diff --git a/app/src/main/java/rikka/searchbyimage/database/DatabaseHelper.java b/app/src/main/java/rikka/searchbyimage/database/DatabaseHelper.java
new file mode 100644
index 0000000..b326be6
--- /dev/null
+++ b/app/src/main/java/rikka/searchbyimage/database/DatabaseHelper.java
@@ -0,0 +1,40 @@
+package rikka.searchbyimage.database;
+
+import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+
+import rikka.searchbyimage.database.table.CustomEngineTable;
+
+/**
+ * Created by Rikka on 2016/1/24.
+ */
+public class DatabaseHelper extends SQLiteOpenHelper{
+    public static final int DATABASE_VERSION = 2;
+    public static final String DATABASE_NAME = "search_engines.db";
+
+    private static DatabaseHelper instance;
+
+    public DatabaseHelper(Context context) {
+        super(context, DATABASE_NAME, null, DATABASE_VERSION);
+    }
+
+    public static synchronized DatabaseHelper instance(Context context) {
+        if (instance == null) {
+            instance = new DatabaseHelper(context);
+        }
+        return instance;
+    }
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        db.execSQL(CustomEngineTable.SQL_CREATE_ENTRIES);
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        if (newVersion == 2) {
+            db.execSQL("ALTER TABLE " + CustomEngineTable.TABLE_NAME + " ADD " + CustomEngineTable.COLUMN_ENABLED + " integer NOT NULL DEFAULT(1)");
+        }
+    }
+}
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