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Using SQLCipher with Android sqlite database file from android

I have a reset database file in a file assets.

How can I use SQLCipherto encrypt a database in android?

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It will be a bit complicated. Since the database file format is different from SQLite and SQLCipher for Android, and since you want to send an unencrypted database, you have to do a few things.

First, I get SQLiteAssetHelperto deliver an unencrypted database to your environment.

Then use the standard SQLCipher for Android to create an empty but encrypted database.

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SQLiteAssetHelper, -...

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, SQLCipher -

, , SQLiteDatabase SQLiteDatabase Android.:

 import info.guardianproject.database.sqlcipher.SQLiteDatabase;
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The following code snippet can be used to create multiple tables in an SQLite Cipher database:

Use this import data:

import java.sql.SQLException;
import net.sqlcipher.database.SQLiteDatabase;
import net.sqlcipher.database.SQLiteOpenHelper;
import android.content.ContentValues;  
import android.content.Context;  
import android.database.Cursor;  
import android.util.Log;

/** Helper to the database, manages versions and creation */

    public class DBAdapter extends SQLiteOpenHelper {
        private static final String DATABASE_NAME = "Test";
        private static final int DATABASE_VERSION = 1;

        // Table name
        public static final String TABLE_1 = "Table1";
        public static final String TABLE_2 = "Table2";

        // Column names for Table1 table
        static final String KEY_PASSWORD = "password";
        static final String KEY_USER = "user";

        // Column names for Table2 table
        static final String KEY_EVENT = "event";
        static final String KEY_USERNAME = "username";


        public DBAdapter(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            String sql1 = "create table " + Table_1 + " (" + KEY_USER + " text primary key, " + KEY_PASSWORD + " text not null);";
            String sql2 = "create table " + Table_2 + " (" + KEY_EVENT + " text primary key, " + KEY_USERNAME + " text not null FOREIGN KEY(" + KEY_USERNAME + ") REFERENCES " + TABLE_1 + "(" + KEY_USER + "));";
            db.execSQL(sql1);
            db.execSQL(sql2);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            if (oldVersion >= newVersion){
                return;
            }

            String sql = null;
            if (oldVersion == 1) 
                sql = "alter table " + TABLE_1 + " add note text;";
            if (oldVersion == 2)
                sql = "";

            Log.d("EventsData", "onUpgrade  : " + sql);
            if (sql != null)
                db.execSQL(sql);
        } 

        public Cursor getAllUsers(String username, SQLiteDatabase db){
            return db.query(TABLE_1, ...);
        }

        public Cursor getAllEvents(String event, SQLiteDatabase db){
            return db.query(TABLE_2, ...);
        }
   }

Now you can use all CRUD methods for both tables. Just make sure that each method has SQLiteDatabasean argument as shown in the method getAllUsers().

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