my
output file before this morning. The output file indicates that the program
ran to completion, so I am guessing that at least one other thread is being
created and that that thread is crashing.
Regards,
Jim
On Fri, Jun 5, 2020 at 10:52 PM Shawn Heisey <apa...@elyograg.org> wrote:
> On 6/5/2020 4:24 PM, Jim Anderson wrote:
> > I am running my first solrj program and it is crashing when I call the
> > method
> >
> > client.query("coreName",queryParms)
> >
> > The API doc says the string should be a collection. I'm still not sure
> > about the difference between a collection and a core, so what I am doing
> is
> > likely illegal. Given that I have created a core, create a collection
> from
> > it so that I can truly pass a collection name to the query function?
>
> The concept of a collection comes from SolrCloud. A collection is made
> up of one or more shards. A shard is made up of one or more replicas.
> Each replica is a core. If you're not running SolrCloud, then you do
> not have collections.
>
> Wherever SolrJ docs says "collection" as a parameter for a request, it
> is likely that you can think "core" instead and have it still be
> correct. If you're running SolrCloud, you'll want to be very careful to
> know the difference.
>
> It seems very odd for a SolrJ query to cause the program to crash. It
> would be pretty common for it to throw an exception, but that's not the
> same as a crash, unless exception handling is incorrect or missing.
>
> Thanks,
> Shawn
>
