--- loncom/interface/lonstatistics.pm	2003/03/25 22:20:25	1.65
+++ loncom/interface/lonstatistics.pm	2003/04/21 15:12:37	1.67
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: lonstatistics.pm,v 1.65 2003/03/25 22:20:25 matthew Exp $
+# $Id: lonstatistics.pm,v 1.67 2003/04/21 15:12:37 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -51,7 +51,7 @@ Main handler for statistics and chart.
     use Apache::lonproblemstatistics;
     use Apache::lonstudentassessment;
     use Apache::lonpercentage;
-
+    use Apache::lonmysql;
 =over 4
 
 =cut
@@ -82,6 +82,7 @@ use Apache::lonproblemanalysis();
 use Apache::lonproblemstatistics();
 use Apache::lonstudentassessment();
 use Apache::lonpercentage;
+use Apache::lonmysql;
 use Time::HiRes;
 
 #######################################################
@@ -831,12 +832,17 @@ sub CreateMainMenu {
     #
     $Str .= '<table border="0"><tbody><tr>'."\n";
     $Str .= '<td></td>'."\n";
+    $Str .= '<td></td>'."\n";
     $Str .= '<td align="center"><b>Select a Report</b></td>'."\n";
     $Str .= '<td align="center"><b>Student Status</b></td></tr>'."\n";
     $Str .= '<tr>'."\n";
     #
-    $Str .= '<td align="center"><input type="submit" name="Refresh" ';
-    $Str .= 'value="Update Display" /></td>'."\n";
+    $Str .= '<td align="center">'.
+        '<input type="submit" name="Refresh" value="Update Display" />'.
+            "</td>\n";
+    $Str .= '<td align="center">'.
+        '<input type="submit" name="ClearCache" value="Clear Caches" />'.
+            "</td>\n";
     #
     $Str .= '<td align="center">';
     $Str .= '<select name="reportSelected" >'."\n";
@@ -908,6 +914,27 @@ sub handler {
     $r->print(&Apache::lonhtmlcommon::Title('Course Statistics and Charts'));
     $r->rflush();
     #
+    if (! &Apache::lonmysql::verify_sql_connection()) {
+        my $serveradmin = $r->dir_config('lonAdmEMail');
+        $r->print(<<END);
+<h2><font color="Red">Unable to connect to database!</font></h2>
+<p>
+Please notify the server administrator <b>$serveradmin</b>.
+</p><p>
+Course Statistics and Charts cannot be retrieved until the database is
+restarted.  Your data is intact but cannot be displayed at this time.
+</p>
+</body>
+</html>
+END
+        return;
+    }
+    #
+    # Clean out the caches
+    if (exists($ENV{'form.ClearCache'})) {
+        &Apache::loncoursedata::delete_caches($ENV{'requres.course.id'});
+    }
+    #
     # Set up the statistics and chart environment
     &PrepareClasslist($r);
     &PrepareCourseData($r);
@@ -919,7 +946,7 @@ sub handler {
     # Print main menu
     my %reports = ('classlist'          => 'Class list',
                    'problem_statistics' => 'Problem Statistics',
-                   'student_assessment' => 'Student Assessment',
+                   'student_assessment' => 'Problem Status Chart',
                    'percentage'         => 'Correct-problems Plot',
                    'option_response'    => 'Option Response Analysis',
 #                   'activitylog'        => 'Activity Log',