title: Missing url field using Solr DataImportHandler
body: <p>I'm new to Solr and having difficulties with the DataImportHandler. I get this message when the server starts:<br>
  Jan 27, 2010 12:27:22 PM org.apache.solr.handler.dataimport.DataImportHandler processConfiguration</p>
  
  <blockquote>
    <p>INFO: Processing configuration from solrconfig.xml: {config=dih-gensigdb-jdbc.xml}
    Jan 27, 2010 12:27:22 PM org.apache.solr.handler.dataimport.DataImporter loadDataConfig
    INFO: Data Configuration loaded successfully
    Jan 27, 2010 12:27:22 PM org.apache.solr.handler.dataimport.DataImporter verifyWithSchema
    INFO: url is a required field in SolrSchema . But not found in DataConfig  </p>
  </blockquote>
  
  <p>My dataConfig doesnt contain a url field, but i'm not sure why its required. When i use the DIH console and try to debug the config I get the following errors during document import:  </p>
  
  <blockquote>
    <p>org.apache.solr.common.SolrException: Document [null] missing required field: url</p>
  </blockquote>
  
  <p>My dataConfig looks like this:<br>
  <code>&lt;dataConfig&gt;
      &lt;dataSource name="jdbc" driver="oracle.jdbc.driver.OracleDriver"
         url="jdbc:oracle:thin:@localhost:1521:xe"
             user="genesigdb" password="genesigdb"/&gt;
      &lt;document name="PMID"&gt;
         &lt;entity name="PMID" dataSource="jdbc" query="SELECT PMID FROM PUBLICATION"&gt;
         &lt;/entity&gt;
      &lt;/document&gt;
  &lt;/dataConfig&gt;</code></p>