(PECL solr >= 0.9.2)
SolrInputDocument::merge — Merges one input document into another
Merges one input document into another.
sourceDocThe source document.
overwrite
If this is TRUE it will replace matching fields in the destination document.
Retorna TRUE em caso de sucesso ou FALSE em caso de falha. In the future, this will be modified to return the number of fields in the new document.