diff --git a/search_api_solr.views.inc b/search_api_solr.views.inc
index e45df95..4da6624 100644
--- a/search_api_solr.views.inc
+++ b/search_api_solr.views.inc
@@ -5,6 +5,7 @@
  * Views integration code for the Search API Solr module.
  */
 
+use Drupal\search_api\Entity\Index;
 use Drupal\search_api\Exception\SearchApiException;
 
 /**
@@ -72,3 +73,16 @@ function _search_api_solr_views_data_alter(array &$data) {
     watchdog_exception('search_api_views', $e);
   }
 }
+
+function search_api_solr_views_data_alter(array &$data) {
+  foreach (Index::loadMultiple() as $index) {
+    // Fill in base data.
+    $key = 'search_api_index_' . $index->id();
+    $table = &$data[$key];
+    $site_hash_field = _search_api_views_find_field_alias('search_api_solr_site_hash', $table);
+    $table[$site_hash_field]['group'] = t('Search');
+    $table[$site_hash_field]['title'] = t('Site hash');
+    $table[$site_hash_field]['help'] = t('Site hash.');
+    $table[$site_hash_field]['argument']['id'] = 'search_api_argument';
+  }
+}
diff --git a/src/Plugin/search_api/backend/SearchApiSolrBackend.php b/src/Plugin/search_api/backend/SearchApiSolrBackend.php
index cb81bf5..c165910 100644
--- a/src/Plugin/search_api/backend/SearchApiSolrBackend.php
+++ b/src/Plugin/search_api/backend/SearchApiSolrBackend.php
@@ -742,6 +742,7 @@ class SearchApiSolrBackend extends BackendPluginBase implements SolrBackendInter
     $search_fields = $this->getQueryFulltextFields($query);
     // Get the index fields to be able to retrieve boosts.
     $index_fields = $index->getFields();
+    $index_fields['search_api_solr_site_hash'] = SearchApiUtility::createField($index, 'search_api_solr_site_hash', ['type' => 'string']);
     $query_fields = array();
     foreach ($search_fields as $search_field) {
       /** @var \Solarium\QueryType\Update\Query\Document\Document $document */
@@ -754,7 +755,6 @@ class SearchApiSolrBackend extends BackendPluginBase implements SolrBackendInter
     // Handle More Like This requests
     $mlt_options = $query->getOption('search_api_mlt');
     if ($mlt_options) {
-      $index_fields = $index->getFields();
       $this->getSolrHelper()->setMoreLikeThis($solarium_query, $query, $mlt_options, $index_fields, $field_names);
 
       // Override the search key by setting it to the solr document id
@@ -767,7 +767,7 @@ class SearchApiSolrBackend extends BackendPluginBase implements SolrBackendInter
     }
 
     // Set basic filters.
-    $conditions_queries = $this->createFilterQueries($query->getConditionGroup(), $field_names, $index->getFields());
+    $conditions_queries = $this->createFilterQueries($query->getConditionGroup(), $field_names, $index_fields);
     foreach ($conditions_queries as $id => $conditions_query) {
       $solarium_query->createFilterQuery('filters_' . $id)->setQuery($conditions_query);
     }
@@ -940,6 +940,7 @@ class SearchApiSolrBackend extends BackendPluginBase implements SolrBackendInter
         'search_api_id' => 'item_id',
         'search_api_relevance' => 'score',
         'search_api_random' => 'random',
+        'search_api_solr_site_hash' => 'hash',
       );
 
       // Add the names of any fields configured on the index.