mysql.php

很棒的在线教学系统

                $sequence = array();
                $positions = array();

                // Turn reporting off temporarily to avoid one line output per set_field
                global $db;
                $olddebug = $db->debug;
                $db->debug = false;
                echo 'Now updating '.$n.' cloze questions.';
                for ($i = 0; $i < $n; $i++) {
                    // Backup these two values before unsetting the object fields
                    $answers = $multianswers[$i]->answers; unset($multianswers[$i]->answers);
                    $pos = $multianswers[$i]->positionkey; unset($multianswers[$i]->positionkey);

                    // Needed for substituting multianswer ids with position keys in the $state->answer field
                    $positions[$multianswers[$i]->id] = $pos;

                // Create questions for all the multianswer victims
                    unset($multianswers[$i]->id);
                    $multianswers[$i]->length = 0;
                    $multianswers[$i]->questiontext = '';
                    $multianswers[$i]->stamp = make_unique_id_code();
                    $multianswers[$i]->name = addslashes($multianswers[$i]->name);
                    // $multianswers[$i]->parent is set in the query
                    // $multianswers[$i]->defaultgrade is set in the query
                    // $multianswers[$i]->qtype is set in the query
                    $id = insert_record('quiz_questions', $multianswers[$i]);
                    $success = $success && $id;
                    $sequence[$pos] = $id;

                // Update the quiz_answers table to point to these new questions
                $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz_answers SET question = '$id' WHERE id IN ($answers)", false);
                // Update the questiontype tables to point to these new questions

                    if (SHORTANSWER == $multianswers[$i]->qtype) {
                        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz_shortanswer SET question = '$id' WHERE answers = '$answers'", false);
                    } else if (MULTICHOICE == $multianswers[$i]->qtype) {
                        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz_multichoice SET question = '$id' WHERE answers = '$answers'", false);
                    } else if (NUMERICAL == $multianswers[$i]->qtype) {
                        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz_numerical SET question = '$id' WHERE answer IN ($answers)", false);
                    }

                    // Whenever we're through with the subquestions of one multianswer
                    // question we delete the old records in the multianswers table,
                    // store a new record with the sequence in the multianswers table
                    // and point $parent to the next multianswer question.
                    if (!isset($multianswers[$i+1]) || $parent != $multianswers[$i+1]->parent) {

                        // Substituting multianswer ids with position keys in the $state->answer field
                        if ($states = get_records('quiz_states', 'question', $parent)) {
                            foreach ($states as $state) {
                                $reg = array();
                                preg_match_all('/(?:^|,)([0-9]+)-([^,]*)/', $state->answer, $reg);
                                $state->answer = '';
                                $m = count($reg[1]);
                                for ($j = 0; $j < $m; $j++) {
                                    if (isset($positions[$reg[1][$j]])) {
                                        $state->answer .= $positions[$reg[1][$j]] . '-' . $reg[2][$j] . ',';
                                    } else {
                                        notify("Undefined multianswer id ({$reg[1][$j]}) used in state #{$state->id}!");
                                        $state->answer .= $j+1 . '-' . $reg[2][$j] . ',';
                                    }
                                }
                                $state->answer = rtrim($state->answer, ','); // strip trailing comma
                                $success = $success && update_record('quiz_states', $state);
                            }
                        }

                        $success = $success && delete_records('quiz_multianswers', 'question', $parent);
                        $multi = new stdClass;
                        $multi->question = $parent;
                        $multi->sequence = implode(',', $sequence);
                        $success = $success && insert_record('quiz_multianswers', $multi);

                        if (isset($multianswers[$i+1])) {
                            $parent    = $multianswers[$i+1]->parent;
                            $sequence  = array();
                            $positions = array();
                        }
                    }
                }
                $db->debug = $olddebug;
            }

            // Remove redundant fields from quiz_multianswers
            $success = $success && modify_database('', 'ALTER TABLE `prefix_quiz_multianswers` DROP `answers`');
            $success = $success && modify_database('', 'ALTER TABLE `prefix_quiz_multianswers` DROP `positionkey`');
            $success = $success && modify_database('', 'ALTER TABLE `prefix_quiz_multianswers` DROP `answertype`');
            $success = $success && modify_database('', 'ALTER TABLE `prefix_quiz_multianswers` DROP `norm`');
        }
    }

    if ($success && $oldversion < 2005052004) {
        // We need to remove some duplicate entries that may be present in some databases
        // due to a faulty restore script

        // Remove duplicate entries from quiz_numerical
        if ($dups = get_records_sql("
                SELECT question, answer, count(*) as num
                FROM {$CFG->prefix}quiz_numerical
                GROUP BY question, answer
                HAVING count(*) > 1"
            )) {
            foreach ($dups as $dup) {
                $ids = get_records_sql("
                    SELECT id, id
                    FROM {$CFG->prefix}quiz_numerical
                    WHERE question = '$dup->question'
                    AND answer = '$dup->answer'"
                );
                $skip = true;
                foreach ($ids as $id) {
                    if ($skip) {
                        $skip = false;
                    } else {
                        $success = $success && delete_records('quiz_numerical','id', $id->id);
                    }
                }
            }
        }

        // Remove duplicate entries from quiz_shortanswer
        if ($dups = get_records_sql("
                SELECT question, answers, count(*) as num
                FROM {$CFG->prefix}quiz_shortanswer
                GROUP BY question, answers
                HAVING count(*) > 1"
            )) {
            foreach ($dups as $dup) {
                $ids = get_records_sql("
                    SELECT id, id
                    FROM {$CFG->prefix}quiz_shortanswer
                    WHERE question = '$dup->question'
                    AND answers = '$dup->answers'"
                );
                $skip = true;
                foreach ($ids as $id) {
                    if ($skip) {
                        $skip = false;
                    } else {
                        $success = $success && delete_records('quiz_shortanswer','id', $id->id);
                    }
                }
            }
        }

        // Remove duplicate entries from quiz_multichoice
        if ($dups = get_records_sql("
                SELECT question, answers, count(*) as num
                FROM {$CFG->prefix}quiz_multichoice
                GROUP BY question, answers
                HAVING count(*) > 1"
            )) {
            foreach ($dups as $dup) {
                $ids = get_records_sql("
                    SELECT id, id
                    FROM {$CFG->prefix}quiz_multichoice
                    WHERE question = '$dup->question'
                    AND answers = '$dup->answers'"
                );
                $skip = true;
                foreach ($ids as $id) {
                    if ($skip) {
                        $skip = false;
                    } else {
                        $success = $success && delete_records('quiz_multichoice','id', $id->id);
                    }
                }
            }
        }
    }

    if ($success && $oldversion < 2005060300) {
        //Search all the orphan categories (those whose course doesn't exist)
        //and process them, deleting or moving them to site course - Bug 2459

        //Set debug to false
        $olddebug = $db->debug;
        $db->debug = false;

        //Iterate over all the quiz_categories records to get their course id
        if ($courses = get_records_sql ("SELECT DISTINCT course as id, course
                                         FROM {$CFG->prefix}quiz_categories")) {
            //Iterate over courses
            foreach ($courses as $course) {
                //If the course doesn't exist, orphan category found!
                //Process it with question_delete_course(). It will do all the hard work.
                if (!record_exists('course', 'id', $course->id)) {
                    require_once("$CFG->libdir/questionlib.php");
                    $success = $success && question_delete_course($course);
                }
            }
        }
        //Reset rebug to its original state
        $db->debug = $olddebug;
    }

    if ($success && $oldversion < 2005062600) {
        $success = $success && modify_database ('', "
            CREATE TABLE `prefix_quiz_essay` (
                `id` int(10) unsigned NOT NULL auto_increment,
                `question` int(10) unsigned NOT NULL default '0',
                `answer` varchar(255) NOT NULL default '',
                PRIMARY KEY  (`id`),
                KEY `question` (`question`)
           ) TYPE=MyISAM COMMENT='Options for essay questions'");
    
        $success = $success && modify_database ('', "
            CREATE TABLE `prefix_quiz_essay_states` (
              `id` int(10) unsigned NOT NULL auto_increment,
              `stateid` int(10) unsigned NOT NULL default '0',
              `graded` tinyint(4) unsigned NOT NULL default '0',
              `fraction` varchar(10) NOT NULL default '0.0',
              `response` text NOT NULL,
              PRIMARY KEY  (`id`)
            ) TYPE=MyISAM COMMENT='essay question type specific state information'");
    }

    if ($success && $oldversion < 2005070202) {
        // add new unique id to prepare the way for lesson module to have its own attempts table