Hi Amrit,
thanks for your help.
I know that only 5/10% of documents in the collection have more than one
value for the field I was trying to group by.
So there isn't a particular memory usage in this case. Do you know if there
is any other counter-indication I have to be aware of?
I was thinking to avoid this problem hacking the source code and deploy a
personalised version of Solr.
Best regards,
Vincenzo
On Mon, Feb 26, 2018 at 3:22 PM, Amrit Sarkar <sarkaramr...@gmail.com>
wrote:
> Vincenzo,
>
> As I read the source code; SchemaField.java
>
> /**
> * Sanity checks that the properties of this field type are plausible
> * for a field that may be used to get a FieldCacheSource, throwing
> * an appropriate exception (including the field name) if it is not.
> * FieldType subclasses can choose to call this method in their
> * getValueSource implementation
> * @see FieldType#getValueSource
> */
> public void checkFieldCacheSource() throws SolrException {
> if ( multiValued() ) {
> throw new SolrException(SolrException.ErrorCode.BAD_REQUEST,
> "can not use FieldCache on multivalued field: "
> + getName());
> }
> if (! hasDocValues() ) {
> if ( ! ( indexed() && null != this.type.getUninversionType(this) ) ) {
> throw new SolrException(SolrException.ErrorCode.BAD_REQUEST,
> "can not use FieldCache on a field w/o
> docValues unless it is indexed and supports Uninversion: "
> + getName());
> }
> }
> }
>
> Seems like FieldCache are not allowed to un-invert values for
> multi-valued fields.
>
> I can suspect the reason, multiple values will eat up more memory? Not
> sure, someone else can weigh in.
>
>
>
> Amrit Sarkar
> Search Engineer
> Lucidworks, Inc.
> 415-589-9269
> www.lucidworks.com
> Twitter http://twitter.com/lucidworks
> LinkedIn: https://www.linkedin.com/in/sarkaramrit2
> Medium: https://medium.com/@sarkaramrit2
>
> On Mon, Feb 26, 2018 at 7:37 PM, Vincenzo D'Amore <v.dam...@gmail.com>
> wrote:
>
> > Hi,
> >
> > while trying to run a group query on a multivalue field I received this
> > error:
> >
> > can not use FieldCache on multivalued field:
> >
> > <?xml version="1.0" encoding="UTF-8"?>
> > <response>
> >
> > <lst name="responseHeader">
> > <bool name="zkConnected">true</bool>
> > <int name="status">400</int>
> > <int name="QTime">4</int>
> > </lst>
> > <lst name="error">
> > <lst name="metadata">
> > <str name="error-class">org.apache.solr.common.SolrException</str>
> > <str name="root-error-class">org.apache.solr.common.
> > SolrException</str>
> > </lst>
> > <str name="msg">can not use FieldCache on multivalued field:
> > categoryLevels</str>
> > <int name="code">400</int>
> > </lst>
> > </response>
> >
> > I don't understand why this is happening.
> >
> > Do you know any way to work around this problem?
> >
> > Thanks in advance,
> > Vincenzo
> >
> > --
> > Vincenzo D'Amore
> >
>
--
Vincenzo D'Amore
