--- /dev/null
+<?PHP // $Id$
+
+/// FUNCTIONS FOR DATABASE HANDLING ////////////////////////////////
+
+function execute_sql($command, $feedback=true) {
+/// Completely general function - it just runs some SQL and reports success.
+
+ global $db;
+
+ $result = $db->Execute("$command");
+
+ if ($result) {
+ if ($feedback) {
+ echo "<P><FONT COLOR=green><B>".get_string("success")."</B></FONT></P>";
+ }
+ return true;
+ } else {
+ if ($feedback) {
+ echo "<P><FONT COLOR=red><B>".get_string("error")."</B></FONT></P>";
+ }
+ return false;
+ }
+}
+
+function modify_database($sqlfile) {
+/// Assumes that the input text file consists of a number
+/// of SQL statements ENDING WITH SEMICOLONS. The semicolons
+/// MUST be the last character in a line.
+/// Lines that are blank or that start with "#" are ignored.
+/// Only tested with mysql dump files (mysqldump -p -d moodle)
+
+ global $CFG;
+
+ if (file_exists($sqlfile)) {
+ $success = true;
+ $lines = file($sqlfile);
+ $command = "";
+
+ while ( list($i, $line) = each($lines) ) {
+ $line = chop($line);
+ $length = strlen($line);
+
+ if ($length && substr($line, 0, 1) <> "#") {
+ if (substr($line, $length-1, 1) == ";") {
+ $line = substr($line, 0, $length-1); // strip ;
+ $command .= $line;
+ $command = str_replace("prefix_", $CFG->prefix, $command); // Table prefixes
+ if (! execute_sql($command)) {
+ $success = false;
+ }
+ $command = "";
+ } else {
+ $command .= $line;
+ }
+ }
+ }
+
+ } else {
+ $success = false;
+ echo "<P>Tried to modify database, but \"$sqlfile\" doesn't exist!</P>";
+ }
+
+ return $success;
+}
+
+
+function record_exists($table, $field="", $value="", $field2="", $value2="", $field3="", $value3="") {
+/// Returns true or false depending on whether the specified record exists
+
+ global $CFG;
+
+ if ($field and $value) {
+ $select = "WHERE $field = '$value'";
+ if ($field2 and $value2) {
+ $select .= " AND $field2 = '$value2'";
+ if ($field3 and $value3) {
+ $select .= " AND $field3 = '$value3'";
+ }
+ }
+ }
+
+ return record_exists_sql("SELECT * FROM $CFG->prefix$table $select LIMIT 1");
+}
+
+
+function record_exists_sql($sql) {
+/// Returns true or false depending on whether the specified record exists
+/// The sql statement is provided as a string.
+
+ global $db;
+
+ $rs = $db->Execute($sql);
+ if (!$rs) return false;
+
+ if ( $rs->RecordCount() ) {
+ return true;
+ } else {
+ return false;
+ }
+}
+
+
+function count_records($table, $field="", $value="", $field2="", $value2="", $field3="", $value3="") {
+/// Get all the records and count them
+
+ global $CFG;
+
+ if ($field and $value) {
+ $select = "WHERE $field = '$value'";
+ if ($field2 and $value2) {
+ $select .= " AND $field2 = '$value2'";
+ if ($field3 and $value3) {
+ $select .= " AND $field3 = '$value3'";
+ }
+ }
+ }
+
+ return count_records_sql("SELECT COUNT(*) FROM $CFG->prefix$table $select");
+}
+
+function count_records_sql($sql) {
+/// Get all the records and count them
+/// The sql statement is provided as a string.
+
+ global $db;
+
+ $rs = $db->Execute("$sql");
+ if (!$rs) return 0;
+
+ return $rs->fields[0];
+}
+
+function get_record($table, $field, $value, $field2="", $value2="", $field3="", $value3="") {
+/// Get a single record as an object
+
+ global $CFG;
+
+ $select = "WHERE $field = '$value'";
+
+ if ($field2 and $value2) {
+ $select .= " AND $field2 = '$value2'";
+ if ($field3 and $value3) {
+ $select .= " AND $field3 = '$value3'";
+ }
+ }
+
+ return get_record_sql("SELECT * FROM $CFG->prefix$table $select");
+}
+
+function get_record_sql($sql) {
+/// Get a single record as an object
+/// The sql statement is provided as a string.
+
+ global $db;
+
+ $rs = $db->Execute("$sql");
+ if (!$rs) return false;
+
+ if ( $rs->RecordCount() == 1 ) {
+ return (object)$rs->fields;
+ } else {
+ return false;
+ }
+}
+
+function get_records($table, $field="", $value="", $sort="", $fields="*") {
+/// Get a number of records as an array of objects
+/// Can optionally be sorted eg "time ASC" or "time DESC"
+/// If "fields" is specified, only those fields are returned
+/// The "key" is the first column returned, eg usually "id"
+
+ global $CFG;
+
+ if ($field and $value) {
+ $select = "WHERE $field = '$value'";
+ }
+ if ($sort) {
+ $sortorder = "ORDER BY $sort";
+ }
+
+ return get_records_sql("SELECT $fields FROM $CFG->prefix$table $select $sortorder");
+}
+
+
+function get_records_list($table, $field="", $values="", $sort="", $fields="*") {
+// Get a number of records as an array of objects
+// Differs from get_records() in that the values variable
+// can be a comma-separated list of values eg "4,5,6,10"
+// Can optionally be sorted eg "time ASC" or "time DESC"
+// The "key" is the first column returned, eg usually "id"
+
+ global $CFG;
+
+ if ($field and $value) {
+ $select = "WHERE $field in ($values)";
+ }
+ if ($sort) {
+ $sortorder = "ORDER BY $sort";
+ }
+
+ return get_records_sql("SELECT $fields FROM $CFG->prefix$table $select $sortorder");
+}
+
+
+function get_records_sql($sql) {
+// Get a number of records as an array of objects
+// The "key" is the first column returned, eg usually "id"
+// The sql statement is provided as a string.
+
+ global $db;
+
+ $rs = $db->Execute("$sql");
+ if (!$rs) return false;
+
+ if ( $rs->RecordCount() > 0 ) {
+ if ($records = $rs->GetAssoc(true)) {
+ foreach ($records as $key => $record) {
+ $objects[$key] = (object) $record;
+ }
+ return $objects;
+ } else {
+ return false;
+ }
+ } else {
+ return false;
+ }
+}
+
+function get_records_sql_menu($sql) {
+// Given an SQL select, this function returns an associative
+// array of the first two columns. This is most useful in
+// combination with the choose_from_menu function to create
+// a form menu.
+
+ global $db;
+
+ $rs = $db->Execute("$sql");
+ if (!$rs) return false;
+
+ if ( $rs->RecordCount() > 0 ) {
+ while (!$rs->EOF) {
+ $menu[$rs->fields[0]] = $rs->fields[1];
+ $rs->MoveNext();
+ }
+ return $menu;
+
+ } else {
+ return false;
+ }
+}
+
+function get_field($table, $return, $field, $value) {
+/// Get a single field from a database record
+
+ global $db, $CFG;
+
+ $rs = $db->Execute("SELECT $return FROM $CFG->prefix$table WHERE $field = '$value'");
+ if (!$rs) return false;
+
+ if ( $rs->RecordCount() == 1 ) {
+ return $rs->fields["$return"];
+ } else {
+ return false;
+ }
+}
+
+function set_field($table, $newfield, $newvalue, $field, $value) {
+/// Set a single field in a database record
+
+ global $db, $CFG;
+
+ return $db->Execute("UPDATE $CFG->prefix$table SET $newfield = '$newvalue' WHERE $field = '$value'");
+}
+
+
+function delete_records($table, $field="", $value="", $field2="", $value2="", $field3="", $value3="") {
+/// Delete one or more records from a table
+
+ global $db, $CFG;
+
+ if ($field and $value) {
+ $select = "WHERE $field = '$value'";
+ if ($field2 and $value2) {
+ $select .= " AND $field2 = '$value2'";
+ if ($field3 and $value3) {
+ $select .= " AND $field3 = '$value3'";
+ }
+ }
+ }
+
+ return $db->Execute("DELETE FROM $CFG->prefix$table $select");
+}
+
+
+function insert_record($table, $dataobject, $returnid=true) {
+/// Insert a record into a table and return the "id" field if required
+/// If the return ID isn't required, then this just reports success as true/false.
+/// $dataobject is an object containing needed data
+
+ global $db, $CFG;
+
+ // Determine all the fields needed
+ if (! $columns = $db->MetaColumns("$CFG->prefix$table")) {
+ return false;
+ }
+
+ $data = (array)$dataobject;
+
+ // Pull out data matching these fields
+ foreach ($columns as $column) {
+ if ($column->name <> "id" && isset($data[$column->name]) ) {
+ $ddd[$column->name] = $data[$column->name];
+ }
+ }
+
+ // Construct SQL queries
+ if (! $numddd = count($ddd)) {
+ return false;
+ }
+
+ $count = 0;
+ $inscolumns = "";
+ $insvalues = "";
+ $select = "";
+
+ foreach ($ddd as $key => $value) {
+ $count++;
+ $inscolumns .= "$key";
+ $insvalues .= "'$value'";
+ $select .= "$key = '$value'";
+ if ($count < $numddd) {
+ $inscolumns .= ", ";
+ $insvalues .= ", ";
+ $select .= " AND ";
+ }
+ }
+
+ if (! $rs = $db->Execute("INSERT INTO $CFG->prefix$table ($inscolumns) VALUES ($insvalues)")) {
+ return false;
+ }
+
+ if ($returnid) {
+ // Pull it out again to find the id. This is the most cross-platform method.
+ if ($rs = $db->Execute("SELECT id FROM $CFG->prefix$table WHERE $select")) {
+ return $rs->fields[0];
+ } else {
+ return false;
+ }
+ } else {
+ return true;
+ }
+}
+
+
+function update_record($table, $dataobject) {
+/// Update a record in a table
+/// $dataobject is an object containing needed data
+
+ global $db, $CFG;
+
+ if (! isset($dataobject->id) ) {
+ return false;
+ }
+
+ // Determine all the fields in the table
+ if (!$columns = $db->MetaColumns("$CFG->prefix$table")) {
+ return false;
+ }
+ $data = (array)$dataobject;
+
+ // Pull out data matching these fields
+ foreach ($columns as $column) {
+ if ($column->name <> "id" && isset($data[$column->name]) ) {
+ $ddd[$column->name] = $data[$column->name];
+ }
+ }
+
+ // Construct SQL queries
+ $numddd = count($ddd);
+ $count = 0;
+ $update = "";
+
+ foreach ($ddd as $key => $value) {
+ $count++;
+ $update .= "$key = '$value'";
+ if ($count < $numddd) {
+ $update .= ", ";
+ }
+ }
+
+ if ($rs = $db->Execute("UPDATE $CFG->prefix$table SET $update WHERE id = '$dataobject->id'")) {
+ return true;
+ } else {
+ return false;
+ }
+}
+
+
+function print_object($object) {
+/// Mostly just for debugging
+
+ $array = (array)$object;
+ foreach ($array as $key => $item) {
+ echo "$key -> $item <BR>";
+ }
+}
+
+
+
+
+/// USER DATABASE ////////////////////////////////////////////////
+
+function get_user_info_from_db($field, $value) {
+/// Get a complete user record, which includes all the info
+/// in the user record, as well as membership information
+/// Suitable for setting as $USER session cookie.
+
+ global $db, $CFG;
+
+ if (!$field || !$value)
+ return false;
+
+ if (! $result = $db->Execute("SELECT * FROM {$CFG->prefix}user WHERE $field = '$value' AND deleted <> '1'")) {
+ error("Could not find any active users!");
+ }
+
+ if ( $result->RecordCount() == 1 ) {
+ $user = (object)$result->fields;
+
+ $rs = $db->Execute("SELECT course FROM {$CFG->prefix}user_students WHERE user = '$user->id' ");
+ while (!$rs->EOF) {
+ $course = $rs->fields["course"];
+ $user->student["$course"] = true;
+ $rs->MoveNext();
+ }
+
+ $rs = $db->Execute("SELECT course FROM {$CFG->prefix}user_teachers WHERE user = '$user->id' ");
+ while (!$rs->EOF) {
+ $course = $rs->fields["course"];
+ $user->teacher["$course"] = true;
+ $rs->MoveNext();
+ }
+
+ $rs = $db->Execute("SELECT * FROM {$CFG->prefix}user_admins WHERE user = '$user->id' ");
+ while (!$rs->EOF) {
+ $user->admin = true;
+ $rs->MoveNext();
+ }
+
+ if ($course = get_site()) {
+ // Everyone is always a member of the top course
+ $user->student["$course->id"] = true;
+ }
+
+ return $user;
+
+ } else {
+ return false;
+ }
+}
+
+function update_user_in_db() {
+/// Updates user record to record their last access
+
+ global $db, $USER, $REMOTE_ADDR, $CFG;
+
+ if (!isset($USER->id))
+ return false;
+
+ $timenow = time();
+ if ($db->Execute("UPDATE {$CFG->prefix}user SET lastIP='$REMOTE_ADDR', lastaccess='$timenow'
+ WHERE id = '$USER->id' ")) {
+ return true;
+ } else {
+ return false;
+ }
+}
+
+
+function adminlogin($username, $md5password) {
+/// Does this username and password specify a valid admin user?
+
+ global $CFG;
+
+ return record_exists_sql("SELECT u.id FROM {$CFG->prefix}user u, {$CFG->prefix}user_admins a
+ WHERE u.id = a.user
+ AND u.username = '$username'
+ AND u.password = '$md5password'");
+}
+
+
+function get_site () {
+/// Returns $course object of the top-level site.
+
+ if ( $course = get_record("course", "category", 0)) {
+ return $course;
+ } else {
+ return false;
+ }
+}
+
+function get_admin () {
+/// Returns $user object of the main admin user
+
+ global $CFG;
+
+ if ( $admins = get_admins() ) {
+ foreach ($admins as $admin) {
+ return $admin; // ie the first one
+ }
+ } else {
+ return false;
+ }
+}
+
+function get_admins() {
+/// Returns list of all admins
+
+ global $CFG;
+
+ return get_records_sql("SELECT u.* FROM {$CFG->prefix}user u, {$CFG->prefix}user_admins a
+ WHERE a.user = u.id
+ ORDER BY u.id ASC");
+}
+
+
+function get_teacher($courseid) {
+/// Returns $user object of the main teacher for a course
+
+ global $CFG;
+
+ if ( $teachers = get_course_teachers($courseid, "t.authority ASC")) {
+ foreach ($teachers as $teacher) {
+ if ($teacher->authority) {
+ return $teacher; // the highest authority teacher
+ }
+ }
+ } else {
+ return false;
+ }
+}
+
+function get_course_students($courseid, $sort="u.lastaccess DESC") {
+/// Returns list of all students in this course
+
+ global $CFG;
+
+ return get_records_sql("SELECT u.* FROM {$CFG->prefix}user u, {$CFG->prefix}user_students s
+ WHERE s.course = '$courseid' AND s.user = u.id AND u.deleted = '0'
+ ORDER BY $sort");
+}
+
+function get_course_teachers($courseid, $sort="t.authority ASC") {
+/// Returns list of all teachers in this course
+
+ global $CFG;
+
+ return get_records_sql("SELECT u.*,t.authority,t.role FROM {$CFG->prefix}user u, {$CFG->prefix}user_teachers t
+ WHERE t.course = '$courseid' AND t.user = u.id AND u.deleted = '0'
+ ORDER BY $sort");
+}
+
+function get_course_users($courseid, $sort="u.lastaccess DESC") {
+/// Using this method because the direct SQL just would not always work!
+
+ $teachers = get_course_teachers($courseid, $sort);
+ $students = get_course_students($courseid, $sort);
+
+ if ($teachers and $students) {
+ return array_merge($teachers, $students);
+ } else if ($teachers) {
+ return $teachers;
+ } else {
+ return $students;
+ }
+
+/// return get_records_sql("SELECT u.* FROM user u, user_students s, user_teachers t
+/// WHERE (s.course = '$courseid' AND s.user = u.id) OR
+/// (t.course = '$courseid' AND t.user = u.id)
+/// ORDER BY $sort");
+}
+
+
+
+/// MODULE FUNCTIONS /////////////////////////////////////////////////
+
+function get_coursemodule_from_instance($modulename, $instance, $courseid) {
+/// Given an instance of a module, finds the coursemodule description
+
+ global $CFG;
+
+ return get_record_sql("SELECT cm.*, m.name
+ FROM {$CFG->prefix}course_modules cm, {$CFG->prefix}modules md, {$CFG->prefix}$modulename m
+ WHERE cm.course = '$courseid' AND
+ cm.deleted = '0' AND
+ cm.instance = m.id AND
+ md.name = '$modulename' AND
+ md.id = cm.module AND
+ m.id = '$instance'");
+
+}
+
+function get_all_instances_in_course($modulename, $courseid, $sort="cw.section") {
+/// Returns an array of all the active instances of a particular
+/// module in a given course. Returns false on any errors.
+
+ global $CFG;
+
+ return get_records_sql("SELECT m.*,cw.section,cm.id as coursemodule
+ FROM {$CFG->prefix}course_modules cm, {$CFG->prefix}course_sections cw,
+ {$CFG->prefix}modules md, {$CFG->prefix}$modulename m
+ WHERE cm.course = '$courseid' AND
+ cm.instance = m.id AND
+ cm.deleted = '0' AND
+ cm.section = cw.id AND
+ md.name = '$modulename' AND
+ md.id = cm.module
+ ORDER BY $sort");
+
+}
+
+?>