Need to reindex when changing schema.xml?

[Roger Sindreu <rs...@anpro21.com>]

Hello

I hope this question has not been asked many times. I did some research but
I never could find clearly answered anywhere.

We have several multivalue fields on a instance with millions of documents
which only contain a single value. I would like to change it to
multivalue=false to be able to use grouping and stats on those fields.

My question is: Can I do it without reindexing?

Is there any document that says when rebuilding the index is needed versus
when it is not needed?

Thanks a lot

Re: Need to reindex when changing schema.xml?

[Erick Erickson <er...@gmail.com>]

I'm going to inject a bit of caution here, since I've seen odd behaviors
pop out in cases like this. But not, I admit, this particular case.

I'd just go ahead and try it on a test index first. It's always possible
there's a safety check somewhere that'll be tripped by this kind of
change.

Erick@ParanoiaRulesSoTest

On Tue, Oct 14, 2014 at 7:02 AM, Alexandre Rafalovitch
<ar...@gmail.com> wrote:
> On 14 October 2014 04:40, Alan Woodward <al...@flax.co.uk> wrote:
>> I don't think there's any definitive reference on what requires a re-index, but that would be a nice thing to add to the Reference Guide
> +1
>
> That's a really good suggestion. Even a minimal page could be a good
> place we could add comments to as things are discovered.
>
> Personal: http://www.outerthoughts.com/ and @arafalov
> Solr resources and newsletter: http://www.solr-start.com/ and @solrstart
> Solr popularizers community: https://www.linkedin.com/groups?gid=6713853

Re: Need to reindex when changing schema.xml?

[Alexandre Rafalovitch <ar...@gmail.com>]

On 14 October 2014 04:40, Alan Woodward <al...@flax.co.uk> wrote:
> I don't think there's any definitive reference on what requires a re-index, but that would be a nice thing to add to the Reference Guide
+1

That's a really good suggestion. Even a minimal page could be a good
place we could add comments to as things are discovered.

Personal: http://www.outerthoughts.com/ and @arafalov
Solr resources and newsletter: http://www.solr-start.com/ and @solrstart
Solr popularizers community: https://www.linkedin.com/groups?gid=6713853

Re: Need to reindex when changing schema.xml?

[Alan Woodward <al...@flax.co.uk>]

You should be able to change it without re-indexing, unless you've enabled docValues on that field.  AFAIK docValues are the only persistent data structure that is different for single-valued versus multi-valued, everything else (UninvertedFields, etc) is built on the fly.

I don't think there's any definitive reference on what requires a re-index, but that would be a nice thing to add to the Reference Guide

Alan Woodward
www.flax.co.uk


On 14 Oct 2014, at 08:30, Roger Sindreu wrote:

> Hello
> 
> I hope this question has not been asked many times. I did some research but
> I never could find clearly answered anywhere.
> 
> We have several multivalue fields on a instance with millions of documents
> which only contain a single value. I would like to change it to
> multivalue=false to be able to use grouping and stats on those fields.
> 
> My question is: Can I do it without reindexing?
> 
> Is there any document that says when rebuilding the index is needed versus
> when it is not needed?
> 
> Thanks a lot