[LON-CAPA-cvs] cvs: loncom /interface loncoursedata.pm

matthew lon-capa-cvs@mail.lon-capa.org
Tue, 25 Mar 2003 22:29:31 -0000


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--matthew1048631371
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matthew		Tue Mar 25 17:29:31 2003 EDT

  Modified files:              
    /loncom/interface	loncoursedata.pm 
  Log:
  Removed &DownloadClasslist, &DownloadCourseInformation, &ProcessTopResourceMap,
  &ProcessClasslist, &ProcessStudentData, &ExtractStudentData,
  &CheckDateStampError, &TestCacheData, &DownloadStudentCourseData, 
  &DownloadStudentCourseDataSeparate, and &CheckForResidualDownload
  
  Local Caching:
  Added flags to &get_part_id, &get_symb_id, and &get_student_id to fix a bug
  where they automatically added the part/symb/student to the table the first
  time they were called instead of reading the table to get the value.
  &get_current_state was reduced in size by moving its initialization code
  to &setup_table_names.  &setup_table_names was relocated to the tail of the
  local caching code.
  
  Statistics:
  Added &get_problem_statistics.  It does not currently limit the statistics
  to a set of students, but will soon.  Classification of students is also
  unimplemented.  
  
  Added SQL helper function &execute_SQL_request to encapsulate the
  'prepare request, execute request, get returned row' sequence and make 
  debugging easier.
  
  
--matthew1048631371
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Content-Disposition: attachment; filename="matthew-20030325172931.txt"

Index: loncom/interface/loncoursedata.pm
diff -u loncom/interface/loncoursedata.pm:1.60 loncom/interface/loncoursedata.pm:1.61
--- loncom/interface/loncoursedata.pm:1.60	Fri Mar 21 11:04:10 2003
+++ loncom/interface/loncoursedata.pm	Tue Mar 25 17:29:31 2003
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: loncoursedata.pm,v 1.60 2003/03/21 16:04:10 matthew Exp $
+# $Id: loncoursedata.pm,v 1.61 2003/03/25 22:29:31 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -66,203 +66,6 @@
 
 =cut
 
-# ----- DOWNLOAD INFORMATION -------------------------------------------
-
-=pod
-
-=item &DownloadClasslist()
-
-Collects lastname, generation, middlename, firstname, PID, and section for each
-student from their environment database.  The section data is also download, though
-it is in a rough format, and is processed later.  The list of students is built from
-collecting a classlist for the course that is to be displayed.  Once the classlist
-has been downloaded, its date stamp is recorded.  Unless the datestamp for the
-class database is reset or is modified, this data will not be downloaded again.  
-Also, there was talk about putting the fullname and section
-and perhaps other pieces of data into the classlist file.  This would
-reduce the number of different file accesses and reduce the amount of 
-processing on this side.
-
-=over 4
-
-Input: $courseID, $lastDownloadTime, $c
-
-$courseID:  The id of the course
-
-$lastDownloadTime:  This is the date stamp for when this information was
-last gathered.  If it is set to Not downloaded, it will gather the data
-again, though it currently does not remove the old data.
-
-$c: The connection class that can determine if the browser has aborted.  It
-is used to short circuit this function so that it does not continue to 
-get information when there is no need.
-
-Output: \%classlist
-
-\%classlist: A pointer to a hash containing the following data:
-
--A list of student name:domain (as keys) (known below as $name)
-
--A hash pointer for each student containing lastname, generation, firstname,
-middlename, and PID : Key is $name.studentInformation
-
--A hash pointer to each students section data : Key is $name.section
-
--If there was an error in dump, it will be returned in the hash.  See
-the error codes for dump in lonnet.  Also, an error key will be 
-generated if an abort occurs.
-
-=back
-
-=cut
-
-sub DownloadClasslist {
-    my ($courseID, $lastDownloadTime, $c)=@_;
-    my ($courseDomain,$courseNumber)=split(/\_/,$courseID);
-    my %classlist;
-
-    my $modifiedTime = &Apache::lonnet::GetFileTimestamp($courseDomain, 
-                                                         $courseNumber,
-                                                         'classlist.db', 
-                                 $Apache::lonnet::perlvar{'lonUsersDir'});
-
-    # Always download the information if lastDownloadTime is set to
-    # Not downloaded, otherwise it is only downloaded if the file
-    # has been updated and has a more recent date stamp
-    if($lastDownloadTime ne 'Not downloaded' &&
-       $lastDownloadTime >= $modifiedTime && $modifiedTime >= 0) {
-        # Data is not gathered so return UpToDate as true.  This
-        # will be interpreted in ProcessClasslist
-        $classlist{'lastDownloadTime'}=time;
-        $classlist{'UpToDate'} = 'true';
-        return \%classlist;
-    }
-
-    %classlist=&Apache::lonnet::dump('classlist',$courseDomain, $courseNumber);
-    foreach(keys (%classlist)) {
-        if(/^(con_lost|error|no_such_host)/i) {
-	    return;
-        }
-    }
-
-    foreach my $name (keys(%classlist)) {
-        if(defined($c) && ($c->aborted())) {
-            $classlist{'error'}='aborted';
-            return \%classlist;
-        }
-
-        my ($studentName,$studentDomain) = split(/\:/,$name);
-        # Download student environment data, specifically the full name and id.
-        my %studentInformation=&Apache::lonnet::get('environment',
-                                                    ['lastname','generation',
-                                                     'firstname','middlename',
-                                                     'id'],
-                                                    $studentDomain,
-                                                    $studentName);
-        $classlist{$name.':studentInformation'}=\%studentInformation;
-
-        if($c->aborted()) {
-            $classlist{'error'}='aborted';
-            return \%classlist;
-        }
-
-        #Section
-        my %section=&Apache::lonnet::dump('roles',$studentDomain,$studentName);
-        $classlist{$name.':sections'}=\%section;
-    }
-
-    $classlist{'UpToDate'} = 'false';
-    $classlist{'lastDownloadTime'}=time;
-
-    return \%classlist;
-}
-
-=pod
-
-=item &DownloadCourseInformation()
-
-Dump of all the course information for a single student.  The data can be
-pruned by making use of dumps regular expression arguement.  This function
-also takes a regular expression which it passes straight through to dump.  
-The data is no escaped, because it is done elsewhere.  It also
-checks the timestamp of the students course database file and only downloads
-if it has been modified since the last download.
-
-=over 4
-
-Input: $namedata, $courseID, $lastDownloadTime, $WhatIWant
-
-$namedata: student name:domain
-
-$courseID:  The id of the course
-
-$lastDownloadTime:  This is the date stamp for when this information was
-last gathered.  If it is set to Not downloaded, it will gather the data
-again, though it currently does not remove the old data.
-
-$WhatIWant:  Regular expression used to get selected data with dump
-
-Output: \%courseData
-
-\%courseData:  A hash pointer to the raw data from the students course
-database.
-
-=back
-
-=cut
-
-sub DownloadCourseInformation {
-    my ($namedata,$courseID,$lastDownloadTime,$WhatIWant)=@_;
-    my %courseData;
-    my ($name,$domain) = split(/\:/,$namedata);
-
-    my $modifiedTime = &Apache::lonnet::GetFileTimestamp($domain, $name,
-                                      $courseID.'.db', 
-                                      $Apache::lonnet::perlvar{'lonUsersDir'});
-
-    if($lastDownloadTime ne 'Not downloaded' && 
-       $lastDownloadTime >= $modifiedTime && $modifiedTime >= 0) {
-        # Data is not gathered so return UpToDate as true.  This
-        # will be interpreted in ProcessClasslist
-        $courseData{$namedata.':lastDownloadTime'}=time;
-        $courseData{$namedata.':UpToDate'} = 'true';
-        return \%courseData;
-    }
-
-    # Download course data
-    if(!defined($WhatIWant)) {
-        # set the regular expression to everything by setting it to period
-        $WhatIWant = '.';
-    }
-    %courseData=&Apache::lonnet::dump($courseID, $domain, $name, $WhatIWant);
-    $courseData{'UpToDate'} = 'false';
-    $courseData{'lastDownloadTime'}=time;
-
-    my %newData;
-    foreach (keys(%courseData)) {
-        # need to have the keys to be prepended with the name:domain of the
-        # student to reduce data collision later.
-        $newData{$namedata.':'.$_} = $courseData{$_};
-    }
-
-    return \%newData;
-}
-
-# ----- END DOWNLOAD INFORMATION ---------------------------------------
-
-=pod
-
-=head1 PROCESSING FUNCTIONS
-
-These functions process all the data for all the students.  Also, they
-are the functions that access the cache database for writing the majority of
-the time.  The downloading and caching were separated to reduce problems 
-with stopping downloading then can not tie hash to database later.
-
-=cut
-
-# ----- PROCESSING FUNCTIONS ---------------------------------------
-
 ####################################################
 ####################################################
 
@@ -277,9 +80,9 @@
 
 The returned structure is a hash reference. 
 
-{ title  => 'title',
-  symb   => 'symb',
-  source => '/s/o/u/r/c/e',
+{ title => 'title',
+  symb  => 'symb',
+  src   => '/s/o/u/r/c/e',
   type  => (container|assessment),
   num_assess   => 2,               # only for container
   parts        => [11,13,15],      # only for assessment
@@ -301,12 +104,13 @@
     my $fn=$ENV{'request.course.fn'};
     ##
     ## use navmaps
-    my $navmap = Apache::lonnavmaps::navmap->new($fn.".db",$fn."_parms.db",
-                                                 1,0);
+    my $navmap = Apache::lonnavmaps::navmap->new(Apache->request,$fn.".db",
+                                                 $fn."_parms.db",1,0);
     if (!defined($navmap)) {
         return 'Can not open Coursemap';
     }
     my $iterator = $navmap->getIterator(undef, undef, undef, 1);
+    my $curRes = $iterator->next(); # Top level sequence
     ##
     ## Prime the pump 
     ## 
@@ -333,7 +137,7 @@
     # We need to keep track of which sequences contain homework problems
     # 
     my $previous;
-    my $curRes = $iterator->next(); # BEGIN_MAP
+    $curRes = $iterator->next(); # BEGIN_MAP
     $curRes = $iterator->next(); # The first item in the top level map.
     while (scalar(@Nested_Sequences)) {
         $previous = $curRes;
@@ -383,748 +187,6 @@
     return ($top,\@Sequences,\@Assessments);
 }
 
-#################################################
-#################################################
-
-=pod
-
-=item &ProcessTopResourceMap()
-
-Trace through the "big hash" created in rat/lonuserstate.pm::loadmap.  
-Basically, this function organizes a subset of the data and stores it in
-cached data.  The data stored is the problems, sequences, sequence titles,
-parts of problems, and their ordering.  Column width information is also 
-partially handled here on a per sequence basis.
-
-=over 4
-
-Input: $cache, $c
-
-$cache:  A pointer to a hash to store the information
-
-$c:  The connection class used to determine if an abort has been sent to the 
-browser
-
-Output: A string that contains an error message or "OK" if everything went 
-smoothly.
-
-=back
-
-=cut
-
-sub ProcessTopResourceMap {
-    my ($cache,$c)=@_;
-    my %hash;
-    my $fn=$ENV{'request.course.fn'};
-    if(-e "$fn.db") {
-	my $tieTries=0;
-	while($tieTries < 3) {
-            if($c->aborted()) {
-                return;
-            }
-	    if(tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640)) {
-		last;
-	    }
-	    $tieTries++;
-	    sleep 1;
-	}
-	if($tieTries >= 3) {
-            return 'Coursemap undefined.';
-        }
-    } else {
-        return 'Can not open Coursemap.';
-    }
-
-    my $oldkeys;
-    delete $cache->{'OptionResponses'};
-    if(defined($cache->{'ResourceKeys'})) {
-        $oldkeys = $cache->{'ResourceKeys'};
-        foreach (split(':::', $cache->{'ResourceKeys'})) {
-            delete $cache->{$_};
-        }
-        delete $cache->{'ResourceKeys'};
-    }
-
-    # Initialize state machine.  Set information pointing to top level map.
-    my (@sequences, @currentResource, @finishResource);
-    my ($currentSequence, $currentResourceID, $lastResourceID);
-
-    $currentResourceID=$hash{'ids_'.
-      &Apache::lonnet::clutter($ENV{'request.course.uri'})};
-    push(@currentResource, $currentResourceID);
-    $lastResourceID=-1;
-    $currentSequence=-1;
-    my $topLevelSequenceNumber = $currentSequence;
-
-    my %sequenceRecord;
-    my %allkeys;
-    while(1) {
-        if($c->aborted()) {
-            last;
-        }
-	# HANDLE NEW SEQUENCE!
-	#if page || sequence
-	if(defined($hash{'map_pc_'.$hash{'src_'.$currentResourceID}}) &&
-           !defined($sequenceRecord{$currentResourceID})) {
-            $sequenceRecord{$currentResourceID}++;
-	    push(@sequences, $currentSequence);
-	    push(@currentResource, $currentResourceID);
-	    push(@finishResource, $lastResourceID);
-
-	    $currentSequence=$hash{'map_pc_'.$hash{'src_'.$currentResourceID}};
-
-            # Mark sequence as containing problems.  If it doesn't, then
-            # it will be removed when processing for this sequence is
-            # complete.  This allows the problems in a sequence
-            # to be outputed before problems in the subsequences
-            if(!defined($cache->{'orderedSequences'})) {
-                $cache->{'orderedSequences'}=$currentSequence;
-            } else {
-                $cache->{'orderedSequences'}.=':'.$currentSequence;
-            }
-            $allkeys{'orderedSequences'}++;
-
-	    $lastResourceID=$hash{'map_finish_'.
-				  $hash{'src_'.$currentResourceID}};
-	    $currentResourceID=$hash{'map_start_'.
-				     $hash{'src_'.$currentResourceID}};
-
-	    if(!($currentResourceID) || !($lastResourceID)) {
-		$currentSequence=pop(@sequences);
-		$currentResourceID=pop(@currentResource);
-		$lastResourceID=pop(@finishResource);
-		if($currentSequence eq $topLevelSequenceNumber) {
-		    last;
-		}
-	    }
-            next;
-	}
-
-	# Handle gradable resources: exams, problems, etc
-	$currentResourceID=~/(\d+)\.(\d+)/;
-        my $partA=$1;
-        my $partB=$2;
-	if($hash{'src_'.$currentResourceID}=~
-	   /\.(problem|exam|quiz|assess|survey|form)$/ &&
-	   $partA eq $currentSequence && 
-           !defined($sequenceRecord{$currentSequence.':'.
-                                    $currentResourceID})) {
-            $sequenceRecord{$currentSequence.':'.$currentResourceID}++;
-	    my $Problem = &Apache::lonnet::symbclean(
-			  &Apache::lonnet::declutter($hash{'map_id_'.$partA}).
-			  '___'.$partB.'___'.
-			  &Apache::lonnet::declutter($hash{'src_'.
-							 $currentResourceID}));
-
-	    $cache->{$currentResourceID.':problem'}=$Problem;
-            $allkeys{$currentResourceID.':problem'}++;
-	    if(!defined($cache->{$currentSequence.':problems'})) {
-		$cache->{$currentSequence.':problems'}=$currentResourceID;
-	    } else {
-		$cache->{$currentSequence.':problems'}.=
-		    ':'.$currentResourceID;
-	    }
-            $allkeys{$currentSequence.':problems'}++;
-
-	    my $meta=$hash{'src_'.$currentResourceID};
-#            $cache->{$currentResourceID.':title'}=
-#                &Apache::lonnet::metdata($meta,'title');
-            $cache->{$currentResourceID.':title'}=
-                $hash{'title_'.$currentResourceID};
-            $allkeys{$currentResourceID.':title'}++;
-            $cache->{$currentResourceID.':source'}=
-                $hash{'src_'.$currentResourceID};
-            $allkeys{$currentResourceID.':source'}++;
-
-            # Get Parts for problem
-            my %beenHere;
-            foreach (split(/\,/,&Apache::lonnet::metadata($meta,'packages'))) {
-                if(/^\w+response_\d+.*/) {
-                    my (undef, $partId, $responseId) = split(/_/,$_);
-                    if($beenHere{'p:'.$partId} ==  0) {
-                        $beenHere{'p:'.$partId}++;
-                        if(!defined($cache->{$currentSequence.':'.
-                                            $currentResourceID.':parts'})) {
-                            $cache->{$currentSequence.':'.$currentResourceID.
-                                     ':parts'}=$partId;
-                        } else {
-                            $cache->{$currentSequence.':'.$currentResourceID.
-                                     ':parts'}.=':'.$partId;
-                        }
-                        $allkeys{$currentSequence.':'.$currentResourceID.
-                                  ':parts'}++;
-                    }
-                    if($beenHere{'r:'.$partId.':'.$responseId} == 0) {
-                        $beenHere{'r:'.$partId.':'.$responseId}++;
-                        if(!defined($cache->{$currentSequence.':'.
-                                             $currentResourceID.':'.$partId.
-                                             ':responseIDs'})) {
-                            $cache->{$currentSequence.':'.$currentResourceID.
-                                     ':'.$partId.':responseIDs'}=$responseId;
-                        } else {
-                            $cache->{$currentSequence.':'.$currentResourceID.
-                                     ':'.$partId.':responseIDs'}.=':'.
-                                                                  $responseId;
-                        }
-                        $allkeys{$currentSequence.':'.$currentResourceID.':'.
-                                     $partId.':responseIDs'}++;
-                    }
-                    if(/^optionresponse/ && 
-                       $beenHere{'o:'.$partId.':'.$currentResourceID} == 0) {
-                        $beenHere{'o:'.$partId.$currentResourceID}++;
-                        if(defined($cache->{'OptionResponses'})) {
-                            $cache->{'OptionResponses'}.= ':::'.
-                                $currentSequence.':'.$currentResourceID.':'.
-                                $partId.':'.$responseId;
-                        } else {
-                            $cache->{'OptionResponses'}= $currentSequence.':'.
-                                $currentResourceID.':'.
-                                $partId.':'.$responseId;
-                        }
-                        $allkeys{'OptionResponses'}++;
-                    }
-                }
-            }
-        }
-
-	# if resource == finish resource, then it is the end of a sequence/page
-	if($currentResourceID eq $lastResourceID) {
-	    # pop off last resource of sequence
-	    $currentResourceID=pop(@currentResource);
-	    $lastResourceID=pop(@finishResource);
-
-	    if(defined($cache->{$currentSequence.':problems'})) {
-		# Capture sequence information here
-		$cache->{$currentSequence.':title'}=
-		    $hash{'title_'.$currentResourceID};
-                $allkeys{$currentSequence.':title'}++;
-                $cache->{$currentSequence.':source'}=
-                    $hash{'src_'.$currentResourceID};
-                $allkeys{$currentSequence.':source'}++;
-
-                my $totalProblems=0;
-                foreach my $currentProblem (split(/\:/,
-                                               $cache->{$currentSequence.
-                                               ':problems'})) {
-                    foreach (split(/\:/,$cache->{$currentSequence.':'.
-                                                   $currentProblem.
-                                                   ':parts'})) {
-                        $totalProblems++;
-                    }
-                }
-		my @titleLength=split(//,$cache->{$currentSequence.
-                                                    ':title'});
-                # $extra is 5 for problems correct and 3 for space
-                # between problems correct and problem output
-                my $extra = 8;
-		if(($totalProblems + $extra) > (scalar @titleLength)) {
-		    $cache->{$currentSequence.':columnWidth'}=
-                        $totalProblems + $extra;
-		} else {
-		    $cache->{$currentSequence.':columnWidth'}=
-                        (scalar @titleLength);
-		}
-                $allkeys{$currentSequence.':columnWidth'}++;
-	    } else {
-                # Remove sequence from list, if it contains no problems to
-                # display.
-                $cache->{'orderedSequences'}=~s/$currentSequence//;
-                $cache->{'orderedSequences'}=~s/::/:/g;
-                $cache->{'orderedSequences'}=~s/^:|:$//g;
-            }
-
-	    $currentSequence=pop(@sequences);
-	    if($currentSequence eq $topLevelSequenceNumber) {
-		last;
-	    }
-        }
-
-	# MOVE!!!
-	# move to next resource
-	unless(defined($hash{'to_'.$currentResourceID})) {
-	    # big problem, need to handle.  Next is probably wrong
-            my $errorMessage = 'Big problem in ';
-            $errorMessage .= 'loncoursedata::ProcessTopLevelMap.';
-            $errorMessage .= "  bighash to_$currentResourceID not defined!";
-            &Apache::lonnet::logthis($errorMessage);
-	    if (!defined($currentResourceID)) {last;}
-	}
-	my @nextResources=();
-	foreach (split(/\,/,$hash{'to_'.$currentResourceID})) {
-            if(!defined($sequenceRecord{$currentSequence.':'.
-                                        $hash{'goesto_'.$_}})) {
-                push(@nextResources, $hash{'goesto_'.$_});
-            }
-	}
-	push(@currentResource, @nextResources);
-	# Set the next resource to be processed
-	$currentResourceID=pop(@currentResource);
-    }
-
-    my @theKeys = keys(%allkeys);
-    my $newkeys = join(':::', @theKeys);
-    $cache->{'ResourceKeys'} = join(':::', $newkeys);
-    if($newkeys ne $oldkeys) {
-        $cache->{'ResourceUpdated'} = 'true';
-    } else {
-        $cache->{'ResourceUpdated'} = 'false';
-    }
-
-    unless (untie(%hash)) {
-        &Apache::lonnet::logthis("<font color=blue>WARNING: ".
-                                 "Could not untie coursemap $fn (browse)".
-                                 ".</font>"); 
-    }
-
-    return 'OK';
-}
-
-=pod
-
-=item &ProcessClasslist()
-
-Taking the class list dumped from &DownloadClasslist(), all the 
-students and their non-class information is processed using the 
-&ProcessStudentInformation() function.  A date stamp is also recorded for
-when the data was processed.
-
-Takes data downloaded for a student and breaks it up into managable pieces and 
-stored in cache data.  The username, domain, class related date, PID, 
-full name, and section are all processed here.
-
-=over 4
-
-Input: $cache, $classlist, $courseID, $ChartDB, $c
-
-$cache: A hash pointer to store the data
-
-$classlist:  The hash of data collected about a student from 
-&DownloadClasslist().  The hash contains a list of students, a pointer 
-to a hash of student information for each student, and each students section 
-number.
-
-$courseID:  The course ID
-
-$ChartDB:  The name of the cache database file.
-
-$c:  The connection class used to determine if an abort has been sent to the 
-browser
-
-Output: @names
-
-@names:  An array of students whose information has been processed, and are to 
-be considered in an arbitrary order.  The entries in @names are of the form
-username:domain.
-
-The values in $cache are as follows:
-
- *NOTE: for the following $name implies username:domain
- $name.':error'                  only defined if an error occured.  Value
-                                 contains the error message
- $name.':lastDownloadTime'       unconverted time of the last update of a
-                                 student\'s course data
- $name.'updateTime'              coverted time of the last update of a 
-                                 student\'s course data
- $name.':username'               username of a student
- $name.':domain'                 domain of a student
- $name.':fullname'               full name of a student
- $name.':id'                     PID of a student
- $name.':Status'                 active/expired status of a student
- $name.':section'                section of a student
-
-=back
-
-=cut
-
-sub ProcessClasslist {
-    my ($cache,$classlist,$courseID,$c)=@_;
-    my @names=();
-
-    $cache->{'ClasslistTimeStamp'}=$classlist->{'lastDownloadTime'};
-    if($classlist->{'UpToDate'} eq 'true') {
-        return split(/:::/,$cache->{'NamesOfStudents'});;
-    }
-
-    foreach my $name (keys(%$classlist)) {
-        if($name =~ /\:section/ || $name =~ /\:studentInformation/ ||
-           $name eq '' || $name eq 'UpToDate' || $name eq 'lastDownloadTime') {
-            next;
-        }
-        if($c->aborted()) {
-            return ();
-        }
-        my $studentInformation = $classlist->{$name.':studentInformation'};
-        my $date = $classlist->{$name};
-        my ($studentName,$studentDomain) = split(/\:/,$name);
-
-        $cache->{$name.':username'}=$studentName;
-        $cache->{$name.':domain'}=$studentDomain;
-        # Initialize timestamp for student
-        if(!defined($cache->{$name.':lastDownloadTime'})) {
-            $cache->{$name.':lastDownloadTime'}='Not downloaded';
-            $cache->{$name.':updateTime'}=' Not updated';
-        }
-
-        my $error = 0;
-        foreach(keys(%$studentInformation)) {
-            if(/^(con_lost|error|no_such_host)/i) {
-                $cache->{$name.':error'}=
-                    'Could not download student environment data.';
-                $cache->{$name.':fullname'}='';
-                $cache->{$name.':id'}='';
-                $error = 1;
-            }
-        }
-        next if($error);
-        push(@names,$name);
-        $cache->{$name.':fullname'}=&ProcessFullName(
-                                          $studentInformation->{'lastname'},
-                                          $studentInformation->{'generation'},
-                                          $studentInformation->{'firstname'},
-                                          $studentInformation->{'middlename'});
-        $cache->{$name.':id'}=$studentInformation->{'id'};
-
-        my ($end, $start)=split(':',$date);
-        $courseID=~s/\_/\//g;
-        $courseID=~s/^(\w)/\/$1/;
-
-        my $sec='';
-        my $sectionData = $classlist->{$name.':sections'};
-        foreach my $key (keys (%$sectionData)) {
-            my $value = $sectionData->{$key};
-            if ($key=~/^$courseID(?:\/)*(\w+)*\_st$/) {
-                my $tempsection=$1;
-                if($key eq $courseID.'_st') {
-                    $tempsection='';
-                }
-                my (undef,$roleend,$rolestart)=split(/\_/,$value);
-                if($roleend eq $end && $rolestart eq $start) {
-                    $sec = $tempsection;
-                    last;
-                }
-            }
-        }
-
-        my $status='Expired';
-        if(((!$end) || time < $end) && ((!$start) || (time > $start))) {
-            $status='Active';
-        }
-        $cache->{$name.':Status'}=$status;
-        $cache->{$name.':section'}=$sec;
-
-        if($sec eq '' || !defined($sec) || $sec eq ' ') {
-            $sec = 'none';
-        }
-        if(defined($cache->{'sectionList'})) {
-            if($cache->{'sectionList'} !~ /(^$sec:|^$sec$|:$sec$|:$sec:)/) {
-                $cache->{'sectionList'} .= ':'.$sec;
-            }
-        } else {
-            $cache->{'sectionList'} = $sec;
-        }
-    }
-
-    $cache->{'ClasslistTimestamp'}=time;
-    $cache->{'NamesOfStudents'}=join(':::',@names);
-
-    return @names;
-}
-
-=pod
-
-=item &ProcessStudentData()
-
-Takes the course data downloaded for a student in 
-&DownloadCourseInformation() and breaks it up into key value pairs
-to be stored in the cached data.  The keys are comprised of the 
-$username:$domain:$keyFromCourseDatabase.  The student username:domain is
-stored away signifying that the students information has been downloaded and 
-can be reused from cached data.
-
-=over 4
-
-Input: $cache, $courseData, $name
-
-$cache: A hash pointer to store data
-
-$courseData:  A hash pointer that points to the course data downloaded for a 
-student.
-
-$name:  username:domain
-
-Output: None
-
-*NOTE:  There is no output, but an error message is stored away in the cache 
-data.  This is checked in &FormatStudentData().  The key username:domain:error 
-will only exist if an error occured.  The error is an error from 
-&DownloadCourseInformation().
-
-=back
-
-=cut
-
-sub ProcessStudentData {
-    my ($cache,$courseData,$name)=@_;
-
-    if(!&CheckDateStampError($courseData, $cache, $name)) {
-        return;
-    }
-
-    # This little delete thing, should not be here.  Move some other
-    # time though.
-    if(defined($cache->{$name.':keys'})) {
-	foreach (split(':::', $cache->{$name.':keys'})) {
-	    delete $cache->{$name.':'.$_};
-	}
-        delete $cache->{$name.':keys'};
-    }
-
-    my %courseKeys;
-    # user name:domain was prepended earlier in DownloadCourseInformation
-    foreach (keys %$courseData) {
-	my $currentKey = $_;
-	$currentKey =~ s/^$name//;
-	$courseKeys{$currentKey}++;
-        $cache->{$_}=$courseData->{$_};
-    }
-
-    $cache->{$name.':keys'} = join(':::', keys(%courseKeys));
-
-    return;
-}
-
-=pod
-
-=item &ExtractStudentData()
-
-HISTORY: This function originally existed in every statistics module,
-and performed different tasks, the had some overlap.  Due to the need
-for the data from the different modules, they were combined into
-a single function.
-
-This function now extracts all the necessary course data for a student
-from what was downloaded from their homeserver.  There is some extra
-time overhead compared to the ProcessStudentInformation function, but
-it would have had to occurred at some point anyways.  This is now
-typically called while downloading the data it will process.  It is
-the brother function to ProcessStudentInformation.
-
-=over 4
-
-Input: $input, $output, $data, $name
-
-$input: A hash that contains the input data to be processed
-
-$output: A hash to contain the processed data
-
-$data: A hash containing the information on what is to be
-processed and how (basically).
-
-$name:  username:domain
-
-The input is slightly different here, but is quite simple.
-It is currently used where the $input, $output, and $data
-can and are often the same hashes, but they do not need
-to be.
-
-Output: None
-
-*NOTE:  There is no output, but an error message is stored away in the cache 
-data.  This is checked in &FormatStudentData().  The key username:domain:error 
-will only exist if an error occured.  The error is an error from 
-&DownloadCourseInformation().
-
-=back
-
-=cut
-
-sub ExtractStudentData {
-    my ($input, $output, $data, $name)=@_;
-
-    if(!&CheckDateStampError($input, $data, $name)) {
-        return;
-    }
-
-    # This little delete thing, should not be here.  Move some other
-    # time though.
-    my %allkeys;
-    if(defined($output->{$name.':keys'})) {
-	foreach (split(':::', $output->{$name.':keys'})) {
-	    delete $output->{$name.':'.$_};
-	}
-        delete $output->{$name.':keys'};
-    }
-
-    my ($username,$domain)=split(':',$name);
-
-    my $Version;
-    my $problemsCorrect = 0;
-    my $totalProblems   = 0;
-    my $problemsSolved  = 0;
-    my $numberOfParts   = 0;
-    my $totalAwarded    = 0;
-    foreach my $sequence (split(':', $data->{'orderedSequences'})) {
-        foreach my $problemID (split(':', $data->{$sequence.':problems'})) {
-            my $problem = $data->{$problemID.':problem'};
-            my $LatestVersion = $input->{$name.':version:'.$problem};
-
-            # Output dashes for all the parts of this problem if there
-            # is no version information about the current problem.
-            $output->{$name.':'.$problemID.':NoVersion'} = 'false';
-            $allkeys{$name.':'.$problemID.':NoVersion'}++;
-            if(!$LatestVersion) {
-                foreach my $part (split(/\:/,$data->{$sequence.':'.
-                                                      $problemID.
-                                                      ':parts'})) {
-                    $output->{$name.':'.$problemID.':'.$part.':tries'} = 0;
-                    $output->{$name.':'.$problemID.':'.$part.':awarded'} = 0;
-                    $output->{$name.':'.$problemID.':'.$part.':code'} = ' ';
-		    $allkeys{$name.':'.$problemID.':'.$part.':tries'}++;
-		    $allkeys{$name.':'.$problemID.':'.$part.':awarded'}++;
-		    $allkeys{$name.':'.$problemID.':'.$part.':code'}++;
-                    $totalProblems++;
-                }
-                $output->{$name.':'.$problemID.':NoVersion'} = 'true';
-                next;
-            }
-
-            my %partData=undef;
-            # Initialize part data, display skips correctly
-            # Skip refers to when a student made no submissions on that
-            # part/problem.
-            foreach my $part (split(/\:/,$data->{$sequence.':'.
-                                                 $problemID.
-                                                 ':parts'})) {
-                $partData{$part.':tries'}=0;
-                $partData{$part.':code'}=' ';
-                $partData{$part.':awarded'}=0;
-                $partData{$part.':timestamp'}=0;
-                foreach my $response (split(':', $data->{$sequence.':'.
-                                                         $problemID.':'.
-                                                         $part.':responseIDs'})) {
-                    $partData{$part.':'.$response.':submission'}='';
-                }
-            }
-
-            # Looping through all the versions of each part, starting with the
-            # oldest version.  Basically, it gets the most recent 
-            # set of grade data for each part.
-            my @submissions = ();
-	    for(my $Version=1; $Version<=$LatestVersion; $Version++) {
-                foreach my $part (split(/\:/,$data->{$sequence.':'.
-                                                     $problemID.
-                                                     ':parts'})) {
-
-                    if(!defined($input->{"$name:$Version:$problem".
-                                         ":resource.$part.solved"})) {
-                        # No grade for this submission, so skip
-                        next;
-                    }
-
-                    my $tries=0;
-                    my $code=' ';
-                    my $awarded=0;
-
-                    $tries = $input->{$name.':'.$Version.':'.$problem.
-                                      ':resource.'.$part.'.tries'};
-                    $awarded = $input->{$name.':'.$Version.':'.$problem.
-                                        ':resource.'.$part.'.awarded'};
-
-                    $partData{$part.':awarded'}=($awarded) ? $awarded : 0;
-                    $partData{$part.':tries'}=($tries) ? $tries : 0;
-
-                    $partData{$part.':timestamp'}=$input->{$name.':'.$Version.':'.
-                                                           $problem.
-                                                           ':timestamp'};
-                    if(!$input->{$name.':'.$Version.':'.$problem.':resource.'.$part.
-                                 '.previous'}) {
-                        foreach my $response (split(':',
-                                                   $data->{$sequence.':'.
-                                                           $problemID.':'.
-                                                           $part.':responseIDs'})) {
-                            @submissions=($input->{$name.':'.$Version.':'.
-                                                   $problem.
-                                                   ':resource.'.$part.'.'.
-                                                   $response.'.submission'},
-                                          @submissions);
-                        }
-                    }
-
-                    my $val = $input->{$name.':'.$Version.':'.$problem.
-                                       ':resource.'.$part.'.solved'};
-                    if    ($val eq 'correct_by_student')   {$code = '*';} 
-                    elsif ($val eq 'correct_by_override')  {$code = '+';}
-                    elsif ($val eq 'incorrect_attempted')  {$code = '.';} 
-                    elsif ($val eq 'incorrect_by_override'){$code = '-';}
-                    elsif ($val eq 'excused')              {$code = 'x';}
-                    elsif ($val eq 'ungraded_attempted')   {$code = '#';}
-                    else                                   {$code = ' ';}
-                    $partData{$part.':code'}=$code;
-                }
-            }
-
-            foreach my $part (split(/\:/,$data->{$sequence.':'.$problemID.
-                                                 ':parts'})) {
-                $output->{$name.':'.$problemID.':'.$part.':wrong'} = 
-                    $partData{$part.':tries'};
-		$allkeys{$name.':'.$problemID.':'.$part.':wrong'}++;
-
-                if($partData{$part.':code'} eq '*') {
-                    $output->{$name.':'.$problemID.':'.$part.':wrong'}--;
-                    $problemsCorrect++;
-                } elsif($partData{$part.':code'} eq '+') {
-                    $output->{$name.':'.$problemID.':'.$part.':wrong'}--;
-                    $problemsCorrect++;
-                }
-
-                $output->{$name.':'.$problemID.':'.$part.':tries'} = 
-                    $partData{$part.':tries'};
-                $output->{$name.':'.$problemID.':'.$part.':code'} =
-                    $partData{$part.':code'};
-                $output->{$name.':'.$problemID.':'.$part.':awarded'} =
-                    $partData{$part.':awarded'};
-		$allkeys{$name.':'.$problemID.':'.$part.':tries'}++;
-		$allkeys{$name.':'.$problemID.':'.$part.':code'}++;
-		$allkeys{$name.':'.$problemID.':'.$part.':awarded'}++;
-
-                $totalAwarded += $partData{$part.':awarded'};
-                $output->{$name.':'.$problemID.':'.$part.':timestamp'} =
-                    $partData{$part.':timestamp'};
-		$allkeys{$name.':'.$problemID.':'.$part.':timestamp'}++;
-
-                foreach my $response (split(':', $data->{$sequence.':'.
-                                                         $problemID.':'.
-                                                         $part.':responseIDs'})) {
-                    $output->{$name.':'.$problemID.':'.$part.':'.$response.
-                              ':submission'}=join(':::',@submissions);
-		    $allkeys{$name.':'.$problemID.':'.$part.':'.$response.
-			     ':submission'}++;
-                }
-
-                if($partData{$part.':code'} ne 'x') {
-                    $totalProblems++;
-                }
-            }
-        }
-
-        $output->{$name.':'.$sequence.':problemsCorrect'} = $problemsCorrect;
-	$allkeys{$name.':'.$sequence.':problemsCorrect'}++;
-        $problemsSolved += $problemsCorrect;
-	$problemsCorrect=0;
-    }
-
-    $output->{$name.':problemsSolved'} = $problemsSolved;
-    $output->{$name.':totalProblems'} = $totalProblems;
-    $output->{$name.':totalAwarded'} = $totalAwarded;
-    $allkeys{$name.':problemsSolved'}++;
-    $allkeys{$name.':totalProblems'}++;
-    $allkeys{$name.':totalAwarded'}++;
-
-    $output->{$name.':keys'} = join(':::', keys(%allkeys));
-
-    return;
-}
-
 sub LoadDiscussion {
     my ($courseID)=@_;
     my %Discuss=();
@@ -1149,54 +211,6 @@
     return \%Discuss;
 }
 
-# ----- END PROCESSING FUNCTIONS ---------------------------------------
-
-=pod
-
-=head1 HELPER FUNCTIONS
-
-These are just a couple of functions do various odd and end 
-jobs.  There was also a couple of bulk functions added.  These are
-&DownloadStudentCourseData(), &DownloadStudentCourseDataSeparate(), and
-&CheckForResidualDownload().  These functions now act as the interface
-for downloading student course data.  The statistical modules should
-no longer make the calls to dump and download and process etc.  They
-make calls to these bulk functions to get their data.
-
-=cut
-
-# ----- HELPER FUNCTIONS -----------------------------------------------
-
-sub CheckDateStampError {
-    my ($courseData, $cache, $name)=@_;
-    if($courseData->{$name.':UpToDate'} eq 'true') {
-        $cache->{$name.':lastDownloadTime'} = 
-            $courseData->{$name.':lastDownloadTime'};
-        if($courseData->{$name.':lastDownloadTime'} eq 'Not downloaded') {
-            $cache->{$name.':updateTime'} = ' Not updated';
-        } else {
-            $cache->{$name.':updateTime'}=
-                localtime($courseData->{$name.':lastDownloadTime'});
-        }
-        return 0;
-    }
-
-    $cache->{$name.':lastDownloadTime'}=$courseData->{$name.':lastDownloadTime'};
-    if($courseData->{$name.':lastDownloadTime'} eq 'Not downloaded') {
-        $cache->{$name.':updateTime'} = ' Not updated';
-    } else {
-        $cache->{$name.':updateTime'}=
-            localtime($courseData->{$name.':lastDownloadTime'});
-    }
-
-    if(defined($courseData->{$name.':error'})) {
-        $cache->{$name.':error'}=$courseData->{$name.':error'};
-        return 0;
-    }
-
-    return 1;
-}
-
 =pod
 
 =item &ProcessFullName()
@@ -1232,292 +246,6 @@
     return $Str;
 }
 
-=pod
-
-=item &TestCacheData()
-
-Determine if the cache database can be accessed with a tie.  It waits up to
-ten seconds before returning failure.  This function exists to help with
-the problems with stopping the data download.  When an abort occurs and the
-user quickly presses a form button and httpd child is created.  This
-child needs to wait for the other to finish (hopefully within ten seconds).
-
-=over 4
-
-Input: $ChartDB
-
-$ChartDB: The name of the cache database to be opened
-
-Output: -1, 0, 1
-
--1: Could not tie database
- 0: Use cached data
- 1: New cache database created, use that.
-
-=back
-
-=cut
-
-sub TestCacheData {
-    my ($ChartDB,$isRecalculate,$totalDelay)=@_;
-    my $isCached=-1;
-    my %testData;
-    my $tieTries=0;
-
-    if(!defined($totalDelay)) {
-        $totalDelay = 10;
-    }
-
-    if ((-e "$ChartDB") && (!$isRecalculate)) {
-	$isCached = 1;
-    } else {
-	$isCached = 0;
-    }
-
-    while($tieTries < $totalDelay) {
-        my $result=0;
-        if($isCached) {
-            $result=tie(%testData,'GDBM_File',$ChartDB,&GDBM_READER(),0640);
-        } else {
-            $result=tie(%testData,'GDBM_File',$ChartDB,&GDBM_NEWDB(),0640);
-        }
-        if($result) {
-            last;
-        }
-        $tieTries++;
-        sleep 1;
-    }
-    if($tieTries >= $totalDelay) {
-        return -1;
-    }
-
-    untie(%testData);
-
-    return $isCached;
-}
-
-sub DownloadStudentCourseData {
-    my ($students,$checkDate,$cacheDB,$extract,$status,$courseID,$r,$c)=@_;
-
-    my $title = 'LON-CAPA Statistics';
-    my $heading = 'Download and Process Course Data';
-    my $studentCount = scalar(@$students);
-
-    my $WhatIWant;
-    $WhatIWant = '(^version:|';
-    $WhatIWant .= '^\d+:.+?:(resource\.\d+\.';
-    $WhatIWant .= '(solved|tries|previous|awarded|(\d+\.submission))\s*$';#'
-    $WhatIWant .= '|timestamp)';
-    $WhatIWant .= ')';
-#    $WhatIWant = '.';
-
-    my %prog_state;
-    if($status eq 'true') {
-        %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r, $title,
-					       $heading,($#$students)+1);
-    }
-
-    foreach (@$students) {
-        my %cache;
-
-        if($c->aborted()) { return 'Aborted'; }
-
-        if($status eq 'true') {
-            &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,
-						  'last student '.$_);
-        }
-
-        my $downloadTime='Not downloaded';
-        my $needUpdate = 'false';
-        if($checkDate eq 'true'  && 
-           tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) {
-            $downloadTime = $cache{$_.':lastDownloadTime'};
-            $needUpdate = $cache{'ResourceUpdated'};
-            untie(%cache);
-        }
-
-        if($c->aborted()) { return 'Aborted'; }
-
-        if($needUpdate eq 'true') {
-            $downloadTime = 'Not downloaded';
-	}
-	my $courseData = 
-	    &DownloadCourseInformation($_, $courseID, $downloadTime, 
-				       $WhatIWant);
-	if(tie(%cache,'GDBM_File',$cacheDB,&GDBM_WRCREAT(),0640)) {
-	    foreach my $key (keys(%$courseData)) {
-		if($key =~ /^(con_lost|error|no_such_host)/i) {
-		    $courseData->{$_.':error'} = 'No course data for '.$_;
-		    last;
-		}
-	    }
-	    if($extract eq 'true') {
-		&ExtractStudentData($courseData, \%cache, \%cache, $_);
-	    } else {
-		&ProcessStudentData(\%cache, $courseData, $_);
-	    }
-	    untie(%cache);
-	} else {
-	    next;
-	}
-    }
-    if($status eq 'true') { &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state); }
-
-    return 'OK';
-}
-
-sub DownloadStudentCourseDataSeparate {
-    my ($students,$checkDate,$cacheDB,$extract,$status,$courseID,$r,$c)=@_;
-    my $residualFile = $Apache::lonnet::tmpdir.$courseID.'DownloadFile.db';
-    my $title = 'LON-CAPA Statistics';
-    my $heading = 'Download Course Data';
-
-    my $WhatIWant;
-    $WhatIWant = '(^version:|';
-    $WhatIWant .= '^\d+:.+?:(resource\.\d+\.';
-    $WhatIWant .= '(solved|tries|previous|awarded|(\d+\.submission))\s*$';#'
-    $WhatIWant .= '|timestamp)';
-    $WhatIWant .= ')';
-
-    &CheckForResidualDownload($cacheDB, 'true', 'true', $courseID, $r, $c);
-
-    my $studentCount = scalar(@$students);
-    my %prog_state;
-    if($status eq 'true') {
-        %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r, $title,
-						     $heading,($#$students)+1);
-    }
-    my $displayString='';
-    foreach (@$students) {
-        if($c->aborted()) {
-            return 'Aborted';
-        }
-
-        if($status eq 'true') {
-            &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,
-						  'last student '.$_);
-        }
-
-        my %cache;
-        my $downloadTime='Not downloaded';
-        my $needUpdate = 'false';
-        if($checkDate eq 'true'  && 
-           tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER(),0640)) {
-            $downloadTime = $cache{$_.':lastDownloadTime'};
-            $needUpdate = $cache{'ResourceUpdated'};
-            untie(%cache);
-        }
-
-        if($c->aborted()) {
-            return 'Aborted';
-        }
-
-        if($needUpdate eq 'true') {
-            $downloadTime = 'Not downloaded';
-	}
-
-        my $error = 0;
-        my $courseData = 
-            &DownloadCourseInformation($_, $courseID, $downloadTime,
-                                       $WhatIWant);
-        my %downloadData;
-        unless(tie(%downloadData,'GDBM_File',$residualFile,
-                   &GDBM_WRCREAT(),0640)) {
-            return 'Failed to tie temporary download hash.';
-        }
-        foreach my $key (keys(%$courseData)) {
-            $downloadData{$key} = $courseData->{$key};
-            if($key =~ /^(con_lost|error|no_such_host)/i) {
-                $error = 1;
-                last;
-            }
-        }
-        if($error) {
-            foreach my $deleteKey (keys(%$courseData)) {
-                delete $downloadData{$deleteKey};
-            }
-            $downloadData{$_.':error'} = 'No course data for '.$_;
-        }
-        untie(%downloadData);
-    }
-    if($status eq 'true') { &Apache::lonhtmlcommon::Close_PrgWin($r,
-							  \%prog_state); }
-
-    return &CheckForResidualDownload($cacheDB, 'true', 'true', 
-                                     $courseID, $r, $c);
-}
-
-sub CheckForResidualDownload {
-    my ($cacheDB,$extract,$status,$courseID,$r,$c)=@_;
-
-    my $residualFile = $Apache::lonnet::tmpdir.$courseID.'DownloadFile.db';
-    if(!-e $residualFile) {
-        return 'OK';
-    }
-
-    my %downloadData;
-    my %cache;
-    unless(tie(%downloadData,'GDBM_File',$residualFile,&GDBM_READER(),0640)) {
-        return 'Can not tie database for check for residual download: tempDB';
-    }
-    unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_WRCREAT(),0640)) {
-        untie(%downloadData);
-        return 'Can not tie database for check for residual download: cacheDB';
-    }
-
-    my @students=();
-    my %checkStudent;
-    my $key;
-    while(($key, undef) = each %downloadData) {
-        my @temp = split(':', $key);
-        my $student = $temp[0].':'.$temp[1];
-        if(!defined($checkStudent{$student})) {
-            $checkStudent{$student}++;
-            push(@students, $student);
-        }
-    }
-
-    my $heading = 'Process Course Data';
-    my $title = 'LON-CAPA Statistics';
-    my $studentCount = scalar(@students);
-    my %prog_state;
-    if($status eq 'true') {
-        %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r, $title,
-						      $heading,$#students+1);
-    }
-
-    my $count=1;
-    foreach my $name (@students) {
-        last if($c->aborted());
-
-        if($status eq 'true') {
-	    &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,
-						     'last student '.$name);
-        }
-
-        if($extract eq 'true') {
-            &ExtractStudentData(\%downloadData, \%cache, \%cache, $name);
-        } else {
-            &ProcessStudentData(\%cache, \%downloadData, $name);
-        }
-        $count++;
-    }
-
-    if($status eq 'true') { &Apache::lonhtmlcommon::Close_PrgWin($r,
-							   \%prog_state); }
-
-    untie(%cache);
-    untie(%downloadData);
-
-    if(!$c->aborted()) {
-        my @files = ($residualFile);
-        unlink(@files);
-    }
-
-    return 'OK';
-}
-
-
 ################################################
 ################################################
 
@@ -1677,56 +405,6 @@
 
 =pod
 
-=item &setup_table_names()
-
-input: course id
-
-output: none
-
-Sets the package variables for the MySQL table names:
-
-=over 4
-
-=item $symb_table
-
-=item $part_table
-
-=item $student_table
-
-=item $updatetime_table
-
-=item $performance_table
-
-=item $parameters_table
-
-=back
-
-=cut
-
-################################################
-################################################
-sub setup_table_names {
-    my $courseid = shift;
-    if (! defined($courseid)) {
-        $courseid = $ENV{'request.course.id'};
-    }
-    #
-    # Set up database names
-    my $base_id = $courseid;
-    $symb_table        = $base_id.'_'.'symb';
-    $part_table        = $base_id.'_'.'part';
-    $student_table     = $base_id.'_'.'student';
-    $updatetime_table  = $base_id.'_'.'updatetime';
-    $performance_table = $base_id.'_'.'performance';
-    $parameters_table  = $base_id.'_'.'parameters';
-    return;
-}
-
-################################################
-################################################
-
-=pod
-
 =item &init_dbs()
 
 Input: course id
@@ -1926,11 +604,20 @@
 ################################################
 ################################################
 
+my $have_read_part_table = 0;
 my %ids_by_part;
 my %parts_by_id;
 
 sub get_part_id {
     my ($part) = @_;
+    $part = 0 if (! defined($part));
+    if (! $have_read_part_table) {
+        my @Result = &Apache::lonmysql::get_rows($part_table);
+        foreach (@Result) {
+            $ids_by_part{$_->[1]}=$_->[0];
+        }
+        $have_read_part_table = 1;
+    }
     if (! exists($ids_by_part{$part})) {
         &Apache::lonmysql::store_row($part_table,[undef,$part]);
         undef(%ids_by_part);
@@ -1983,11 +670,19 @@
 ################################################
 ################################################
 
+my $have_read_symb_table = 0;
 my %ids_by_symb;
 my %symbs_by_id;
 
 sub get_symb_id {
     my ($symb) = @_;
+    if (! $have_read_symb_table) {
+        my @Result = &Apache::lonmysql::get_rows($symb_table);
+        foreach (@Result) {
+            $ids_by_symb{$_->[1]}=$_->[0];
+        }
+        $have_read_symb_table = 1;
+    }
     if (! exists($ids_by_symb{$symb})) {
         &Apache::lonmysql::store_row($symb_table,[undef,$symb]);
         undef(%ids_by_symb);
@@ -2040,12 +735,20 @@
 ################################################
 ################################################
 
+my $have_read_student_table = 0;
 my %ids_by_student;
 my %students_by_id;
 
 sub get_student_id {
     my ($sname,$sdom) = @_;
     my $student = $sname.':'.$sdom;
+    if (! $have_read_student_table) {
+        my @Result = &Apache::lonmysql::get_rows($student_table);
+        foreach (@Result) {
+            $ids_by_student{$_->[1]}=$_->[0];
+        }
+        $have_read_student_table = 1;
+    }
     if (! exists($ids_by_student{$student})) {
         &Apache::lonmysql::store_row($student_table,[undef,$student]);
         undef(%ids_by_student);
@@ -2146,6 +849,7 @@
     my $rows_stored;
     my $store_parameters_command  = 'INSERT INTO '.$parameters_table.
         ' VALUES '."\n";
+    my $num_parameters = 0;
     my $store_performance_command = 'INSERT INTO '.$performance_table.
         ' VALUES '."\n";
     return 'error' if (! defined($dbh));
@@ -2155,12 +859,14 @@
         my $symb_id = &get_symb_id($current_symb);
         #
         # Load data into the tables
-        while (my ($parameter,$value) = each (%$param_hash)) {
+        foreach my $parameter (keys(%$param_hash)) {
+            my $value = $param_hash->{$parameter};
             my $newstring;
-            if ($parameter !~ /(timestamp|resource\.(.*)\.(solved|tries|awarded|award|awarddetail|previous))/) {
+            if ($parameter !~ /(timestamp|resource\.(.*)\.(solved|tries|awarded|award|awarddetail|previous|weight))/) {
                 $newstring = "('".join("','",
                                        $symb_id,$student_id,
                                        $parameter,$value)."'),\n";
+                $num_parameters ++;
                 if ($newstring !~ /''/) {
                     $store_parameters_command .= $newstring;
                     $rows_stored++;
@@ -2200,17 +906,17 @@
     chop $store_performance_command;
     chop $store_performance_command;
     my $start = Time::HiRes::time;
-    $dbh->do($store_parameters_command);
+    $dbh->do($store_parameters_command) if ($num_parameters>0);
     if ($dbh->err()) {
         &Apache::lonnet::logthis(' bigass insert error:'.$dbh->errstr());
-        &Apache::lonnet::logthis('command = '.$store_performance_command);
+        &Apache::lonnet::logthis('command = '.$store_parameters_command);
         $returnstatus = 'error: unable to insert parameters into database';
         return $returnstatus,\%student_data;
     }
     $dbh->do($store_performance_command);
     if ($dbh->err()) {
         &Apache::lonnet::logthis(' bigass insert error:'.$dbh->errstr());
-        &Apache::lonnet::logthis('command = '.$store_parameters_command);
+        &Apache::lonnet::logthis('command = '.$store_performance_command);
         $returnstatus = 'error: unable to insert performance into database';
         return $returnstatus,\%student_data;
     }
@@ -2247,6 +953,9 @@
     my ($sname,$sdom,$courseid) = @_;
     my $status = 'okay';   # return value
     #
+    $courseid = $ENV{'request.course.id'} if (! defined($courseid));
+    # 
+    # Clean out package variables
     &setup_table_names($courseid);
     #
     # if the tables do not exist, make them
@@ -2322,7 +1031,7 @@
 sub get_student_data_from_performance_cache {
     my ($sname,$sdom,$symb,$courseid)=@_;
     my $student = $sname.':'.$sdom if (defined($sname) && defined($sdom));
-    &setup_table_names();
+    &setup_table_names($courseid);
     #
     # Return hash
     my $studentdata;
@@ -2413,20 +1122,11 @@
 ################################################
 sub get_current_state {
     my ($sname,$sdom,$symb,$courseid,$forcedownload)=@_;
-    if ($current_course ne $courseid) {
-        # Clear out variables
-        undef(%ids_by_part);
-        undef(%parts_by_id);
-        undef(%ids_by_symb);
-        undef(%symbs_by_id);
-        undef(%ids_by_student);
-        undef(%students_by_id);
-        $current_course = $courseid;
-    }
-    return () if (! defined($sname) || ! defined($sdom));
     #
     $courseid = $ENV{'request.course.id'} if (! defined($courseid));
     #
+    return () if (! defined($sname) || ! defined($sdom));
+    #
     my ($status,$data) = &ensure_current_data($sname,$sdom,$courseid);
     #
     if (defined($data)) {
@@ -2443,6 +1143,151 @@
         return %$returnhash if (defined($returnhash));
     }
     return ();
+}
+
+################################################
+################################################
+
+=pod
+
+=item &get_problem_statistics()
+
+Gather data on a given problem.  The database is assumed to be 
+populated and all local caching variables are assumed to be set
+properly.  This means you need to call &ensure_current_data for
+the students you are concerned with prior to calling this routine.
+
+Inputs: $students, $symb, $part, $courseid
+
+=cut
+
+################################################
+################################################
+sub get_problem_statistics {
+    my ($students,$symb,$part,$courseid) = @_;
+    return if (! defined($symb) || ! defined($part));
+    $courseid = $ENV{'request.course.id'} if (! defined($courseid));
+    #
+    my $symb_id = &get_symb_id($symb);
+    my $part_id = &get_part_id($part);
+    my $stats_table = $courseid.'_problem_stats';
+    #
+    &Apache::lonnet::logthis('symb id = '.$symb_id);
+    &Apache::lonnet::logthis('part id = '.$part_id);
+
+    my $dbh = &Apache::lonmysql::get_dbh();
+    return undef if (! defined($dbh));
+    &Apache::lonnet::logthis('dbh is defined');
+    #
+    # A) Number of Students attempting problem
+    # B) Total number of tries of students attempting problem
+    # C) Mod (largest number of tries for solving the problem)
+    # D) Mean (average number of tries for solving the problem)
+    # E) Number of students to solve the problem
+    # F) Number of students to solve the problem by override
+    # G) Number of students unable to solve the problem
+    # H) Degree of difficulty : 1-(E+F)/B
+    # I) Standard deviation of number of tries
+    # J) Skew of tries: sqrt(sum(Xi-D)^3)/A
+    #
+    $dbh->do('DROP TABLE '.$stats_table);  # May return an error
+    my $request = 
+        'CREATE TEMPORARY TABLE '.$stats_table.
+            ' SELECT student_id,solved,award,tries FROM '.$performance_table.
+                ' WHERE symb_id='.$symb_id.' AND part_id='.$part_id;
+#    &Apache::lonnet::logthis($request);
+    $dbh->do($request);
+    my ($num,$tries,$mod,$mean,$STD) = &execute_SQL_request
+        ($dbh,
+         'SELECT COUNT(*),SUM(tries),MAX(tries),AVG(tries),STD(tries) FROM '.
+         $stats_table);
+    my ($Solved) = &execute_SQL_request($dbh,'SELECT COUNT(tries) FROM '.
+                                        $stats_table.
+                                        " WHERE solved='correct_by_student'");
+    my ($solved) = &execute_SQL_request($dbh,'SELECT COUNT(tries) FROM '.
+                                        $stats_table.
+                                        " WHERE solved='correct_by_override'");
+    $num    = 0 if (! defined($num));
+    $tries  = 0 if (! defined($tries));
+    $mod    = 0 if (! defined($mod));
+    $STD    = 0 if (! defined($STD));
+    $Solved = 0 if (! defined($Solved));
+    $solved = 0 if (! defined($solved));
+    #
+    my $DegOfDiff = 'nan';
+    $DegOfDiff = 1-($Solved + $solved)/$tries if ($tries>0);
+
+    my $SKEW = 'nan';
+    if ($num > 0) {
+        ($SKEW) = &execute_SQL_request($dbh,'SELECT SQRT(SUM('.
+                                     'POWER(tries - '.$STD.',3)'.
+                                     '))/'.$num.' FROM '.$stats_table);
+    }
+    #
+    $dbh->do('DROP TABLE '.$stats_table);  # May return an error
+    return ($num,$tries,$mod,$mean,$Solved,$solved,$DegOfDiff,$STD,$SKEW);
+}
+
+sub execute_SQL_request {
+    my ($dbh,$request)=@_;
+#    &Apache::lonnet::logthis($request);
+    my $sth = $dbh->prepare($request);
+    $sth->execute();
+    my $row = $sth->fetchrow_arrayref();
+    if (ref($row) eq 'ARRAY' && scalar(@$row)>0) {
+        return @$row;
+    }
+    return ();
+}
+
+
+################################################
+################################################
+
+=pod
+
+=item &setup_table_names()
+
+input: course id
+
+output: none
+
+Cleans up the package variables for local caching.
+
+=cut
+
+################################################
+################################################
+sub setup_table_names {
+    my ($courseid) = @_;
+    if (! defined($courseid)) {
+        $courseid = $ENV{'request.course.id'};
+    }
+    #
+    if (! defined($current_course) || $current_course ne $courseid) {
+        # Clear out variables
+        $have_read_part_table = 0;
+        undef(%ids_by_part);
+        undef(%parts_by_id);
+        $have_read_symb_table = 0;
+        undef(%ids_by_symb);
+        undef(%symbs_by_id);
+        $have_read_student_table = 0;
+        undef(%ids_by_student);
+        undef(%students_by_id);
+        #
+        $current_course = $courseid;
+    }
+    #
+    # Set up database names
+    my $base_id = $courseid;
+    $symb_table        = $base_id.'_'.'symb';
+    $part_table        = $base_id.'_'.'part';
+    $student_table     = $base_id.'_'.'student';
+    $updatetime_table  = $base_id.'_'.'updatetime';
+    $performance_table = $base_id.'_'.'performance';
+    $parameters_table  = $base_id.'_'.'parameters';
+    return;
 }
 
 ################################################

--matthew1048631371--