diff --git a/td/telegram/Td.cpp b/td/telegram/Td.cpp
index af9a37345..e9ddb3091 100644
--- a/td/telegram/Td.cpp
+++ b/td/telegram/Td.cpp
@@ -2567,17 +2567,6 @@ vector<td_api::object_ptr<td_api::Update>> Td::get_fake_current_state() const {
   return updates;
 }
 
-DbKey Td::as_db_key(string key) {
-  // Database will still be effectively not encrypted, but
-  // 1. SQLite database will be protected from corruption, because that's how sqlcipher works
-  // 2. security through obscurity
-  // 3. no need for reencryption of SQLite database
-  if (key.empty()) {
-    return DbKey::raw_key("cucumber");
-  }
-  return DbKey::raw_key(std::move(key));
-}
-
 void Td::request(uint64 id, tl_object_ptr<td_api::Function> function) {
   if (id == 0) {
     LOG(ERROR) << "Ignore request with ID == 0: " << to_string(function);
@@ -3802,7 +3791,7 @@ Result<std::pair<Td::Parameters, TdDb::Parameters>> Td::get_parameters(
   result.first.api_hash_ = std::move(parameters->api_hash_);
   result.first.use_secret_chats_ = parameters->use_secret_chats_;
 
-  result.second.encryption_key_ = as_db_key(std::move(parameters->database_encryption_key_));
+  result.second.encryption_key_ = TdDb::as_db_key(std::move(parameters->database_encryption_key_));
   result.second.database_directory_ = std::move(parameters->database_directory_);
   result.second.files_directory_ = std::move(parameters->files_directory_);
   result.second.is_test_dc_ = parameters->use_test_dc_;
@@ -3850,7 +3839,7 @@ void Td::on_request(uint64 id, const td_api::setTdlibParameters &request) {
 
 void Td::on_request(uint64 id, td_api::setDatabaseEncryptionKey &request) {
   CREATE_OK_REQUEST_PROMISE();
-  G()->td_db()->get_binlog()->change_key(as_db_key(std::move(request.new_encryption_key_)), std::move(promise));
+  G()->td_db()->get_binlog()->change_key(TdDb::as_db_key(std::move(request.new_encryption_key_)), std::move(promise));
 }
 
 void Td::on_request(uint64 id, const td_api::getAuthorizationState &request) {
diff --git a/td/telegram/Td.h b/td/telegram/Td.h
index ee030565a..16dda7e13 100644
--- a/td/telegram/Td.h
+++ b/td/telegram/Td.h
@@ -17,8 +17,6 @@
 #include "td/telegram/telegram_api.h"
 #include "td/telegram/TermsOfService.h"
 
-#include "td/db/DbKey.h"
-
 #include "td/actor/actor.h"
 #include "td/actor/MultiTimeout.h"
 
@@ -2020,8 +2018,6 @@ class Td final : public Actor {
   void on_request(uint64 id, td_api::testCallVectorString &request);
   void on_request(uint64 id, td_api::testCallVectorStringObject &request);
 
-  static DbKey as_db_key(string key);
-
   struct Parameters {
     int32 api_id_ = 0;
     string api_hash_;
diff --git a/td/telegram/TdDb.cpp b/td/telegram/TdDb.cpp
index 3cf446caa..5998610c4 100644
--- a/td/telegram/TdDb.cpp
+++ b/td/telegram/TdDb.cpp
@@ -662,6 +662,13 @@ Status TdDb::check_parameters(Parameters &parameters) {
   return Status::OK();
 }
 
+DbKey TdDb::as_db_key(string key) {
+  if (key.empty()) {
+    return DbKey::raw_key("cucumber");
+  }
+  return DbKey::raw_key(std::move(key));
+}
+
 void TdDb::change_key(DbKey key, Promise<> promise) {
   get_binlog()->change_key(std::move(key), std::move(promise));
 }
diff --git a/td/telegram/TdDb.h b/td/telegram/TdDb.h
index 7e43a698e..708139232 100644
--- a/td/telegram/TdDb.h
+++ b/td/telegram/TdDb.h
@@ -148,6 +148,8 @@ class TdDb {
   StoryDbSyncInterface *get_story_db_sync();
   StoryDbAsyncInterface *get_story_db_async();
 
+  static DbKey as_db_key(string key);
+
   void change_key(DbKey key, Promise<> promise);
 
   void with_db_path(const std::function<void(CSlice)> &callback);