diff --git a/README.en.md b/README.en.md
index b1f0bf8..55a216e 100644
--- a/README.en.md
+++ b/README.en.md
@@ -16,7 +16,7 @@ UPDATE `judge_state` JOIN `problem` ON `problem`.`id` = `judge_state`.`problem_i
 ALTER TABLE `syzoj`.`judge_state` ADD INDEX `judge_state_is_public` (`id`, `is_public`, `type_info`, `type`);
 ```
 
-Who upgrade from a commit BEFORE [26d66ceef24fbb35481317453bcb89ead6c69076](https://github.com/syzoj/syzoj/commit/26d66ceef24fbb35481317453bcb89ead6c69076) (Nov 5, 2018) and not using SQLite **MUST** perform the following SQL on the database.
+Who upgrade from a commit BEFORE [26d66ceef24fbb35481317453bcb89ead6c69076](https://github.com/syzoj/syzoj/commit/26d66ceef24fbb35481317453bcb89ead6c69076) (Nov 5, 2018) **MUST** perform the following SQL on the database.
 
 ```sql
 ALTER TABLE contest_player CHANGE score_details score_details JSON NOT NULL;
@@ -27,7 +27,7 @@ ALTER TABLE judge_state CHANGE compilation compilation JSON NOT NULL;
 ALTER TABLE judge_state CHANGE result result JSON NOT NULL;
 ```
 
-Who upgraded from a commit BEFORE [84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23](https://github.com/syzoj/syzoj/commit/84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23) (Nov 6, 2018) **MUST** perform the following SQL on the database. **Notice**: This SQL haven't been tested on a non-MySQL database.
+Who upgraded from a commit BEFORE [84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23](https://github.com/syzoj/syzoj/commit/84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23) (Nov 6, 2018) **MUST** perform the following SQL on the database.
 
 ```sql
 ALTER TABLE `problem` ADD `publicize_time` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP AFTER `type`;
diff --git a/README.md b/README.md
index 17dce38..647353a 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ UPDATE `judge_state` JOIN `problem` ON `problem`.`id` = `judge_state`.`problem_i
 ALTER TABLE `syzoj`.`judge_state` ADD INDEX `judge_state_is_public` (`id`, `is_public`, `type_info`, `type`);
 ```
 
-从该 commit [26d66ceef24fbb35481317453bcb89ead6c69076](https://github.com/syzoj/syzoj/commit/26d66ceef24fbb35481317453bcb89ead6c69076)（2018 年 11 月 5 日）前更新且使用除 SQLite 外数据库软件的用户**必须**在其数据库上执行以下 SQL 语句。
+从该 commit [26d66ceef24fbb35481317453bcb89ead6c69076](https://github.com/syzoj/syzoj/commit/26d66ceef24fbb35481317453bcb89ead6c69076)（2018 年 11 月 5 日）前更新的用户**必须**在其数据库上执行以下 SQL 语句。
 
 ```sql
 ALTER TABLE contest_player CHANGE score_details score_details JSON NOT NULL;
@@ -27,7 +27,7 @@ ALTER TABLE judge_state CHANGE compilation compilation JSON NOT NULL;
 ALTER TABLE judge_state CHANGE result result JSON NOT NULL;
 ```
 
-从该 commit [84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23](https://github.com/syzoj/syzoj/commit/84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23)（2018 年 11 月 6 日）前更新的用户**必须**在其数据库上执行以下 SQL 语句。**注意**：此语句尚未在除 MySQL 外的数据库系统中测试。
+从该 commit [84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23](https://github.com/syzoj/syzoj/commit/84b9e2d7b51e4ed3ab426621b66cf5ae9e1e1c23)（2018 年 11 月 6 日）前更新的用户**必须**在其数据库上执行以下 SQL 语句。
 
 ```sql
 ALTER TABLE `problem` ADD `publicize_time` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP AFTER `type`;
diff --git a/app.js b/app.js
index 6a57197..28778e1 100644
--- a/app.js
+++ b/app.js
@@ -128,8 +128,7 @@ global.syzoj = {
 
     this.db = new Sequelize(this.config.db.database, this.config.db.username, this.config.db.password, {
       host: this.config.db.host,
-      dialect: this.config.db.dialect,
-      storage: this.config.db.storage ? this.utils.resolvePath(this.config.db.storage) : null,
+      dialect: 'mysql',
       logging: syzoj.production ? false : syzoj.log,
       timezone: require('moment')().format('Z'),
       operatorsAliases: operatorsAliases
diff --git a/config-example.json b/config-example.json
index 276cfa7..5b3d980 100644
--- a/config-example.json
+++ b/config-example.json
@@ -3,12 +3,10 @@
   "hostname": "127.0.0.1",
   "port": "5283",
   "db": {
-    "database": null,
-    "username": null,
+    "database": "syzoj",
+    "username": "syzoj",
     "password": null,
-    "host": null,
-    "dialect": "sqlite",
-    "storage": "syzoj.db"
+    "host": "127.0.0.1"
   },
   "register_mail": false,
   "email": {
diff --git a/package.json b/package.json
index cedbfb8..2c870f6 100644
--- a/package.json
+++ b/package.json
@@ -60,7 +60,6 @@
     "sequelize": "^4.41.0",
     "session-file-store": "^1.0.0",
     "socket.io": "^2.0.3",
-    "sqlite3": "^4.0.3",
     "syzoj-divine": "^1.0.2",
     "tmp-promise": "^1.0.3",
     "waliyun": "^3.1.1",