Thanks a lot Erick

Regards,
Prateek Jain

-----Original Message-----
From: Erick Erickson [mailto:erickerick...@gmail.com] 
Sent: 14 November 2016 09:14 PM
To: solr-user <solr-user@lucene.apache.org>
Subject: Re: index and data directories

Theoretically, perhaps. And it's quite true that stored data for fields marked 
stored=true are just passed through verbatim and compressed on disk while the 
data associated with indexed=true fields go through an analysis chain and are 
stored in a much different format. However these different data are simply 
stored in files with different suffixes in a segment. So you might have _0.fdx, 
_0.fdt, _0.tim, _0.tvx etc. that together form a single segment.

This is done on a per-segment basis. So certain segment files, namely the *.fdt 
and *.fdx file will contain the stored data while other extensions have the 
indexed data, see: "File naming" here for a somewhat out of date format, but 
close enough for this discussion:
https://lucene.apache.org/core/4_0_0/core/org/apache/lucene/codecs/lucene40/package-summary.html.
And there's no option to store the *.fdt and *.fdx files independently from the 
rest of the segment files.

This statement: "I mean documents which are to be indexed" really doesn't make 
sense. You send these things called Solr documents to be indexed, but they are 
just a set of fields with values handled as their definitions indicate (i.e. 
respecting stored=true|false, indexed=true false, docValues=true|false. The 
Solr document sent by SolrJ is simply thrown away after processing into segment 
files.

If you're sending semi-structured docs (say Word, PDF etc) to be indexed 
through Tika they are simply transformed into a Solr doc (set of field/value 
pairs) and the original document is thrown away as well. There's no option to 
store the original semi-structured doc either.


Best,
Erick

On Mon, Nov 14, 2016 at 12:35 PM, Prateek Jain J <prateek.j.j...@ericsson.com> 
wrote:
>
> By data, I mean documents which are to be indexed. Some fields can be 
> stored="true" but that doesn’t matter.
>
> For example: App1 creates an object (AppObj) to be indexed and sends it to 
> SOLR via solrj. Some of the attributes of this object can be declared to be 
> used for storage.
>
> Now, my understanding is data and indexes generated on data are two separate 
> things. In my particular example, all fields have stored="true" but only 
> selected fields have indexed="true". My expectation is, indexes are stored 
> separately from data because indexes can be generated by different 
> techniques/algorithms but data/documents remain unchanged. Please correct me 
> if my understanding is not correct.
>
>
> Regards,
> Prateek Jain
>
> -----Original Message-----
> From: Erick Erickson [mailto:erickerick...@gmail.com]
> Sent: 14 November 2016 07:05 PM
> To: solr-user <solr-user@lucene.apache.org>
> Subject: Re: index and data directories
>
> The question is pretty opaque. What do you mean by "data" as opposed to 
> "indexes"? Are you talking about where Lucene puts stored="true"
> fields? If not, what do you mean by "data"?
>
> If you are talking about where Lucene puts the stored="true" bits the no, 
> there's no way to segregate that our from the other files that make up a 
> segment.
>
> Best,
> Erick
>
> On Mon, Nov 14, 2016 at 7:58 AM, Prateek Jain J <prateek.j.j...@ericsson.com> 
> wrote:
>>
>> Hi Alex,
>>
>>  I am unable to get it correctly. Is it possible to store indexes and data 
>> separately?
>>
>>
>> Regards,
>> Prateek Jain
>>
>> -----Original Message-----
>> From: Alexandre Rafalovitch [mailto:arafa...@gmail.com]
>> Sent: 14 November 2016 03:53 PM
>> To: solr-user <solr-user@lucene.apache.org>
>> Subject: Re: index and data directories
>>
>> solr.xml also has a bunch of properties under the core tag:
>>
>>   <cores adminPath="/admin/cores">
>>     <core name="core0" instanceDir="core0">
>>       <property name="dataDir" value="/data/core0"/></core>
>>     <core name="core1" instanceDir="core1"/>
>>   </cores>
>>
>> You can get the Reference Guide for your specific version here:
>> http://archive.apache.org/dist/lucene/solr/ref-guide/
>>
>> Regards,
>>    Alex.
>> ----
>> Solr Example reading group is starting November 2016, join us at 
>> http://j.mp/SolrERG Newsletter and resources for Solr beginners and 
>> intermediates:
>> http://www.solr-start.com/
>>
>>
>> On 15 November 2016 at 02:37, Prateek Jain J <prateek.j.j...@ericsson.com> 
>> wrote:
>>>
>>> Hi All,
>>>
>>> We are using solr 4.8.1 and would like to know if it is possible to 
>>> store data and indexes in separate directories? I know following tag 
>>> exist in solrconfig.xml file
>>>
>>> <!-- Data Directory Used to specify an alternate directory to hold all index
>>>                                 data other than the default ./data under 
>>> the Solr home. If replication is
>>>                                 in use, this should match the replication 
>>> configuration. -->
>>>                 <dataDir>C:/del-it/solr/cm_events_nbi/data</dataDir>
>>>
>>>
>>>
>>> Regards,
>>> Prateek Jain

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