I am using CDH 15.5, which comes with Solr 4.10   I ran into issues indexing a csv document, in the schema config i had specified a uniqueKey value, for some reason it kept giving me a "org.apache.solr.common.SolrException: Document contains multiple values for uniqueKey field: id" -- I've asked about this in a separate thread. So i removed the uniqueKey constraint in the configurations, then i ran into another error -- "QueryElevationComponent requires the schema to have a uniqueKeyField" , this means uniqueKey definition is enforced in the solrconfig.xml file. I subsequently disabled this from the Solrconfig.xml, and was able to successfully index the file.   However when i try to query from the Solr admin using the Select handler, i get an exception below. A quick glance through the stacktrace shows that the null exception is returned in the createMainQuery method.   https://github.com/apache/lucene-solr/blob/master/solr/core/src/java/org/apache/solr/handler/component/QueryComponent.java   String keyFieldName = rb.req.getSchema().getUniqueKeyField().getName();   In the method definition of CreateMainQuery, there's an attemp to assign a certain variable the uniqueKeyField, which if not enabled means its null, hence the null exception.       StackTrace:   java.lang.NullPointerException at org.apache.solr.handler.component.QueryComponent.createMainQuery(QueryComponent.java:800) at org.apache.solr.handler.component.QueryComponent.regularDistributedProcess(QueryComponent.java:679) at org.apache.solr.handler.component.QueryComponent.distributedProcess(QueryComponent.java:632) at org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:255) at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:135) at org.apache.solr.core.SolrCore.execute(SolrCore.java:2259) at org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:923) at org.apache.solr.servlet.SolrDispatchFilter.httpSolrCall(SolrDispatchFilter.java:484) at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:260) at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:254) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.solr.servlet.SolrHadoopAuthenticationFilter$2.doFilter(SolrHadoopAuthenticationFilter.java:408) at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:631) at org.apache.hadoop.security.token.delegation.web.DelegationTokenAuthenticationFilter.doFilter(DelegationTokenAuthenticationFilter.java:301) at org.apache.hadoop.security.authentication.server.AuthenticationFilter.doFilter(AuthenticationFilter.java:579) at org.apache.solr.servlet.SolrHadoopAuthenticationFilter.doFilter(SolrHadoopAuthenticationFilter.java:413) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:610) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:503) at java.lang.Thread.run(Thread.java:745) Can anyone confirm they've ran into this issue with CDH 15.5           ... View more