title: Solr Error Document is missing mandatory uniqueKey field id
body: <p>While Importing the data into Solr using DataImportHandler, I am getting the below error. Please someone provide your suggestion.</p>
  
  <pre><code>org.apache.solr.common.SolrException: Document is missing mandatory uniqueKey field: id
          at org.apache.solr.update.AddUpdateCommand.getIndexedId(AddUpdateCommand.java:92)
          at org.apache.solr.update.processor.DistributedUpdateProcessor.versionAdd(DistributedUpdateProcessor.java:717)
          at org.apache.solr.update.processor.DistributedUpdateProcessor.processAdd(DistributedUpdateProcessor.java:557)
          at org.apache.solr.update.processor.LogUpdateProcessor.processAdd(LogUpdateProcessorFactory.java:100)
          at org.apache.solr.handler.dataimport.SolrWriter.upload(SolrWriter.java:70)
          at org.apache.solr.handler.dataimport.DataImportHandler$1.upload(DataImportHandler.java:235)
          at org.apache.solr.handler.dataimport.DocBuilder.buildDocument(DocBuilder.java:512)
          at org.apache.solr.handler.dataimport.DocBuilder.buildDocument(DocBuilder.java:416)
          at org.apache.solr.handler.dataimport.DocBuilder.doFullDump(DocBuilder.java:331)
          at org.apache.solr.handler.dataimport.DocBuilder.execute(DocBuilder.java:239)
          at org.apache.solr.handler.dataimport.DataImporter.doFullImport(DataImporter.java:411)
          at org.apache.solr.handler.dataimport.DataImporter.runCmd(DataImporter.java:483)
          at org.apache.solr.handler.dataimport.DataImporter$1.run(DataImporter.java:464)
  </code></pre>