diff --git a/src/api.php b/src/api.php
index 39d750d..3752803 100644
--- a/src/api.php
+++ b/src/api.php
@@ -197,7 +197,7 @@ function checkReadAccess(?int $listId = null)
     if (is_logged()) return true;
     if ($listId !== null)
     {
-        $id = $db->sq("SELECT id FROM {$db->prefix}lists WHERE id=? AND published=1", array($listId));
+        $id = $db->sq("SELECT id FROM {$db->getPrefix()}lists WHERE id=? AND published=1", array($listId));
         if ($id) return;
     }
     http_response_code(403);
@@ -221,7 +221,7 @@ function haveWriteAccess(?int $listId = null) : bool
     if ($listId !== null && $listId != -1)
     {
         $db = DBConnection::instance();
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}lists WHERE id=?", array($listId));
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}lists WHERE id=?", array($listId));
         if (!$count) return false;
     }
     return true;
diff --git a/src/export.php b/src/export.php
index d3cdca9..d01bdf8 100644
--- a/src/export.php
+++ b/src/export.php
@@ -11,7 +11,7 @@ require_once('./init.php');
 
 $listId = (int)_get('list');
 $db = DBConnection::instance();
-$listData = $db->sqa("SELECT * FROM {$db->prefix}lists WHERE id=$listId");
+$listData = $db->sqa("SELECT * FROM {$db->getPrefix()}lists WHERE id=$listId");
 if ( $listData && !is_logged() && !$listData['published'] ) {
     $extra = json_decode($listData['extra'] ?? '', true, 10, JSON_INVALID_UTF8_SUBSTITUTE);
     $feedKey = (string) ($extra['feedKey'] ?? '');
diff --git a/src/ext/backup/class.backup.php b/src/ext/backup/class.backup.php
index a8bd7e7..d5214f3 100644
--- a/src/ext/backup/class.backup.php
+++ b/src/ext/backup/class.backup.php
@@ -61,11 +61,11 @@ class Backup
         $this->level = 0;
 
 
-        $this->writeTable($db->prefix.'lists', 'lists', 'list');
-        $this->writeTable($db->prefix.'todolist', 'tasks', 'task');
-        $this->writeTable($db->prefix.'tags', 'tags', 'tag');
-        $this->writeTable($db->prefix.'tag2task', 'tag2task', 'item');
-        $this->writeTable($db->prefix.'settings', 'settings', 'item');
+        $this->writeTable($db->getTableWithPrefix('lists'), 'lists', 'list');
+        $this->writeTable($db->getTableWithPrefix('todolist'), 'tasks', 'task');
+        $this->writeTable($db->getTableWithPrefix('tags'), 'tags', 'tag');
+        $this->writeTable($db->getTableWithPrefix('tag2task'), 'tag2task', 'item');
+        $this->writeTable($db->getTableWithPrefix('settings'), 'settings', 'item');
 
 
         $this->writeClosingTag('mttdb');
diff --git a/src/ext/backup/class.check.php b/src/ext/backup/class.check.php
index 9ec520d..d37d4af 100644
--- a/src/ext/backup/class.check.php
+++ b/src/ext/backup/class.check.php
@@ -21,31 +21,31 @@ class Check
         $msg = [];
 
         // Task without list
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}todolist WHERE list_id NOT IN (SELECT id FROM {$db->prefix}lists)");
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}todolist WHERE list_id NOT IN (SELECT id FROM {$db->getPrefix()}lists)");
         if ($count) {
             $msg[] = "Tasks without list: $count";
         }
 
         // Tag without task (not a broblem)
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}tags WHERE id NOT IN (SELECT tag_id FROM {$db->prefix}tag2task)");
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}tags WHERE id NOT IN (SELECT tag_id FROM {$db->getPrefix()}tag2task)");
         if ($count) {
             $msg[] = "Tags without task: $count";
         }
 
         // tag2task no list
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}tag2task WHERE list_id NOT IN (SELECT id FROM {$db->prefix}lists)");
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}tag2task WHERE list_id NOT IN (SELECT id FROM {$db->getPrefix()}lists)");
         if ($count) {
             $msg[] = "tag2task no list: $count";
         }
 
         // tag2task no tag
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}tag2task WHERE tag_id NOT IN (SELECT id FROM {$db->prefix}tags)");
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}tag2task WHERE tag_id NOT IN (SELECT id FROM {$db->getPrefix()}tags)");
         if ($count) {
             $msg[] = "tag2task no tag: $count";
         }
 
         // tag2task no task
-        $count = $db->sq("SELECT COUNT(*) FROM {$db->prefix}tag2task WHERE task_id NOT IN (SELECT id FROM {$db->prefix}todolist)");
+        $count = $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}tag2task WHERE task_id NOT IN (SELECT id FROM {$db->getPrefix()}todolist)");
         if ($count) {
             $msg[] = "tag2task no task: $count";
         }
@@ -53,7 +53,7 @@ class Check
         $count = 0;
         $uniqTag = []; // lowerTag => [id, tag]
         $nonuniqTag = []; // id => [tag, lowerTag, uniqId, uniqTag, taskCount]
-        $q = $db->dq("SELECT id,name,COUNT(task_id) c FROM {$db->prefix}tags t LEFT JOIN {$db->prefix}tag2task tt ON t.id=tt.tag_id GROUP BY id ORDER BY id");
+        $q = $db->dq("SELECT id,name,COUNT(task_id) c FROM {$db->getPrefix()}tags t LEFT JOIN {$db->getPrefix()}tag2task tt ON t.id=tt.tag_id GROUP BY id ORDER BY id");
         while ($r = $q->fetchAssoc()) {
             $v = mb_strtolower((string)$r['name'], 'UTF-8');
             if (!isset($uniqTag[$v])) {
@@ -86,22 +86,22 @@ class Check
         $db->ex("BEGIN");
 
         // Task without list
-        $count = (int)$db->sq("SELECT COUNT(*) FROM {$db->prefix}todolist WHERE list_id NOT IN (SELECT id FROM {$db->prefix}lists)");
+        $count = (int)$db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}todolist WHERE list_id NOT IN (SELECT id FROM {$db->getPrefix()}lists)");
         if ($count > 0) {
             // Move to new list
             $listID = \DBCore::default()->createListWithName("Restored tasks");
-            $db->ex("UPDATE {$db->prefix}todolist SET list_id=? WHERE list_id NOT IN (SELECT id FROM {$db->prefix}lists)", [$listID]);
+            $db->ex("UPDATE {$db->getPrefix()}todolist SET list_id=? WHERE list_id NOT IN (SELECT id FROM {$db->getPrefix()}lists)", [$listID]);
         }
 
         //Tags
-        $db->ex("DELETE FROM {$db->prefix}tags WHERE id NOT IN (SELECT tag_id FROM {$db->prefix}tag2task)");
-        $db->ex("DELETE FROM {$db->prefix}tag2task WHERE task_id NOT IN (SELECT id FROM {$db->prefix}todolist)");
-        $db->ex("DELETE FROM {$db->prefix}tag2task WHERE tag_id NOT IN (SELECT id FROM {$db->prefix}tags)");
+        $db->ex("DELETE FROM {$db->getPrefix()}tags WHERE id NOT IN (SELECT tag_id FROM {$db->getPrefix()}tag2task)");
+        $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE task_id NOT IN (SELECT id FROM {$db->getPrefix()}todolist)");
+        $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE tag_id NOT IN (SELECT id FROM {$db->getPrefix()}tags)");
 
         //Non-unique tags replace with first unique
         $uniqTag = [];
         $replace = [];
-        $q = $db->dq("SELECT id,name FROM {$db->prefix}tags t LEFT JOIN {$db->prefix}tag2task tt ON t.id=tt.tag_id GROUP BY id ORDER BY id");
+        $q = $db->dq("SELECT id,name FROM {$db->getPrefix()}tags t LEFT JOIN {$db->getPrefix()}tag2task tt ON t.id=tt.tag_id GROUP BY id ORDER BY id");
         while ($r = $q->fetchAssoc()) {
             $v = mb_strtolower((string)$r['name'], 'UTF-8');
             if (!isset($uniqTag[$v])) {
@@ -112,9 +112,9 @@ class Check
             }
         }
         foreach ($replace as $id => $newId) {
-            $db->ex("UPDATE {$db->prefix}tag2task SET tag_id=? WHERE tag_id=?", [$newId, $id]);
+            $db->ex("UPDATE {$db->getPrefix()}tag2task SET tag_id=? WHERE tag_id=?", [$newId, $id]);
         }
-        $db->ex("DELETE FROM {$db->prefix}tags WHERE id NOT IN (SELECT tag_id FROM {$db->prefix}tag2task)");
+        $db->ex("DELETE FROM {$db->getPrefix()}tags WHERE id NOT IN (SELECT tag_id FROM {$db->getPrefix()}tag2task)");
 
 
         // TODO: tag2task no list ?
diff --git a/src/ext/backup/class.restore.php b/src/ext/backup/class.restore.php
index 94051a0..d05bcd8 100644
--- a/src/ext/backup/class.restore.php
+++ b/src/ext/backup/class.restore.php
@@ -197,11 +197,11 @@ class Restore
         $subsStr = implode(',', array_fill(0, count($fields), '?')); // ?,?,? ...
         $db = DBConnection::instance();
         try {
-            $db->ex("INSERT INTO {$db->prefix}{$table} ($fieldsStr) VALUES ($subsStr)", $values);
+            $db->ex("INSERT INTO {$db->getPrefix()}{$table} ($fieldsStr) VALUES ($subsStr)", $values);
         }
         catch (Exception $e) {
             error_log("Failed query: {$db->lastQuery}");
-            $this->lastErrorString = "Failed to add data to table '{$db->prefix}$table'. Database error (see query in error log): ". $e->getMessage();
+            $this->lastErrorString = "Failed to add data to table '{$db->getPrefix()}$table'. Database error (see query in error log): ". $e->getMessage();
             return false;
         }
         return true;
@@ -212,13 +212,13 @@ class Restore
         $db = DBConnection::instance();
         switch ($db::DBTYPE) {
             case DBConnection::DBTYPE_MYSQL:
-                $db->ex("ALTER TABLE {$db->prefix}$table AUTO_INCREMENT = ". (int)$autoinc);
+                $db->ex("ALTER TABLE {$db->getPrefix()}$table AUTO_INCREMENT = ". (int)$autoinc);
                 break;
             case DBConnection::DBTYPE_POSTGRES:
-                $db->ex("ALTER TABLE {$db->prefix}$table ALTER COLUMN id RESTART WITH ". (int)$autoinc);
+                $db->ex("ALTER TABLE {$db->getPrefix()}$table ALTER COLUMN id RESTART WITH ". (int)$autoinc);
                 break;
             case DBConnection::DBTYPE_SQLITE:
-                $db->ex("UPDATE sqlite_sequence SET seq=? WHERE name=?", [$autoinc, $db->prefix. $table]);
+                $db->ex("UPDATE sqlite_sequence SET seq=? WHERE name=?", [$autoinc, $db->getTableWithPrefix($table)]);
                 break;
             default:
                 break;
@@ -230,7 +230,7 @@ class Restore
         $db = DBConnection::instance();
         $db->ex("BEGIN");
         foreach ($this->tableItem as $a) {
-            $table = $db->prefix. $a[0];
+            $table = $db->getTableWithPrefix($a[0]);
             if ($db::DBTYPE == DBConnection::DBTYPE_POSTGRES) {
                 $db->ex("TRUNCATE TABLE $table RESTART IDENTITY");
             }
@@ -241,7 +241,7 @@ class Restore
                 $db->ex("DELETE FROM $table");
             }
         }
-        $db->ex("DELETE FROM {$db->prefix}sessions");
+        $db->ex("DELETE FROM {$db->getPrefix()}sessions");
     }
 
     private function endRestore()
diff --git a/src/ext/notifications/class.observer.php b/src/ext/notifications/class.observer.php
index 1b0db2a..6e9cc1e 100644
--- a/src/ext/notifications/class.observer.php
+++ b/src/ext/notifications/class.observer.php
@@ -36,7 +36,7 @@ class NotificationObserver implements \MTTNotificationObserverInterface
             case MTTNotification::didCreateTask:
             case MTTNotification::didCreateList:
                 // Get list name
-                $list = $db->sqa( "SELECT name FROM {$db->prefix}lists WHERE id=?", array($object['listId'] ?? 0) );
+                $list = $db->sqa( "SELECT name FROM {$db->getPrefix()}lists WHERE id=?", array($object['listId'] ?? 0) );
                 $object['listName'] = htmlspecialchars($list['name'] ?? '');
                 $this->delayedNotifications[] = [
                     'notification' => $notification,
diff --git a/src/feed.php b/src/feed.php
index 369a461..98b9076 100644
--- a/src/feed.php
+++ b/src/feed.php
@@ -14,7 +14,7 @@ $lang = Lang::instance();
 
 $listId = (int)_get('list');
 $db = DBConnection::instance();
-$listData = $db->sqa("SELECT * FROM {$db->prefix}lists WHERE id=$listId");
+$listData = $db->sqa("SELECT * FROM {$db->getPrefix()}lists WHERE id=$listId");
 if ( $listData && need_auth() && !$listData['published'] ) {
     $extra = json_decode($listData['extra'] ?? '', true, 10, JSON_INVALID_UTF8_SUBSTITUTE);
     $feedKey = (string) ($extra['feedKey'] ?? '');
diff --git a/src/includes/api/ListsController.php b/src/includes/api/ListsController.php
index 98ae2f2..e7c5395 100644
--- a/src/includes/api/ListsController.php
+++ b/src/includes/api/ListsController.php
@@ -29,7 +29,7 @@ class ListsController extends ApiController {
             $t['total'] = 1;
         }
         $t['time'] = time();
-        $q = $db->dq("SELECT * FROM {$db->prefix}lists $sqlWhere ORDER BY ow ASC, id ASC");
+        $q = $db->dq("SELECT * FROM {$db->getPrefix()}lists $sqlWhere ORDER BY ow ASC, id ASC");
         while ($r = $q->fetchAssoc())
         {
             $t['total']++;
@@ -84,7 +84,7 @@ class ListsController extends ApiController {
     {
         checkReadAccess($id);
         $db = DBConnection::instance();
-        $r = $db->sqa( "SELECT * FROM {$db->prefix}lists WHERE id=?", array($id) );
+        $r = $db->sqa( "SELECT * FROM {$db->getPrefix()}lists WHERE id=?", array($id) );
         if (!$r) {
             $this->response->data = null;
             return;
@@ -203,7 +203,7 @@ class ListsController extends ApiController {
         }
         $db = DBConnection::instance();
         $t['total'] = 1;
-        $r = $db->sqa("SELECT * FROM {$db->prefix}lists WHERE id=$id");
+        $r = $db->sqa("SELECT * FROM {$db->getPrefix()}lists WHERE id=$id");
         $oo = $this->prepareList($r, true);
         MTTNotificationCenter::postNotification(MTTNotification::didCreateList, $oo);
         $t['list'][] = $oo;
@@ -218,9 +218,9 @@ class ListsController extends ApiController {
         $name = trim($this->req->jsonBody['name'] ?? '');
         if ($name == '')
             return $t;
-        $db->dq("UPDATE {$db->prefix}lists SET name=?,d_edited=? WHERE id=$id", array($name, time()) );
+        $db->dq("UPDATE {$db->getPrefix()}lists SET name=?,d_edited=? WHERE id=$id", array($name, time()) );
         $t['total'] = $db->affected();
-        $r = $db->sqa("SELECT * FROM {$db->prefix}lists WHERE id=$id");
+        $r = $db->sqa("SELECT * FROM {$db->getPrefix()}lists WHERE id=$id");
         $t['list'][] = $this->prepareList($r, true);
         return $t;
     }
@@ -244,7 +244,7 @@ class ListsController extends ApiController {
             Config::saveDomain('alltasks.json', $opts);
         }
         else {
-            $db->ex("UPDATE {$db->prefix}lists SET sorting=$sort,d_edited=? WHERE id=$listId", array(time()));
+            $db->ex("UPDATE {$db->getPrefix()}lists SET sorting=$sort,d_edited=? WHERE id=$listId", array(time()));
         }
     }
 
@@ -258,7 +258,7 @@ class ListsController extends ApiController {
         }
         else {
             $bitwise = $showCompleted ? 'taskview | 1' : 'taskview & ~1';
-            $db->dq("UPDATE {$db->prefix}lists SET taskview=$bitwise WHERE id=?", [$listId]);
+            $db->dq("UPDATE {$db->getPrefix()}lists SET taskview=$bitwise WHERE id=?", [$listId]);
         }
     }
 
@@ -266,7 +266,7 @@ class ListsController extends ApiController {
     {
         $db = DBConnection::instance();
         $publish = (int)($this->req->jsonBody['publish'] ?? 0);
-        $db->ex("UPDATE {$db->prefix}lists SET published=?,d_edited=? WHERE id=$listId", array($publish ? 1 : 0, time()));
+        $db->ex("UPDATE {$db->getPrefix()}lists SET published=?,d_edited=? WHERE id=$listId", array($publish ? 1 : 0, time()));
         return ['total'=>1];
     }
 
@@ -274,7 +274,7 @@ class ListsController extends ApiController {
     {
         $db = DBConnection::instance();
         $flag = (int)($this->req->jsonBody['enable'] ?? 0);
-        $json = $db->sq("SELECT extra FROM {$db->prefix}lists WHERE id=$listId") ?? '';
+        $json = $db->sq("SELECT extra FROM {$db->getPrefix()}lists WHERE id=$listId") ?? '';
         $extra = strlen($json) > 0 ? json_decode($json, true, 10, JSON_INVALID_UTF8_SUBSTITUTE) : [];
         if ($extra === false) {
             error_log("Failed to decodes JSON data of list extra listId=$listId: " . json_last_error_msg());
@@ -287,7 +287,7 @@ class ListsController extends ApiController {
             $extra['feedKey'] = randomString();
         }
         $json = json_encode($extra, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
-        $db->ex("UPDATE {$db->prefix}lists SET extra=?,d_edited=? WHERE id=$listId", array($json, time()));
+        $db->ex("UPDATE {$db->getPrefix()}lists SET extra=?,d_edited=? WHERE id=$listId", array($json, time()));
         return [
             'total' => 1,
             'list' => [[
@@ -302,7 +302,7 @@ class ListsController extends ApiController {
         $db = DBConnection::instance();
         $flag = (int)($this->req->jsonBody['shownotes'] ?? 0);
         $bitwise = ($flag == 0) ? 'taskview & ~2' : 'taskview | 2';
-        $db->dq("UPDATE {$db->prefix}lists SET taskview=$bitwise WHERE id=$listId");
+        $db->dq("UPDATE {$db->getPrefix()}lists SET taskview=$bitwise WHERE id=$listId");
         return ['total'=>1];
     }
 
@@ -317,7 +317,7 @@ class ListsController extends ApiController {
         }
         else {
             $bitwise = ($flag == 0) ? 'taskview & ~4' : 'taskview | 4';
-            $db->dq("UPDATE {$db->prefix}lists SET taskview=$bitwise WHERE id=$listId");
+            $db->dq("UPDATE {$db->getPrefix()}lists SET taskview=$bitwise WHERE id=$listId");
         }
         return ['total'=>1];
     }
@@ -328,8 +328,8 @@ class ListsController extends ApiController {
         $t = array();
         $t['total'] = 0;
         $db->ex("BEGIN");
-        $db->ex("DELETE FROM {$db->prefix}tag2task WHERE task_id IN (SELECT id FROM {$db->prefix}todolist WHERE list_id=? and compl=1)", array($listId));
-        $db->ex("DELETE FROM {$db->prefix}todolist WHERE list_id=$listId and compl=1");
+        $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE task_id IN (SELECT id FROM {$db->getPrefix()}todolist WHERE list_id=? and compl=1)", array($listId));
+        $db->ex("DELETE FROM {$db->getPrefix()}todolist WHERE list_id=$listId and compl=1");
         $t['total'] = $db->affected();
         $db->ex("COMMIT");
         if (MTTNotificationCenter::hasObserversForNotification(MTTNotification::didDeleteCompletedInList)) {
@@ -360,7 +360,7 @@ class ListsController extends ApiController {
             $setCase .= "WHEN id=$id THEN $i\n";
         }
         $ids = implode(',', $a);
-        $db->dq("UPDATE {$db->prefix}lists SET d_edited=?, ow = CASE\n $setCase END WHERE id IN ($ids)",
+        $db->dq("UPDATE {$db->getPrefix()}lists SET d_edited=?, ow = CASE\n $setCase END WHERE id IN ($ids)",
                     array(time()) );
         $t['total'] = 1;
         return $t;
@@ -377,11 +377,11 @@ class ListsController extends ApiController {
             $list = $this->getListRowById($id);
         }
         $db->ex("BEGIN");
-        $db->ex("DELETE FROM {$db->prefix}lists WHERE id=$id");
+        $db->ex("DELETE FROM {$db->getPrefix()}lists WHERE id=$id");
         $t['total'] = $db->affected();
         if ($t['total']) {
-            $db->ex("DELETE FROM {$db->prefix}tag2task WHERE list_id=$id");
-            $db->ex("DELETE FROM {$db->prefix}todolist WHERE list_id=$id");
+            $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE list_id=$id");
+            $db->ex("DELETE FROM {$db->getPrefix()}todolist WHERE list_id=$id");
         }
         $db->ex("COMMIT");
         if ($t['total'] && MTTNotificationCenter::hasObserversForNotification(MTTNotification::didDeleteList)) {
diff --git a/src/includes/api/TagsController.php b/src/includes/api/TagsController.php
index cbf9f6f..5f66765 100644
--- a/src/includes/api/TagsController.php
+++ b/src/includes/api/TagsController.php
@@ -21,7 +21,7 @@ class TagsController extends ApiController {
 
         $sqlWhere = ($listId == -1) ? "" : "WHERE list_id = $listId";
         $q = $db->dq("SELECT name, tag_id, COUNT(tag_id) AS tags_count
-                      FROM {$db->prefix}tag2task INNER JOIN {$db->prefix}tags ON tag_id = id
+                      FROM {$db->getPrefix()}tag2task INNER JOIN {$db->getPrefix()}tags ON tag_id = id
                       $sqlWhere
                       GROUP BY tag_id, name
                       ORDER BY tags_count DESC");
@@ -73,8 +73,8 @@ class TagsController extends ApiController {
         $db = DBConnection::instance();
         $begin = trim(_get('q'));
         $limit = 8;
-        $q = $db->dq("SELECT name, tag_id AS id FROM {$db->prefix}tags
-                      INNER JOIN {$db->prefix}tag2task ON id=tag_id
+        $q = $db->dq("SELECT name, tag_id AS id FROM {$db->getPrefix()}tags
+                      INNER JOIN {$db->getPrefix()}tag2task ON id=tag_id
                       WHERE list_id=$listId AND ". $db->like('name', '%s%%', $begin). "
                       GROUP BY tag_id, name
                       ORDER BY name
diff --git a/src/includes/api/TasksController.php b/src/includes/api/TasksController.php
index c54d7f9..f83ef20 100644
--- a/src/includes/api/TasksController.php
+++ b/src/includes/api/TasksController.php
@@ -75,15 +75,15 @@ class TasksController extends ApiController {
             if (count($tagIds) > 0) {
                 $tagAnd = [];
                 foreach ($tagIds as $ids) {
-                    $tagAnd[] = "task_id IN (SELECT task_id FROM {$db->prefix}tag2task WHERE tag_id IN (". implode(',', $ids). "))";
+                    $tagAnd[] = "task_id IN (SELECT task_id FROM {$db->getPrefix()}tag2task WHERE tag_id IN (". implode(',', $ids). "))";
                 }
                 $sqlWhere .= "\n AND todo.id IN (".
-                             "SELECT DISTINCT task_id FROM {$db->prefix}tag2task WHERE ". implode(' AND ', $tagAnd). ")";
+                             "SELECT DISTINCT task_id FROM {$db->getPrefix()}tag2task WHERE ". implode(' AND ', $tagAnd). ")";
             }
 
             // Exclude tags
             if (count($tagExIds) > 0) {
-                $sqlWhere .= "\n AND todo.id NOT IN (SELECT DISTINCT task_id FROM {$db->prefix}tag2task ".
+                $sqlWhere .= "\n AND todo.id NOT IN (SELECT DISTINCT task_id FROM {$db->getPrefix()}tag2task ".
                             "WHERE tag_id IN (". implode(',', $tagExIds). "))";
             }
         }
@@ -132,9 +132,9 @@ class TasksController extends ApiController {
 
         $q = $db->dq("
             SELECT todo.*, todo.duedate IS NULL AS ddn, $groupConcat
-            FROM {$db->prefix}todolist AS todo
-            LEFT JOIN {$db->prefix}tag2task AS t2t ON todo.id = t2t.task_id
-            LEFT JOIN {$db->prefix}tags AS tags ON t2t.tag_id = tags.id
+            FROM {$db->getPrefix()}todolist AS todo
+            LEFT JOIN {$db->getPrefix()}tag2task AS t2t ON todo.id = t2t.task_id
+            LEFT JOIN {$db->getPrefix()}tags AS tags ON t2t.tag_id = tags.id
             WHERE $sqlWhereListId $sqlWhere
             GROUP BY todo.id   $sqlHaving
             $sqlSort
@@ -295,7 +295,7 @@ class TasksController extends ApiController {
 
         if ($sqlWhereList) {
             $sqlWhere = implode(' OR ', $sqlWhereList);
-            $q = $db->dq("SELECT list_id, COUNT(id) c FROM {$db->prefix}todolist
+            $q = $db->dq("SELECT list_id, COUNT(id) c FROM {$db->getPrefix()}todolist
                           WHERE $sqlWhere GROUP BY list_id");
             while ($r = $q->fetchAssoc()) {
                 $a[] = [
@@ -309,7 +309,7 @@ class TasksController extends ApiController {
         $list = (int) ($this->req->jsonBody['list'] ?? 0);
         $later = (int) ($this->req->jsonBody['later'] ?? 0);
         if ($list > 0 && $later > 0 && (!$userLists || in_array((string)$list, $userLists))) {
-            $q = $db->dq("SELECT id FROM {$db->prefix}todolist
+            $q = $db->dq("SELECT id FROM {$db->getPrefix()}todolist
                           WHERE list_id = $list AND compl=0 AND d_created > $later");
             while ($r = $q->fetchAssoc()) {
                 $b[] = (int)$r['id'];
@@ -355,10 +355,10 @@ class TasksController extends ApiController {
         if (Config::get('autotag')) {
             $tags .= ',' . ($this->req->jsonBody['tag'] ?? '');
         }
-        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}todolist WHERE list_id=$listId AND compl=0");
+        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}todolist WHERE list_id=$listId AND compl=0");
         $date = time();
         $db->ex("BEGIN");
-        $db->dq("INSERT INTO {$db->prefix}todolist (uuid,list_id,title,d_created,d_edited,ow,prio,duedate) VALUES (?,?,?,?,?,?,?,?)",
+        $db->dq("INSERT INTO {$db->getPrefix()}todolist (uuid,list_id,title,d_created,d_edited,ow,prio,duedate) VALUES (?,?,?,?,?,?,?,?)",
                     array(generateUUID(), $listId, $title, $date, $date, $ow, $prio, $duedate) );
         $id = (int) $db->lastInsertId();
         if ($tags != '')
@@ -393,10 +393,10 @@ class TasksController extends ApiController {
         $tags = $this->req->jsonBody['tags'] ?? '';
         if (Config::get('autotag'))
             $tags .= ',' . ($this->req->jsonBody['tag'] ?? '');
-        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}todolist WHERE list_id=$listId AND compl=0");
+        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}todolist WHERE list_id=$listId AND compl=0");
         $date = time();
         $db->ex("BEGIN");
-        $db->dq("INSERT INTO {$db->prefix}todolist (uuid,list_id,title,d_created,d_edited,ow,prio,note,duedate) VALUES (?,?,?,?,?,?,?,?,?)",
+        $db->dq("INSERT INTO {$db->getPrefix()}todolist (uuid,list_id,title,d_created,d_edited,ow,prio,note,duedate) VALUES (?,?,?,?,?,?,?,?,?)",
                     array(generateUUID(), $listId, $title, $date, $date, $ow, $prio, $note, $duedate) );
         $id = (int) $db->lastInsertId();
         if ($tags != '')
@@ -428,15 +428,15 @@ class TasksController extends ApiController {
         if ($title == '') {
             return $t;
         }
-        $listId = (int) $db->sq("SELECT list_id FROM {$db->prefix}todolist WHERE id=$id");
+        $listId = (int) $db->sq("SELECT list_id FROM {$db->getPrefix()}todolist WHERE id=$id");
         $tags = trim( $this->req->jsonBody['tags'] ?? '' );
         $db->ex("BEGIN");
-        $db->ex("DELETE FROM {$db->prefix}tag2task WHERE task_id=$id");
+        $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE task_id=$id");
         $aTags = $this->prepareTags($tags);
         if ($aTags) {
             $this->addTaskTags($id, $aTags['ids'], $listId);
         }
-        $db->dq("UPDATE {$db->prefix}todolist SET title=?,note=?,prio=?,duedate=?,d_edited=? WHERE id=$id",
+        $db->dq("UPDATE {$db->getPrefix()}todolist SET title=?,note=?,prio=?,duedate=?,d_edited=? WHERE id=$id",
                 array($title, $note, $prio, $duedate, time()) );
         $db->ex("COMMIT");
         $task = $this->getTaskRowById($id, true);
@@ -477,21 +477,21 @@ class TasksController extends ApiController {
         $db = DBConnection::instance();
 
         // Check task exists and not in target list
-        $r = $db->sqa("SELECT * FROM {$db->prefix}todolist WHERE id=?", array($id));
+        $r = $db->sqa("SELECT * FROM {$db->getPrefix()}todolist WHERE id=?", array($id));
         if (!$r || $listId == $r['list_id'])
             return false;
 
         // Check target list exists
-        $l = $db->sqa("SELECT id,name FROM {$db->prefix}lists WHERE id=?", [$listId]);
+        $l = $db->sqa("SELECT id,name FROM {$db->getPrefix()}lists WHERE id=?", [$listId]);
         if (!$l)
             return false;
         $listName = $l['name'];
 
-        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}todolist WHERE list_id=? AND compl=?", array($listId, $r['compl']?1:0));
+        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}todolist WHERE list_id=? AND compl=?", array($listId, $r['compl']?1:0));
 
         $db->ex("BEGIN");
-        $db->ex("UPDATE {$db->prefix}tag2task SET list_id=? WHERE task_id=?", array($listId, $id));
-        $db->dq("UPDATE {$db->prefix}todolist SET list_id=?, ow=?, d_edited=? WHERE id=?", array($listId, $ow, time(), $id));
+        $db->ex("UPDATE {$db->getPrefix()}tag2task SET list_id=? WHERE task_id=?", array($listId, $id));
+        $db->dq("UPDATE {$db->getPrefix()}todolist SET list_id=?, ow=?, d_edited=? WHERE id=?", array($listId, $ow, time(), $id));
         $db->ex("COMMIT");
         return true;
     }
@@ -500,12 +500,12 @@ class TasksController extends ApiController {
     {
         $db = DBConnection::instance();
         $compl = (int)($this->req->jsonBody['compl'] ?? 0);
-        $listId = (int)$db->sq("SELECT list_id FROM {$db->prefix}todolist WHERE id=$id");
-        if ($compl) $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}todolist WHERE list_id=$listId AND compl=1");
-        else $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}todolist WHERE list_id=$listId AND compl=0");
+        $listId = (int)$db->sq("SELECT list_id FROM {$db->getPrefix()}todolist WHERE id=$id");
+        if ($compl) $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}todolist WHERE list_id=$listId AND compl=1");
+        else $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}todolist WHERE list_id=$listId AND compl=0");
         $date = time();
         $dateCompleted = $compl ? $date : 0;
-        $db->dq("UPDATE {$db->prefix}todolist SET compl=$compl,ow=$ow,d_completed=?,d_edited=? WHERE id=$id",
+        $db->dq("UPDATE {$db->getPrefix()}todolist SET compl=$compl,ow=$ow,d_completed=?,d_edited=? WHERE id=$id",
                     array($dateCompleted, $date) );
         $task = $this->getTaskRowById($id);
         MTTNotificationCenter::postNotification(MTTNotification::didCompleteTask, $task);
@@ -520,7 +520,7 @@ class TasksController extends ApiController {
         $db = DBConnection::instance();
         $note = $this->req->jsonBody['note'] ?? '';
         $note = str_replace("\r\n", "\n", $note);
-        $db->dq("UPDATE {$db->prefix}todolist SET note=?,d_edited=? WHERE id=$id", array($note, time()) );
+        $db->dq("UPDATE {$db->getPrefix()}todolist SET note=?,d_edited=? WHERE id=$id", array($note, time()) );
         if (MTTNotificationCenter::hasObserversForNotification(MTTNotification::didEditTask)) {
             $task = $this->getTaskRowById($id);
             MTTNotificationCenter::postNotification(MTTNotification::didEditTask, [
@@ -540,7 +540,7 @@ class TasksController extends ApiController {
         $prio = (int)($this->req->jsonBody['prio'] ?? 0);
         if ($prio < -1) $prio = -1;
         elseif ($prio > 2) $prio = 2;
-        $db->ex("UPDATE {$db->prefix}todolist SET prio=$prio,d_edited=? WHERE id=$id", array(time()) );
+        $db->ex("UPDATE {$db->getPrefix()}todolist SET prio=$prio,d_edited=? WHERE id=$id", array(time()) );
         if (MTTNotificationCenter::hasObserversForNotification(MTTNotification::didEditTask)) {
             $task = $this->getTaskRowById($id);
             MTTNotificationCenter::postNotification(MTTNotification::didEditTask, [
@@ -573,7 +573,7 @@ class TasksController extends ApiController {
             foreach ($ad as $diff=>$ids) {
                 if ($diff >=0) $set = "ow=ow+".$diff;
                 else $set = "ow=ow-".abs($diff);
-                $db->dq("UPDATE {$db->prefix}todolist SET $set,d_edited=? WHERE id IN (".implode(',',$ids).")", array(time()) );
+                $db->dq("UPDATE {$db->getPrefix()}todolist SET $set,d_edited=? WHERE id IN (".implode(',',$ids).")", array(time()) );
             }
             $db->ex("COMMIT");
             $t['total'] = 1;
@@ -590,9 +590,9 @@ class TasksController extends ApiController {
         }
         $db = DBConnection::instance();
         $db->ex("BEGIN");
-        $db->ex("DELETE FROM {$db->prefix}tag2task WHERE task_id=$id");
+        $db->ex("DELETE FROM {$db->getPrefix()}tag2task WHERE task_id=$id");
         //TODO: delete unused tags?
-        $db->dq("DELETE FROM {$db->prefix}todolist WHERE id=$id");
+        $db->dq("DELETE FROM {$db->getPrefix()}todolist WHERE id=$id");
         $deleted = $db->affected();
         $db->ex("COMMIT");
         if ($deleted && MTTNotificationCenter::hasObserversForNotification(MTTNotification::didDeleteTask)) {
@@ -612,7 +612,7 @@ class TasksController extends ApiController {
             $sqlWhere = "WHERE published=1";
         }
         $a = array();
-        $q = $db->dq("SELECT id,name FROM {$db->prefix}lists $sqlWhere ORDER BY id ASC");
+        $q = $db->dq("SELECT id,name FROM {$db->getPrefix()}lists $sqlWhere ORDER BY id ASC");
         while($r = $q->fetchRow()) {
             $a[ (string)$r[0] ] = (string)$r[1];
         }
@@ -770,18 +770,18 @@ class TasksController extends ApiController {
     private function getTagId($tag)
     {
         $db = DBConnection::instance();
-        $id = $db->sq("SELECT id FROM {$db->prefix}tags WHERE name=?", array($tag));
+        $id = $db->sq("SELECT id FROM {$db->getPrefix()}tags WHERE name=?", array($tag));
         return $id ? $id : 0;
     }
 
     private function getOrCreateTag($name): array
     {
         $db = DBConnection::instance();
-        $tagId = $db->sq("SELECT id FROM {$db->prefix}tags WHERE name=?", array($name));
+        $tagId = $db->sq("SELECT id FROM {$db->getPrefix()}tags WHERE name=?", array($name));
         if ($tagId)
             return array('id'=>$tagId, 'name'=>$name);
 
-        $db->ex("INSERT INTO {$db->prefix}tags (name) VALUES (?)", array($name));
+        $db->ex("INSERT INTO {$db->getPrefix()}tags (name) VALUES (?)", array($name));
         return array(
             'id' => $db->lastInsertId(),
             'name' => $name
@@ -814,7 +814,7 @@ class TasksController extends ApiController {
         if (!$tagIds) return;
         foreach ($tagIds as $tagId) {
             $db->ex(
-                "INSERT INTO {$db->prefix}tag2task (task_id,tag_id,list_id) VALUES (?,?,?)",
+                "INSERT INTO {$db->getPrefix()}tag2task (task_id,tag_id,list_id) VALUES (?,?,?)",
                 array($taskId, $tagId, $listId)
             );
         }
diff --git a/src/includes/class.config.php b/src/includes/class.config.php
index 2446656..a5b440f 100644
--- a/src/includes/class.config.php
+++ b/src/includes/class.config.php
@@ -227,7 +227,7 @@ class Config
     public static function requestDomain(string $key): array
     {
         $db = DBConnection::instance();
-        $json = $db->sq("SELECT param_value FROM {$db->prefix}settings WHERE param_key = ?", array($key));
+        $json = $db->sq("SELECT param_value FROM {$db->getPrefix()}settings WHERE param_key = ?", array($key));
         if (!$json) return array();
         $j = json_decode($json, true, 100, JSON_INVALID_UTF8_SUBSTITUTE);
         if ($j === null) {
@@ -263,12 +263,12 @@ class Config
             throw new Exception("Failed to create JSON object with settings. Code: ". (int)json_last_error());
         }
         $db = DBConnection::instance();
-        $keyExists = $db->sq("SELECT COUNT(param_key) FROM {$db->prefix}settings WHERE param_key = ?", array($key) );
+        $keyExists = $db->sq("SELECT COUNT(param_key) FROM {$db->getPrefix()}settings WHERE param_key = ?", array($key) );
         if ($keyExists) {
-            $db->ex("UPDATE {$db->prefix}settings SET param_value = ? WHERE param_key = ?", array($json,$key) );
+            $db->ex("UPDATE {$db->getPrefix()}settings SET param_value = ? WHERE param_key = ?", array($json,$key) );
         }
         else {
-            $db->ex("INSERT INTO {$db->prefix}settings (param_key,param_value) VALUES (?,?)", array($key,$json) );
+            $db->ex("INSERT INTO {$db->getPrefix()}settings (param_key,param_value) VALUES (?,?)", array($key,$json) );
         }
     }
 
diff --git a/src/includes/class.dbconnection.php b/src/includes/class.dbconnection.php
index 8f33262..9d300c5 100644
--- a/src/includes/class.dbconnection.php
+++ b/src/includes/class.dbconnection.php
@@ -77,6 +77,14 @@ abstract class Database_Abstract
         $this->prefix = $prefix;
     }
 
+    function getPrefix(): string {
+        return $this->prefix;
+    }
+
+    function getTableWithPrefix(string $table): string {
+        return $this->prefix . $table;
+    }
+
     function setLogQueryToFile(?string $path) {
         //any checks?
         $this->logQueryToFile = $path;
diff --git a/src/includes/class.dbcore.php b/src/includes/class.dbcore.php
index 942a58c..2fc4a72 100644
--- a/src/includes/class.dbcore.php
+++ b/src/includes/class.dbcore.php
@@ -70,7 +70,7 @@ class DBCore
     public function getListIdByTaskId(int $id): int
     {
         $db = $this->db;
-        $listId = (int)$db->sq("SELECT list_id FROM {$db->prefix}todolist WHERE id=". (int)$id);
+        $listId = (int)$db->sq("SELECT list_id FROM {$db->getPrefix()}todolist WHERE id=". (int)$id);
         return $listId;
     }
 
@@ -78,7 +78,7 @@ class DBCore
     public function getListById(int $id): ?array
     {
         $db = $this->db;
-        $r = $db->sqa("SELECT * FROM {$db->prefix}lists WHERE id=?", [$id]);
+        $r = $db->sqa("SELECT * FROM {$db->getPrefix()}lists WHERE id=?", [$id]);
         return $r;
     }
 
@@ -86,7 +86,7 @@ class DBCore
     public function taskExists(int $id): bool
     {
         $db = $this->db;
-        $count = (int) $db->sq("SELECT COUNT(*) FROM {$db->prefix}todolist WHERE id = $id");
+        $count = (int) $db->sq("SELECT COUNT(*) FROM {$db->getPrefix()}todolist WHERE id = $id");
         return ($count > 0) ? true : false;
     }
 
@@ -103,9 +103,9 @@ class DBCore
         }
         $r = $db->sqa("
             SELECT todo.*, $groupConcat
-            FROM {$db->prefix}todolist AS todo
-            LEFT JOIN {$db->prefix}tag2task AS t2t ON todo.id = t2t.task_id
-            LEFT JOIN {$db->prefix}tags AS tags ON t2t.tag_id = tags.id
+            FROM {$db->getPrefix()}todolist AS todo
+            LEFT JOIN {$db->getPrefix()}tag2task AS t2t ON todo.id = t2t.task_id
+            LEFT JOIN {$db->getPrefix()}tags AS tags ON t2t.tag_id = tags.id
             WHERE todo.id = $id
             GROUP BY todo.id
         ");
@@ -156,9 +156,9 @@ class DBCore
 
         $q = $db->dq("
             SELECT todo.*, todo.duedate IS NULL AS ddn, GROUP_CONCAT(tags.id) AS tags_ids, GROUP_CONCAT(tags.name) AS tags
-            FROM {$db->prefix}todolist AS todo
-            LEFT JOIN {$db->prefix}tag2task AS t2t ON todo.id = t2t.task_id
-            LEFT JOIN {$db->prefix}tags AS tags ON t2t.tag_id = tags.id
+            FROM {$db->getPrefix()}todolist AS todo
+            LEFT JOIN {$db->getPrefix()}tag2task AS t2t ON todo.id = t2t.task_id
+            LEFT JOIN {$db->getPrefix()}tags AS tags ON t2t.tag_id = tags.id
             WHERE todo.list_id = $listId  $sqlWhere
             GROUP BY todo.id
             $sqlSort
@@ -179,9 +179,9 @@ class DBCore
         if ($name == '') {
             return null;
         }
-        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->prefix}lists");
+        $ow = 1 + (int)$db->sq("SELECT MAX(ow) FROM {$db->getPrefix()}lists");
         $time = time();
-        $db->dq("INSERT INTO {$db->prefix}lists (uuid,name,ow,d_created,d_edited,taskview) VALUES (?,?,?,?,?,?)",
+        $db->dq("INSERT INTO {$db->getPrefix()}lists (uuid,name,ow,d_created,d_edited,taskview) VALUES (?,?,?,?,?,?)",
                     array(generateUUID(), $name, $ow, $time, $time, 1) );
         $id = $db->lastInsertId();
         return (int)$id;
@@ -196,7 +196,7 @@ class DBCore
     function getTagIdsByName(string $name): array
     {
         $db = DBConnection::instance();
-        $q = $db->dq("SELECT id FROM {$db->prefix}tags WHERE ". $db->ciEquals('name', $name));
+        $q = $db->dq("SELECT id FROM {$db->getPrefix()}tags WHERE ". $db->ciEquals('name', $name));
         $a = [];
         while ($r = $q->fetchAssoc()) {
             $a[] = (int) $r['id'];
diff --git a/src/includes/class.sessionhandler.php b/src/includes/class.sessionhandler.php
index 85c6c04..b92ebf0 100644
--- a/src/includes/class.sessionhandler.php
+++ b/src/includes/class.sessionhandler.php
@@ -45,7 +45,7 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
     {
         // read session data if not expired
         $time = time();
-        $r = $this->db->sq("SELECT data,last_access,expires FROM {$this->db->prefix}sessions WHERE id = ?", [$id]);
+        $r = $this->db->sq("SELECT data,last_access,expires FROM {$this->db->getPrefix()}sessions WHERE id = ?", [$id]);
         if ( is_null($r) ) {
             // We return '' instead of false to avoid warning
             return '';
@@ -59,7 +59,7 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
         // refresh every 8 hours
         if ( $r[1] + 28800 < $time ) {
             $expire = $time + 14 * 86400;
-            $this->db->ex("UPDATE {$this->db->prefix}sessions SET last_access=?,expires=? WHERE id = ?",
+            $this->db->ex("UPDATE {$this->db->getPrefix()}sessions SET last_access=?,expires=? WHERE id = ?",
                 array($time, $expire, $id) );
         }
 
@@ -84,15 +84,15 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
         $time = time();
         $expire = $time + 14 * 86400;
 
-        $exists = $this->db->sq("SELECT COUNT(*) FROM {$this->db->prefix}sessions WHERE id = ?", [$id]);
+        $exists = $this->db->sq("SELECT COUNT(*) FROM {$this->db->getPrefix()}sessions WHERE id = ?", [$id]);
         if (!$exists) {
             // Create new session with 14 days lifetime
-            $this->db->ex("INSERT INTO {$this->db->prefix}sessions (id,data,last_access,expires) VALUES (?,?,?,?)",
+            $this->db->ex("INSERT INTO {$this->db->getPrefix()}sessions (id,data,last_access,expires) VALUES (?,?,?,?)",
                 array($id, $data, $time, $expire) );
         }
         else {
             // Update existing session
-            $this->db->ex("UPDATE {$this->db->prefix}sessions SET data = ?, last_access=?, expires=? WHERE id = ?",
+            $this->db->ex("UPDATE {$this->db->getPrefix()}sessions SET data = ?, last_access=?, expires=? WHERE id = ?",
                 array($data, $time, $expire, $id) );
         }
         return true;
@@ -105,7 +105,7 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
      */
     public function destroy($id): bool
     {
-        $this->db->ex("DELETE FROM {$this->db->prefix}sessions WHERE id = ?", [$id]);
+        $this->db->ex("DELETE FROM {$this->db->getPrefix()}sessions WHERE id = ?", [$id]);
         return true;
     }
 
@@ -118,7 +118,7 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
     {
         // We ignore php runtime 'session.gc_maxlifetime'
         $expire = time();
-        $this->db->ex("DELETE FROM {$this->db->prefix}sessions WHERE expires < $expire");
+        $this->db->ex("DELETE FROM {$this->db->getPrefix()}sessions WHERE expires < $expire");
         return $this->db->affected();
     }
 
@@ -130,7 +130,7 @@ class MTTSessionHandler implements SessionHandlerInterface, SessionUpdateTimesta
      */
     public function validateId($id): bool
     {
-        $r = $this->db->sq("SELECT COUNT(*) FROM {$this->db->prefix}sessions WHERE id = ?", [$id]);
+        $r = $this->db->sq("SELECT COUNT(*) FROM {$this->db->getPrefix()}sessions WHERE id = ?", [$id]);
         if ($r)
             return true;
         return false;
diff --git a/src/init.php b/src/init.php
index fbfbd39..1ef30c3 100644
--- a/src/init.php
+++ b/src/init.php
@@ -163,7 +163,7 @@ function configureDbConnection()
     # Check tables created
     global $checkDbExists;
     if (!Config::$noDatabase && isset($checkDbExists) && $checkDbExists) {
-        $exists = $db->tableExists($db->prefix.'settings');
+        $exists = $db->tableExists($db->getTableWithPrefix('settings'));
         if (!$exists) {
             die("Need to create or update the database. Run <a href=setup.php>setup.php</a> first.");
         }
diff --git a/src/setup.php b/src/setup.php
index 63ac411..539155b 100644
--- a/src/setup.php
+++ b/src/setup.php
@@ -175,7 +175,7 @@ if ($ver == '')
         createAllTables($db, $dbtype);  # throws
 
         # create default list
-        $db->ex( "INSERT INTO {$db->prefix}lists (uuid,name,d_created,taskview) VALUES (?,?,?,?)", array(generateUUID(), 'Todo', time(), 1) );
+        $db->ex( "INSERT INTO {$db->getPrefix()}lists (uuid,name,d_created,taskview) VALUES (?,?,?,?)", array(generateUUID(), 'Todo', time(), 1) );
 
         Config::save();
     }
@@ -347,7 +347,7 @@ function createMysqlTables(Database_Abstract $db)
 
     // Mysql does not support transactions while executing DDL
     $db->ex(
-"CREATE TABLE {$db->prefix}lists (
+"CREATE TABLE {$db->getPrefix()}lists (
     `id` INT UNSIGNED NOT NULL auto_increment,
     `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '',
     `ow` INT NOT NULL default 0,
@@ -364,7 +364,7 @@ function createMysqlTables(Database_Abstract $db)
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}todolist (
+"CREATE TABLE {$db->getPrefix()}todolist (
     `id` INT UNSIGNED NOT NULL auto_increment,
     `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '',
     `list_id` INT UNSIGNED NOT NULL default 0,
@@ -384,7 +384,7 @@ function createMysqlTables(Database_Abstract $db)
 
     // Max length of varchar of utf8mb4 with UNIQUE index is 191 until Mysql 5.7 and MariaDB 10.2
     $db->ex(
-"CREATE TABLE {$db->prefix}tags (
+"CREATE TABLE {$db->getPrefix()}tags (
     `id` INT UNSIGNED NOT NULL auto_increment,
     `name` VARCHAR(250) NOT NULL default '',
     PRIMARY KEY(`id`),
@@ -393,7 +393,7 @@ function createMysqlTables(Database_Abstract $db)
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}tag2task (
+"CREATE TABLE {$db->getPrefix()}tag2task (
     `tag_id` INT UNSIGNED NOT NULL,
     `task_id` INT UNSIGNED NOT NULL,
     `list_id` INT UNSIGNED NOT NULL,
@@ -404,7 +404,7 @@ function createMysqlTables(Database_Abstract $db)
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}settings (
+"CREATE TABLE {$db->getPrefix()}settings (
     `param_key`   VARCHAR(250) CHARACTER SET latin1 NOT NULL default '',
     `param_value` TEXT,
     UNIQUE KEY `param_key` (`param_key`)
@@ -412,7 +412,7 @@ function createMysqlTables(Database_Abstract $db)
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}sessions (
+"CREATE TABLE {$db->getPrefix()}sessions (
     `id`          VARCHAR(64) CHARACTER SET latin1 NOT NULL default '',  /* upto 64 bytes for sha256 */
     `data`        TEXT,
     `last_access` INT UNSIGNED NOT NULL default 0,  /* time() timestamp */
@@ -428,7 +428,7 @@ function createPostgresTables(Database_Abstract $db)
     //TODO: use BIGINT for time() timestamp to avoid the Year-2038 problem
 
     $db->ex(
-"CREATE TABLE {$db->prefix}lists (
+"CREATE TABLE {$db->getPrefix()}lists (
     id INTEGER NOT NULL GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     uuid CHAR(36) NOT NULL default '',
     ow INTEGER NOT NULL default 0,
@@ -440,10 +440,10 @@ function createPostgresTables(Database_Abstract $db)
     taskview INTEGER NOT NULL default 0,
     extra TEXT
 ) ");
-    $db->ex("CREATE UNIQUE INDEX {$db->prefix}lists_uuid ON {$db->prefix}lists (uuid)");
+    $db->ex("CREATE UNIQUE INDEX {$db->getPrefix()}lists_uuid ON {$db->getPrefix()}lists (uuid)");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}todolist (
+"CREATE TABLE {$db->getPrefix()}todolist (
     id INTEGER NOT NULL GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     uuid CHAR(36) NOT NULL default '',
     list_id INTEGER NOT NULL default 0,
@@ -457,41 +457,41 @@ function createPostgresTables(Database_Abstract $db)
     ow INTEGER NOT NULL default 0,
     duedate DATE default NULL
 ) ");
-    $db->ex("CREATE INDEX {$db->prefix}todo_list_id ON {$db->prefix}todolist (list_id)");
-    $db->ex("CREATE UNIQUE INDEX {$db->prefix}todo_uuid ON {$db->prefix}todolist (uuid)");
+    $db->ex("CREATE INDEX {$db->getPrefix()}todo_list_id ON {$db->getPrefix()}todolist (list_id)");
+    $db->ex("CREATE UNIQUE INDEX {$db->getPrefix()}todo_uuid ON {$db->getPrefix()}todolist (uuid)");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}tags (
+"CREATE TABLE {$db->getPrefix()}tags (
     id INTEGER NOT NULL GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     name VARCHAR(250) NOT NULL DEFAULT ''
 ) ");
-    $db->ex("CREATE UNIQUE INDEX {$db->prefix}tags_lower_name ON {$db->prefix}tags ((LOWER(name)))");
+    $db->ex("CREATE UNIQUE INDEX {$db->getPrefix()}tags_lower_name ON {$db->getPrefix()}tags ((LOWER(name)))");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}tag2task (
+"CREATE TABLE {$db->getPrefix()}tag2task (
     tag_id INTEGER NOT NULL,
     task_id INTEGER NOT NULL,
     list_id INTEGER NOT NULL
 ) ");
-    $db->ex("CREATE INDEX {$db->prefix}tag2task_tag_id ON {$db->prefix}tag2task (tag_id)");
-    $db->ex("CREATE INDEX {$db->prefix}tag2task_task_id ON {$db->prefix}tag2task (task_id)");
-    $db->ex("CREATE INDEX {$db->prefix}tag2task_list_id ON {$db->prefix}tag2task (list_id)");
+    $db->ex("CREATE INDEX {$db->getPrefix()}tag2task_tag_id ON {$db->getPrefix()}tag2task (tag_id)");
+    $db->ex("CREATE INDEX {$db->getPrefix()}tag2task_task_id ON {$db->getPrefix()}tag2task (task_id)");
+    $db->ex("CREATE INDEX {$db->getPrefix()}tag2task_list_id ON {$db->getPrefix()}tag2task (list_id)");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}settings (
+"CREATE TABLE {$db->getPrefix()}settings (
     param_key   VARCHAR(250) NOT NULL default '',
     param_value TEXT
 ) ");
-    $db->ex("CREATE UNIQUE INDEX {$db->prefix}settings_key ON {$db->prefix}settings (param_key)");
+    $db->ex("CREATE UNIQUE INDEX {$db->getPrefix()}settings_key ON {$db->getPrefix()}settings (param_key)");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}sessions (
+"CREATE TABLE {$db->getPrefix()}sessions (
     id          VARCHAR(64) NOT NULL default '',
     data        TEXT,
     last_access INTEGER NOT NULL default 0,
     expires     INTEGER NOT NULL default 0
 ) ");
-    $db->ex("CREATE UNIQUE INDEX {$db->prefix}sessions_id ON {$db->prefix}sessions (id)");
+    $db->ex("CREATE UNIQUE INDEX {$db->getPrefix()}sessions_id ON {$db->getPrefix()}sessions (id)");
 }
 
 
@@ -499,7 +499,7 @@ function createPostgresTables(Database_Abstract $db)
 function createSqliteTables(Database_Abstract $db)
 {
     $db->ex(
-"CREATE TABLE {$db->prefix}lists (
+"CREATE TABLE {$db->getPrefix()}lists (
     id INTEGER PRIMARY KEY,
     uuid CHAR(36) NOT NULL,
     ow INTEGER NOT NULL default 0,
@@ -512,10 +512,10 @@ function createSqliteTables(Database_Abstract $db)
     extra TEXT
 ) ");
 
-    $db->ex("CREATE UNIQUE INDEX lists_uuid ON {$db->prefix}lists (uuid)");
+    $db->ex("CREATE UNIQUE INDEX lists_uuid ON {$db->getPrefix()}lists (uuid)");
 
     $db->ex(
-"CREATE TABLE {$db->prefix}todolist (
+"CREATE TABLE {$db->getPrefix()}todolist (
     id INTEGER PRIMARY KEY,
     uuid CHAR(36) NOT NULL default '',
     list_id INTEGER UNSIGNED NOT NULL default 0,
@@ -529,68 +529,68 @@ function createSqliteTables(Database_Abstract $db)
     ow INTEGER NOT NULL default 0,
     duedate DATE default NULL
 ) ");
-    $db->ex("CREATE INDEX todo_list_id ON {$db->prefix}todolist (list_id)");
-    $db->ex("CREATE UNIQUE INDEX todo_uuid ON {$db->prefix}todolist (uuid)");
+    $db->ex("CREATE INDEX todo_list_id ON {$db->getPrefix()}todolist (list_id)");
+    $db->ex("CREATE UNIQUE INDEX todo_uuid ON {$db->getPrefix()}todolist (uuid)");
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}tags (
+"CREATE TABLE {$db->getPrefix()}tags (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
     name VARCHAR(250) NOT NULL DEFAULT '' COLLATE UTF8CI
 ) ");
-    $db->ex("CREATE INDEX tags_name ON {$db->prefix}tags (name)"); //NB: unique in mysql
+    $db->ex("CREATE INDEX tags_name ON {$db->getPrefix()}tags (name)"); //NB: unique in mysql
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}tag2task (
+"CREATE TABLE {$db->getPrefix()}tag2task (
     tag_id INTEGER NOT NULL,
     task_id INTEGER NOT NULL,
     list_id INTEGER NOT NULL
 ) ");
-    $db->ex("CREATE INDEX tag2task_tag_id ON {$db->prefix}tag2task (tag_id)");
-    $db->ex("CREATE INDEX tag2task_task_id ON {$db->prefix}tag2task (task_id)");
-    $db->ex("CREATE INDEX tag2task_list_id ON {$db->prefix}tag2task (list_id)");    /* for tagcloud */
+    $db->ex("CREATE INDEX tag2task_tag_id ON {$db->getPrefix()}tag2task (tag_id)");
+    $db->ex("CREATE INDEX tag2task_task_id ON {$db->getPrefix()}tag2task (task_id)");
+    $db->ex("CREATE INDEX tag2task_list_id ON {$db->getPrefix()}tag2task (list_id)");    /* for tagcloud */
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}settings (
+"CREATE TABLE {$db->getPrefix()}settings (
     param_key   VARCHAR(250) NOT NULL default '',
     param_value TEXT
 ) ");
 
-    $db->ex("CREATE UNIQUE INDEX settings_key ON {$db->prefix}settings (param_key COLLATE NOCASE)");
+    $db->ex("CREATE UNIQUE INDEX settings_key ON {$db->getPrefix()}settings (param_key COLLATE NOCASE)");
 
 
     $db->ex(
-"CREATE TABLE {$db->prefix}sessions (
+"CREATE TABLE {$db->getPrefix()}sessions (
     id          VARCHAR(64) NOT NULL default '',
     data        TEXT,
     last_access INTEGER UNSIGNED NOT NULL default 0,
     expires     INTEGER UNSIGNED NOT NULL default 0
 ) ");
 
-    $db->ex("CREATE UNIQUE INDEX sessions_id ON {$db->prefix}sessions (id COLLATE NOCASE)");
+    $db->ex("CREATE UNIQUE INDEX sessions_id ON {$db->getPrefix()}sessions (id COLLATE NOCASE)");
 }
 
 
 function databaseVersion(Database_Abstract $db): string
 {
     if ( !$db ) return '';
-    if ( !$db->tableExists($db->prefix.'todolist') ) return '';
+    if ( !$db->tableExists($db->getTableWithPrefix('todolist')) ) return '';
     $v = '1.0';
-    if ( !$db->tableExists($db->prefix.'tags') ) return $v;
+    if ( !$db->tableExists($db->getTableWithPrefix('tags')) ) return $v;
     $v = '1.1';
-    if ( !$db->tableFieldExists($db->prefix.'todolist', 'duedate') ) return $v;
+    if ( !$db->tableFieldExists($db->getTableWithPrefix('todolist'), 'duedate') ) return $v;
     $v = '1.2';
-    if ( !$db->tableExists($db->prefix.'lists') ) return $v;
+    if ( !$db->tableExists($db->getTableWithPrefix('lists')) ) return $v;
     $v = '1.3.0';
-    if ( !$db->tableFieldExists($db->prefix.'todolist', 'd_completed') ) return $v;
+    if ( !$db->tableFieldExists($db->getTableWithPrefix('todolist'), 'd_completed') ) return $v;
     $v = '1.3.1';
-    if ( !$db->tableFieldExists($db->prefix.'todolist', 'd_edited') ) return $v;
+    if ( !$db->tableFieldExists($db->getTableWithPrefix('todolist'), 'd_edited') ) return $v;
     $v = '1.4';
-    if ( !$db->tableExists($db->prefix.'settings') ) return $v;
+    if ( !$db->tableExists($db->getTableWithPrefix('settings')) ) return $v;
     $v = '1.7';
-    if ( $db->tableFieldExists($db->prefix.'todolist', 'tags') ) return $v;
+    if ( $db->tableFieldExists($db->getTableWithPrefix('todolist'), 'tags') ) return $v;
     $v = '1.8';
     return $v;
 }
@@ -790,25 +790,25 @@ function update_14_17(Database_Abstract $db, $dbtype)
 
     if($dbtype=='mysql')
     {
-        $db->ex("ALTER TABLE {$db->prefix}lists ADD `extra` TEXT");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists ADD `extra` TEXT");
 
         # increase the length of list and tag name
         # (not applicable to sqlite because it uses VARCHAR fields of any length as TEXT)
-        $db->ex("ALTER TABLE {$db->prefix}todolist CHANGE `tags` `tags` VARCHAR(2000) NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}tags CHANGE `name` `name` VARCHAR(250) NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}lists CHANGE `name` `name` VARCHAR(250) NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist CHANGE `tags` `tags` VARCHAR(2000) NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}tags CHANGE `name` `name` VARCHAR(250) NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists CHANGE `name` `name` VARCHAR(250) NOT NULL default '' ");
 
         # convert charset to utf8mb4
 
-        $db->ex("ALTER TABLE {$db->prefix}lists    CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
-        $db->ex("ALTER TABLE {$db->prefix}todolist CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
-        $db->ex("ALTER TABLE {$db->prefix}tags     CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
-        $db->ex("ALTER TABLE {$db->prefix}tag2task CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists    CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        $db->ex("ALTER TABLE {$db->getPrefix()}tags     CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
+        $db->ex("ALTER TABLE {$db->getPrefix()}tag2task CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci");
 
         # create settings table
 
         $db->ex(
-"CREATE TABLE {$db->prefix}settings (
+"CREATE TABLE {$db->getPrefix()}settings (
  `param_key`   VARCHAR(250) NOT NULL default '',
  `param_value` TEXT,
 UNIQUE KEY `param_key` (`param_key`)
@@ -817,7 +817,7 @@ UNIQUE KEY `param_key` (`param_key`)
         # create sessions table
 
         $db->ex(
-"CREATE TABLE {$db->prefix}sessions (
+"CREATE TABLE {$db->getPrefix()}sessions (
  `id`          VARCHAR(64) NOT NULL default '',
  `data`        TEXT,
  `last_access` INT UNSIGNED NOT NULL default 0,
@@ -829,28 +829,28 @@ UNIQUE KEY `id` (`id`)
 
     else #sqlite
     {
-        $db->ex("ALTER TABLE {$db->prefix}lists ADD extra TEXT");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists ADD extra TEXT");
 
         # settings
 
         $db->ex(
-"CREATE TABLE {$db->prefix}settings (
+"CREATE TABLE {$db->getPrefix()}settings (
  param_key   VARCHAR(100) NOT NULL default '',
  param_value TEXT
 ) ");
-        $db->ex("CREATE UNIQUE INDEX settings_key ON {$db->prefix}settings (param_key COLLATE NOCASE)");
+        $db->ex("CREATE UNIQUE INDEX settings_key ON {$db->getPrefix()}settings (param_key COLLATE NOCASE)");
 
         # sessions
 
         $db->ex(
-"CREATE TABLE {$db->prefix}sessions (
+"CREATE TABLE {$db->getPrefix()}sessions (
  id          VARCHAR(250) NOT NULL default '',
  data        TEXT,
  last_access INTEGER UNSIGNED NOT NULL default 0,
  expires     INTEGER UNSIGNED NOT NULL default 0
 ) ");
 
-        $db->ex("CREATE UNIQUE INDEX sessions_id ON {$db->prefix}sessions (id COLLATE NOCASE)");
+        $db->ex("CREATE UNIQUE INDEX sessions_id ON {$db->getPrefix()}sessions (id COLLATE NOCASE)");
     }
 
     $db->ex("COMMIT");
@@ -870,9 +870,9 @@ function update_17_18(Database_Abstract $db, $dbtype)
         // Use UTF8CI collate. Old sqlite does not support DROP COLUMN (before v3.35.0 2021-03-12)
         $db->ex("DROP INDEX todo_list_id");
         $db->ex("DROP INDEX todo_uuid");
-        $db->ex("ALTER TABLE {$db->prefix}todolist RENAME TO {$db->prefix}todolist_old");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist RENAME TO {$db->getPrefix()}todolist_old");
         $db->ex(
-            "CREATE TABLE {$db->prefix}todolist (
+            "CREATE TABLE {$db->getPrefix()}todolist (
                 id INTEGER PRIMARY KEY,
                 uuid CHAR(36) NOT NULL default '',
                 list_id INTEGER UNSIGNED NOT NULL default 0,
@@ -886,45 +886,45 @@ function update_17_18(Database_Abstract $db, $dbtype)
                 ow INTEGER NOT NULL default 0,
                 duedate DATE default NULL )"
         );
-        $db->ex("INSERT INTO {$db->prefix}todolist SELECT id,uuid,list_id,d_created,d_completed,d_edited,compl,title,note,prio,ow,duedate FROM {$db->prefix}todolist_old");
-        $db->ex("CREATE INDEX todo_list_id ON {$db->prefix}todolist (list_id)");
-        $db->ex("CREATE UNIQUE INDEX todo_uuid ON {$db->prefix}todolist (uuid)");
-        $db->ex("DROP TABLE {$db->prefix}todolist_old");
+        $db->ex("INSERT INTO {$db->getPrefix()}todolist SELECT id,uuid,list_id,d_created,d_completed,d_edited,compl,title,note,prio,ow,duedate FROM {$db->getPrefix()}todolist_old");
+        $db->ex("CREATE INDEX todo_list_id ON {$db->getPrefix()}todolist (list_id)");
+        $db->ex("CREATE UNIQUE INDEX todo_uuid ON {$db->getPrefix()}todolist (uuid)");
+        $db->ex("DROP TABLE {$db->getPrefix()}todolist_old");
 
         $db->ex("DROP INDEX tags_name");
-        $db->ex("ALTER TABLE {$db->prefix}tags RENAME TO {$db->prefix}tags_old");
+        $db->ex("ALTER TABLE {$db->getPrefix()}tags RENAME TO {$db->getPrefix()}tags_old");
         $db->ex(
-            "CREATE TABLE {$db->prefix}tags (
+            "CREATE TABLE {$db->getPrefix()}tags (
                 id INTEGER PRIMARY KEY AUTOINCREMENT,
                 name VARCHAR(250) NOT NULL DEFAULT '' COLLATE UTF8CI )"
         );
-        $db->ex("INSERT INTO {$db->prefix}tags SELECT * FROM {$db->prefix}tags_old");
-        $db->ex("CREATE INDEX tags_name ON {$db->prefix}tags (name)");
-        $db->ex("DROP TABLE {$db->prefix}tags_old");
+        $db->ex("INSERT INTO {$db->getPrefix()}tags SELECT * FROM {$db->getPrefix()}tags_old");
+        $db->ex("CREATE INDEX tags_name ON {$db->getPrefix()}tags (name)");
+        $db->ex("DROP TABLE {$db->getPrefix()}tags_old");
     }
     else // mysql
     {
-        $db->ex("ALTER TABLE {$db->prefix}todolist DROP COLUMN tags");
-        $db->ex("ALTER TABLE {$db->prefix}todolist DROP COLUMN tags_ids");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist DROP COLUMN tags");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist DROP COLUMN tags_ids");
 
         // if mysql db was created in v1.7.x then
         // tags.name field has length of 50 instead of 250,
         // settings.param_key field has length of 100 instead of 250
-        $db->ex("ALTER TABLE {$db->prefix}lists MODIFY `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}lists MODIFY `name` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}lists MODIFY `extra` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists MODIFY `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists MODIFY `name` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}lists MODIFY `extra` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
 
-        $db->ex("ALTER TABLE {$db->prefix}todolist MODIFY `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}todolist MODIFY `title` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}todolist MODIFY `note` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist MODIFY `uuid` CHAR(36) CHARACTER SET latin1 NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist MODIFY `title` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}todolist MODIFY `note` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
 
-        $db->ex("ALTER TABLE {$db->prefix}tags MODIFY `name` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}tags MODIFY `name` VARCHAR(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci NOT NULL default '' ");
 
-        $db->ex("ALTER TABLE {$db->prefix}settings MODIFY `param_key` VARCHAR(250) CHARACTER SET latin1 NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}settings MODIFY `param_value` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}settings MODIFY `param_key` VARCHAR(250) CHARACTER SET latin1 NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}settings MODIFY `param_value` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
 
-        $db->ex("ALTER TABLE {$db->prefix}sessions MODIFY `id` VARCHAR(64) CHARACTER SET latin1 NOT NULL default '' ");
-        $db->ex("ALTER TABLE {$db->prefix}sessions MODIFY `data` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}sessions MODIFY `id` VARCHAR(64) CHARACTER SET latin1 NOT NULL default '' ");
+        $db->ex("ALTER TABLE {$db->getPrefix()}sessions MODIFY `data` TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci ");
     }
 
     $db->ex("COMMIT");