--- loncom/interface/lonmysql.pm	2005/02/09 21:21:08	1.26
+++ loncom/interface/lonmysql.pm	2009/02/01 22:03:42	1.38
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # MySQL utility functions
 #
-# $Id: lonmysql.pm,v 1.26 2005/02/09 21:21:08 matthew Exp $
+# $Id: lonmysql.pm,v 1.38 2009/02/01 22:03:42 lueken Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -32,14 +32,23 @@ package Apache::lonmysql;
 use strict;
 use DBI;
 use POSIX qw(strftime mktime);
+use Apache::lonnet;
 
 my $mysqluser;
 my $mysqlpassword;
+my $mysqldatabase;
+my %db_config;
 
 sub set_mysql_user_and_password {
     # If we are running under Apache and LONCAPA, use the LON-CAPA 
     # user and password.  Otherwise...? ? ? ?
-    ($mysqluser,$mysqlpassword) = @_;
+    my ($input_mysqluser,$input_mysqlpassword,$input_mysqldatabase) = @_;
+    if (! defined($mysqldatabase)) {
+        $mysqldatabase = 'loncapa';
+    }
+    if (defined($input_mysqldatabase)) {
+        $mysqldatabase = $input_mysqldatabase;
+    }
     if (! defined($mysqluser) || ! defined($mysqlpassword)) {
         if (! eval 'require Apache::lonnet();') {
             $mysqluser = 'www';
@@ -49,6 +58,12 @@ sub set_mysql_user_and_password {
             $mysqlpassword = '';
         }
     }
+    if (defined($input_mysqluser)) {
+        $mysqluser = $input_mysqluser;
+    } 
+    if (defined($input_mysqlpassword)) {
+        $mysqlpassword = $input_mysqlpassword;
+    }
 }
 
 ######################################################################
@@ -72,14 +87,15 @@ and provide a common interface.  The goa
 a complete reimplementation of the DBI interface.  Instead we try to 
 make using mysql as painless as possible.
 
-Each table has a numeric ID that is a parameter to most lonmysql functions.
-The table id is returned by &create_table.  
-If you lose the table id, it is lost forever.
-The table names in MySQL correspond to 
-$ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$table_id.  If the table id 
-is non-numeric, it is assumed to be the full name of a table.  If you pass
-the table id in a form, you MUST ensure that what you send to lonmysql is
-numeric, otherwise you are opening up all the tables in the MySQL database.
+Each table has a numeric ID that is a parameter to most lonmysql
+functions.  The table id is returned by &create_table.  If you lose
+the table id, it is lost forever.  The table names in MySQL correspond
+to $env{'user.name'}.'_'.$env{'user.domain'}.'_'.$table_id. (With all
+non-word characters removed form user.name and user.domain) If the
+table id is non-numeric, it is assumed to be the full name of a table.
+If you pass the table id in a form, you MUST ensure that what you send
+to lonmysql is numeric, otherwise you are opening up all the tables in
+the MySQL database.
 
 =over 4
 
@@ -349,7 +365,7 @@ sub connect_to_db {
     if (! defined($mysqluser) || ! defined($mysqlpassword)) {
         &set_mysql_user_and_password();
     }
-    if (! ($dbh = DBI->connect("DBI:mysql:loncapa",$mysqluser,$mysqlpassword,
+    if (! ($dbh = DBI->connect("DBI:mysql:$mysqldatabase",$mysqluser,$mysqlpassword,
                                { RaiseError=>0,PrintError=>0}))) {
         $debugstring = "Unable to connect to loncapa database.";    
         if (! defined($dbh)) {
@@ -361,6 +377,22 @@ sub connect_to_db {
         return undef;
     }
     $debugstring = "Successfully connected to loncapa database.";    
+    # Determine DB configuration
+    undef(%db_config);
+    my $sth = $dbh->prepare("SHOW VARIABLES");
+    $sth->execute();
+    if ($sth->err()) {
+        $debugstring = "Unable to retrieve db config variables";
+        return undef;
+    }
+    foreach my $row (@{$sth->fetchall_arrayref}) {
+        $db_config{$row->[0]} = $row->[1];
+    }
+    #&Apache::lonnet::logthis("MySQL configuration variables");
+    #while (my ($k,$v) = each(%db_config)) {
+    #    &Apache::lonnet::logthis("    '$k' => '$v'");
+    #}
+    #
     return 1;
 }
 
@@ -540,10 +572,6 @@ sub update_table_info {
     #
     # Get MySQLs table status information.
     #
-    my @tabledesc = qw/
-        Name Type Row_format Rows Avg_row_length Data_length
-            Max_data_length Index_length Data_free Auto_increment 
-                Create_time Update_time Check_time Create_options Comment /;
     my $db_command = "SHOW TABLE STATUS FROM loncapa LIKE '$tablename'";
     my $sth = $dbh->prepare($db_command);
     $sth->execute();
@@ -553,14 +581,15 @@ sub update_table_info {
         &disconnect_from_db();
         return undef;
     }
+    my @column_name = @{$sth->{NAME}};
     #
     my @info=$sth->fetchrow_array;
     for (my $i=0;$i<= $#info ; $i++) {
-        if ($tabledesc[$i] !~ /^(Create_|Update_|Check_)time$/) {
-            $Tables{$tablename}->{$tabledesc[$i]}= 
+        if ($column_name[$i] =~ /^(Create_|Update_|Check_)time$/) {
+            $Tables{$tablename}->{$column_name[$i]}= 
                 &unsqltime($info[$i]);
         } else {
-            $Tables{$tablename}->{$tabledesc[$i]}= $info[$i];
+            $Tables{$tablename}->{$column_name[$i]}= $info[$i];
         }
     }
     #
@@ -796,6 +825,25 @@ sub build_table_creation_request {
 
 =pod
 
+=item &get_table_prefix()
+
+returns the cleaned version of user.name and user.domain for us in table names
+
+=cut
+
+###############################
+sub get_table_prefix {
+    my $clean_name   = $env{'user.name'};
+    my $clean_domain = $env{'user.domain'};
+    $clean_name =~ s/\W//g;
+    $clean_domain =~ s/\W//g;
+    return $clean_name.'_'.$clean_domain.'_';
+}
+
+###############################
+
+=pod
+
 =item &get_new_table_id()
 
 Used internally to prevent table name collisions.
@@ -806,8 +854,9 @@ Used internally to prevent table name co
 sub get_new_table_id {
     my $newid = 0;
     my @tables = &tables_in_db();
+    my $prefix = &get_table_prefix();
     foreach (@tables) {
-        if (/^$ENV{'user.name'}_$ENV{'user.domain'}_(\d+)$/) {
+        if (/^\Q$prefix\E(\d+)$/) {
             $newid = $1 if ($1 > $newid);
         }
     }
@@ -963,6 +1012,7 @@ sub bulk_store_rows {
         $request .= '('.join(',',@$row).'),';
     }
     $request =~ s/,$//;
+    # $debugstring = "Executed ".$/.$request; # commented out - this is big
     $dbh->do($request);
     if ($dbh->err) {
         $errorstring = 'Attempted '.$/.$request.$/.'Got error '.$dbh->errstr();
@@ -1045,16 +1095,29 @@ Returns undef on error.
 =cut
 
 ###########################################
+
+########## Show-Tables Cache
+my $have_read_tables = 0;
+my $dbh_sth;
+##########
+
 sub tables_in_db {
     return undef if (!defined(&connect_to_db()));
-    my $sth=$dbh->prepare('SHOW TABLES');
-    $sth->execute();
-    $sth->execute();
-    my $aref = $sth->fetchall_arrayref;
-    if ($sth->err()) {
+    
+    ########## Show-Tables Cache
+    if(!$have_read_tables) { 
+     $dbh_sth=$dbh->prepare('SHOW TABLES');
+     $have_read_tables = 1;
+    }   
+    $dbh_sth->execute();
+    #$dbh_sth->execute(); # Removed strange execute - from release 119
+    ##########    
+    
+    my $aref = $dbh_sth->fetchall_arrayref;
+    if ($dbh_sth->err()) {
         $errorstring = 
             "$dbh ATTEMPTED:\n".'fetchall_arrayref after SHOW TABLES'.
-            "\nRESULTING ERROR:\n".$sth->errstr;
+            "\nRESULTING ERROR:\n".$dbh_sth->errstr;
         return undef;
     }
     my @table_list;
@@ -1085,7 +1148,7 @@ sub translate_id {
     # id should be a digit.  If it is not a digit we assume the given id
     # is complete and does not need to be translated.
     return $id if ($id =~ /\D/);  
-    return $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.$id;
+    return &get_table_prefix().$id;
 }
 
 ###########################################
@@ -1195,7 +1258,7 @@ Fixes a table name so that it will work
 ##########################################
 sub fix_table_name {
     my ($name) = @_;
-    $name =~ s/^(\d+e\d+)/_$1/;
+    $name =~ s/^(\d+[eE]\d+)/_$1/;
     return $name;
 }