diff --git a/app/src/main/java/io/legado/app/data/AppDatabase.kt b/app/src/main/java/io/legado/app/data/AppDatabase.kt
index 555f827d2..04dda1df6 100644
--- a/app/src/main/java/io/legado/app/data/AppDatabase.kt
+++ b/app/src/main/java/io/legado/app/data/AppDatabase.kt
@@ -1,18 +1,11 @@
 package io.legado.app.data
 
 import android.content.Context
-import android.database.Cursor
 import androidx.room.Database
 import androidx.room.Room
 import androidx.room.RoomDatabase
-import androidx.sqlite.db.SupportSQLiteDatabase
-import com.google.gson.JsonArray
-import com.google.gson.JsonObject
 import io.legado.app.data.dao.*
 import io.legado.app.data.entities.*
-import io.legado.app.help.FileHelp
-import io.legado.app.utils.GSON
-import java.io.File
 
 
 @Database(
@@ -29,50 +22,8 @@ abstract class AppDatabase : RoomDatabase() {
         fun createDatabase(context: Context): AppDatabase {
             return Room.databaseBuilder(context, AppDatabase::class.java, DATABASE_NAME)
                 .fallbackToDestructiveMigration()
-                .addCallback(callback)
                 .build()
         }
-
-        val callback = object : Callback() {
-            override fun onOpen(db: SupportSQLiteDatabase) {
-
-            }
-
-            override fun onDestructiveMigration(db: SupportSQLiteDatabase) {
-
-            }
-        }
-
-        private fun backup(database: SupportSQLiteDatabase) {
-            val forms = arrayOf(
-                "books", "book_groups", "bookmarks", "book_sources", "cookies",
-                "replace_rules", "rssSources", "search_keywords", "rssArticles"
-            )
-            forms.forEach { form ->
-                database.query("select * from $form").let {
-                    val ja = JsonArray()
-                    while (it.moveToNext()) {
-                        val jo = JsonObject()
-                        for (i in 0 until it.columnCount) {
-                            if (!it.isNull(i)) {
-                                when (it.getType(i)) {
-                                    Cursor.FIELD_TYPE_FLOAT ->
-                                        jo.addProperty(it.getColumnName(i), it.getFloat(i))
-                                    Cursor.FIELD_TYPE_INTEGER ->
-                                        jo.addProperty(it.getColumnName(i), it.getInt(i))
-                                    else -> jo.addProperty(it.getColumnName(i), it.getString(i))
-                                }
-                            }
-                        }
-                        ja.add(jo)
-                    }
-                    it.close()
-                    FileHelp.getFile(FileHelp.getCachePath() + File.separator + "db" + File.separator + form + ".json")
-                        .writeText(GSON.toJson(ja))
-                }
-                database.execSQL("drop table $form")
-            }
-        }
     }
 
     abstract fun bookDao(): BookDao