--- loncom/interface/lonsearchcat.pm	2004/04/27 15:45:04	1.218
+++ loncom/interface/lonsearchcat.pm	2004/05/03 19:24:14	1.220
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Search Catalog
 #
-# $Id: lonsearchcat.pm,v 1.218 2004/04/27 15:45:04 matthew Exp $
+# $Id: lonsearchcat.pm,v 1.220 2004/05/03 19:24:14 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -286,7 +286,7 @@ END
     $ENV{'form.phase'} = 'disp_basic' if (! exists($ENV{'form.phase'}));
     $ENV{'form.show'} = 20 if (! exists($ENV{'form.show'}));
     #
-    $ENV{'form.searchmode'} = 'basic';
+    $ENV{'form.searchmode'} = 'basic' if (! exists($ENV{'form.searchmode'}));
     if ($ENV{'form.phase'} eq 'adv_search' ||
         $ENV{'form.phase'} eq 'disp_adv') {
         $ENV{'form.searchmode'} = 'advanced';
@@ -1161,6 +1161,7 @@ sub parse_advanced_search {
 		   'lastrevisiondatestart_year','lastrevisiondateend_month',
 		   'lastrevisiondateend_day','lastrevisiondateend_year') {
 	$ENV{'form.'.$field}=~s/[^\w\/\s\(\)\=\-\"\']//g;
+        $ENV{'form.'.$field}=~s/(not\s*$|^\s*(and|or)|)//gi;
     }
     foreach ('mode','form','element') {
 	# is this required?  Hmmm.
@@ -1425,12 +1426,13 @@ sub parse_basic_search {
         &parse_domain_restrictions();
     #
     # Check to see if enough of a query is filled in
-    unless (&filled($ENV{'form.basicexp'})) {
+    my $search_string = $ENV{'form.basicexp'};
+    $search_string =~ s/(not\s*$|^\s*(and|or)|)//gi;
+    if (! &filled($search_string)) {
 	&output_blank_field_error($r,$closebutton,'phase=disp_basic');
 	return OK;
     }
     my $pretty_search_string = '<b>'.$ENV{'form.basicexp'}.'</b>';
-    my $search_string = $ENV{'form.basicexp'};
     if ($ENV{'form.related'}) {
         my @New_Words;
         ($search_string,@New_Words) = &related_version($ENV{'form.basicexp'});