diff --git a/src/includes/class.db.mysql.php b/src/includes/class.db.mysql.php
index 63731e7..20385df 100644
--- a/src/includes/class.db.mysql.php
+++ b/src/includes/class.db.mysql.php
@@ -147,7 +147,7 @@ class Database_Mysql extends Database_Abstract
             }
             $query .= $m[$i];
         }
-        $this->lastQuery = $query;
+        $this->setLastQuery($query);
         $dbr = new DatabaseResult_Mysql($this->dbh, $query, $resultless);
         $this->affected = $dbr->rowsAffected();
         return $dbr;
diff --git a/src/includes/class.db.mysqli.php b/src/includes/class.db.mysqli.php
index 679e9bc..4f6e0f2 100644
--- a/src/includes/class.db.mysqli.php
+++ b/src/includes/class.db.mysqli.php
@@ -122,7 +122,7 @@ class Database_Mysqli extends Database_Abstract
             }
             $query .= $m[$i];
         }
-        $this->lastQuery = $query;
+        $this->setLastQuery($query);
         return new DatabaseResult_Mysqli($this->dbh, $query, $resultless);
     }
 
diff --git a/src/includes/class.db.postgres.php b/src/includes/class.db.postgres.php
index dfc22ae..ea251f2 100644
--- a/src/includes/class.db.postgres.php
+++ b/src/includes/class.db.postgres.php
@@ -150,7 +150,7 @@ class Database_Postgres extends Database_Abstract
             }
             $query .= $m[$i];
         }
-        $this->lastQuery = $query;
+        $this->setLastQuery($query);
         $dbr = new DatabaseResult_Postgres($this->dbh, $query, $resultless);
         $this->affected = $dbr->rowsAffected();
         return $dbr;
diff --git a/src/includes/class.db.sqlite3.php b/src/includes/class.db.sqlite3.php
index 6a86cde..9f38d8b 100644
--- a/src/includes/class.db.sqlite3.php
+++ b/src/includes/class.db.sqlite3.php
@@ -151,7 +151,7 @@ class Database_Sqlite3 extends Database_Abstract
             }
             $query .= $m[$i];
         }
-        $this->lastQuery = $query;
+        $this->setLastQuery($query);
         $dbr = new DatabaseResult_Sqlite3($this->dbh, $query, $resultless);
         $this->affected = $dbr->rowsAffected();
         return $dbr;
diff --git a/src/includes/class.dbconnection.php b/src/includes/class.dbconnection.php
index aa8e44a..8f33262 100644
--- a/src/includes/class.dbconnection.php
+++ b/src/includes/class.dbconnection.php
@@ -46,6 +46,9 @@ abstract class Database_Abstract
     /** @var string */
     protected $lastQuery = '';
 
+    /** @var null|string  */
+    protected $logQueryToFile = null;
+
     abstract function connect(array $params): void;
     abstract function sq(string $query, ?array $values = null);
     abstract function sqa(string $query, ?array $values = null): ?array;
@@ -73,6 +76,22 @@ abstract class Database_Abstract
         }
         $this->prefix = $prefix;
     }
+
+    function setLogQueryToFile(?string $path) {
+        //any checks?
+        $this->logQueryToFile = $path;
+    }
+
+    function setLastQuery(string $lastQuery) {
+        $this->lastQuery = $lastQuery;
+        if (MTT_DEBUG && $this->logQueryToFile !== null) {
+            $f = fopen($this->logQueryToFile, "a");
+            if ($f) {
+                fwrite($f, $this->lastQuery . "\n");
+                fclose($f);
+            }
+        }
+    }
 }
 
 abstract class DatabaseResult_Abstract