Hi,
To respond your first question: “How do I get SortedSetDocValues from index by
field name?”, DocValues.getSortedSet(LeafReader reader, String field) (which is
what you want to use to assert the existence and type of the DV) will give you
the dv instance for a single leaf reader. In general, a leaf reader is for a
specific segment, so depending on what you want to do you may need to iterate
through all the leaves (segments) if you want all values in the index (kind of
what you’ll see in NumericFacets or IntervalFacets classes).
SolrIndexSearcher.getSlowAtomicReader() will give you a view of all the
segments as a single reader, that’s why in that case the code assumes there is
only one reader that contains all the values.
Whatever you do, make sure you test your code in cases with multiple segments
(and with deletes), which is where bugs using this code are most likely to
occur.
You won’t need the UninvertingReader if you plan to index docValues, that class
is used to create a docValues-like view of a field that’s indexed=true &
docValues=false.
Related note, the DocValues API changed from 6.x to 7 (master). See LUCENE-7407.
I hope that helps,
Tomás
> On Jun 13, 2017, at 10:49 AM, SOLR4189 <klin892...@yandex.ru> wrote:
>
> How do I get SortedSetDocValues from index by field name?
>
> I try it and it works for me but I didn't understand why to use
> leaves.get(0)? What does it mean? (I saw such using in
> TestUninvertedReader.java of SOLR-6.5.1):
>
> *Map<String, UninvertingReader.Type> mapping = new HashMap<>();
> mapping.put(fieldName, UninvertingReader.Type.SORTED);
>
> SolrIndexSearcher searcher = req.getSearcher();
>
> DirectoryReader dReader = searcher.getIndexReader();
> LeafReader reader = null;
>
> if (!dReader.leaves.isEmpty()) {
> reader = dReader.leaves().get(0).reader;
> return null;
> }
>
> SortedSetDocValues sourceIndex = reader.getSortedSetDocValues(fieldName);*
>
> Maybe do I need to use SlowAtomicReader, like it:
>
> *
> UninvertingReader reader = new
> UninvertingReader(searcher.getSlowAtomicReader(), mapping)*;
>
> What is right way to get SortedSetDocValues and why?
>
>
>
> --
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> http://lucene.472066.n3.nabble.com/Solr-6-how-to-get-SortedSetDocValues-from-index-by-field-name-tp4340388.html
> Sent from the Solr - User mailing list archive at Nabble.com.
