diff --git a/plugins/virtuoso/public/triples_management.js b/plugins/virtuoso/public/triples_management.js
index 26f986d..69f2d5e 100644
--- a/plugins/virtuoso/public/triples_management.js
+++ b/plugins/virtuoso/public/triples_management.js
@@ -1,3 +1,29 @@
+function is_valid_url(url) {
+  var pattern =/^(?:(?:https?|ftp):\/\/)(?:\S+(?::\S*)?@)?(?:(?!10(?:\.\d{1,3}){3})(?!127(?:\.\d{1,3}){3})(?!169\.254(?:\.\d{1,3}){2})(?!192\.168(?:\.\d{1,3}){2})(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\u00a1-\uffff0-9]+-?)*[a-z\u00a1-\uffff0-9]+)(?:\.(?:[a-z\u00a1-\uffff0-9]+-?)*[a-z\u00a1-\uffff0-9]+)*(?:\.(?:[a-z\u00a1-\uffff]{2,})))(?::\d{2,5})?(?:\/[^\s]*)?$/i;
+  return pattern.test(url);
+}
+
+function validate_search_form() {
+  graph_uri = jQuery("input#graph_uri");
+  query = jQuery("textarea#query");
+
+  if ( !is_valid_url(graph_uri.val())) {
+    alert( TRIPLES_MANAGEMENT_GRAPH_URI_REQUIRED_MESSAGE );
+    graph_uri.focus();
+    return false;
+  }
+
+  pattern = /.*select\s.*/i
+  if (!pattern.test(query.val())) {
+    alert( TRIPLES_MANAGEMENT_QUERY_REQUIRED_MESSAGE );
+    query.focus();
+    return false;
+  }
+
+  jQuery("#form-triples-search").submit();
+
+}
+
 function update_triple(triple_id) {
   graph = jQuery("input#graph_uri").val();
 
diff --git a/plugins/virtuoso/views/virtuoso_plugin_admin/triple_management.html.erb b/plugins/virtuoso/views/virtuoso_plugin_admin/triple_management.html.erb
index 9393ad4..f03e484 100644
--- a/plugins/virtuoso/views/virtuoso_plugin_admin/triple_management.html.erb
+++ b/plugins/virtuoso/views/virtuoso_plugin_admin/triple_management.html.erb
@@ -1,11 +1,11 @@
 <div id="virtuoso-triples-management">
   <h1><%= _('Virtuoso settings &raquo; Triples Management')%></h1>
 
-  <%= form_tag('/admin/plugin/virtuoso/triples_management', :method => 'post') do %>
+  <%= form_tag('/admin/plugin/virtuoso/triples_management', :method => 'post', :id => 'form-triples-search') do %>
     <%= labelled_form_field(_('Graph URI:'), text_field_tag(:graph_uri, @graph_uri) ) %>
     <%= labelled_form_field(_('Query SPARQL:'), text_area_tag(:query, @query, :rows => 7)) %>
     <% button_bar do %>
-      <%= submit_button(:search, _('Search triples')) %>
+      <%= submit_button(:search, _('Search triples'), :onclick => "validate_search_form(); return false;") %>
       <%= colorbox_button('add', _('Add a triple'), { :action => 'add_triple' }) %>
     <% end %>
   <% end %>
@@ -54,4 +54,9 @@
 
 </div>
 
+<script type="text/javascript">
+  TRIPLES_MANAGEMENT_GRAPH_URI_REQUIRED_MESSAGE = '<%= _('A valid GRAPH URI is required') %>';
+  TRIPLES_MANAGEMENT_QUERY_REQUIRED_MESSAGE = '<%= _('A valid QUERY is required') %>';
+</script>
+
 <%= javascript_include_tag '/plugins/virtuoso/triples_management.js' %>
--
libgit2 0.21.2