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For a field to be facet-able it must be stored in an un-tokenized field in Solr. A field will be indexed this way if it is defined as "facetable" or "stored_sortable" in DDR-Models.
Sorting
If a field will be used for sorting results then it must be configured in DDR-Models to be indexed by Solr as "sortable" or "stored_sortable."
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