androiddatabasesqlitesqlitemanager

Sqlite manager couldn't open my android database


When I try to open my database file with sqlite database it shows me the following errors:

[2014-05-19 23:50:51] Failed to open database file db_penpal.db
[2014-05-19 23:50:51] null

Does that mean that my database contains some bugs? If yes, how can I solve that?

Thanks in advance.

public class Database_handler extends SQLiteOpenHelper {

    private static final int database_version = 1;
    public static final String database_name = "db_e_pal.db";

    public Database_handler(Context context) {
        super(context, database_name, null, database_version);

    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        //Creation de la table user
        String create_t_user
                = "CREATE TABLE IF NOT EXISTS user ("
                + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                + "username varchar(20) NOT NULL,"
                + "password varchar(20) NOT NULL,"
                + "connected INTEGER(0) NOT NULL);";
        String create_t_friend_request
                = "CREATE TABLE IF NOT EXISTS friend_request ("
                + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                + "username varchar(20) NOT NULL,"
                + "ID_last_message INTEGER NOT NULL);";

        String create_t_friend
                = "CREATE TABLE IF NOT EXISTS friend ("
                + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                + "username varchar(20) NOT NULL," 
                + "connected INTEGER(0) NOT NULL);";

        String create_t_message
                = "CREATE TABLE IF NOT EXISTS message ("
                + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                + "ID_friend INTEGER NOT NULL,"
                + "Sent bit(1) NOT NULL,"
                + "Body text NOT NULL,"
                + "DATE datetime NOT NULL);";
        //execution des requetes
        db.execSQL(create_t_user);
        db.execSQL(create_t_friend_request);
        db.execSQL(create_t_friend);
        db.execSQL(create_t_message);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Supprimer les anciennes tables si elles existent
        // Requetes pou les suppressions
        String drop_t_user = "DROP TABLE IF EXISTS user";
        String drop_t_message = "DROP TABLE IF EXISTS message";
        String drop_t_friend = "DROP TABLE IF EXISTS friend";
        String drop_t_friend_request = "DROP TABLE IF EXISTS friend_request";
        // Suppression des tables
        db.execSQL(drop_t_user);
        db.execSQL(drop_t_message);
        db.execSQL(drop_t_friend);

        db.execSQL(drop_t_friend_request);
        // Create tables again
        onCreate(db);
    }

    //Les operation faites sur la bd "les CRUD"
    //Vider la base de donnée 
    public void empty() {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete("user", null, null);
        db.delete("message", null, null);
        db.delete("friend", null, null);
        db.delete("friend_request", null, null);
        db.close();
    }
}

This is the log:

05-20 04:35:10.757: D/dalvikvm(3907): GC_EXTERNAL_ALLOC freed 458K, 55% free 3317K/7303K, 
external 1070K/1570K, paused 72ms
05-20 04:35:37.117: D/dalvikvm(3907): GC_CONCURRENT freed 435K, 47% free 3887K/7303K, 
external 1530K/2027K, paused 4ms+5ms
05-20 04:35:37.117: D/Cursor(3907): Database path: db_e_pal.db
05-20 04:35:37.117: D/Cursor(3907): Table name   : null
05-20 04:35:37.117: D/Cursor(3907): Database path: db_e_pal.db
05-20 04:35:37.117: D/Cursor(3907): Table name   : null

Solution

  • public class DbHelper extends SQLiteOpenHelper {
    
        // The Android's default system path of your application database.
        private static String PACKAGENAME = "com.xyz";
        private static String DB_PATH = "/data/data/" + PACKAGENAME + "/databases/";
        public static String DB_NAME = "abc.db";
        public static int DELETED = 1;
        public static int UPDATED = 2;
        public static int NEW_RECORD = 3;
    
        private static final String TAG = "DbHelper";
        private SQLiteDatabase myDataBase;
    
        private final Context myContext;
    
        /**
         * Constructor Takes and keeps a reference of the passed context in order to
         * access to the application assets and resources.
         * 
         * @param context
         */
        public DbHelper(final Context context) {
            super(context, DB_NAME, null, 1);
            this.myContext = context;
    
        }
    
        /**
         * Creates a empty database on the system and rewrites it with your own
         * database.
         * */
        public final void createDataBase() throws IOException {
    
            final boolean dbExist = checkDataBase();
            SQLiteDatabase db_Read = null;
            if (dbExist) {
                 String create_t_user
                    = "CREATE TABLE IF NOT EXISTS user ("
                    + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                    + "username varchar(20) NOT NULL,"
                    + "password varchar(20) NOT NULL,"
                    + "connected INTEGER(0) NOT NULL);";
            String create_t_friend_request
                    = "CREATE TABLE IF NOT EXISTS friend_request ("
                    + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                    + "username varchar(20) NOT NULL,"
                    + "ID_last_message INTEGER NOT NULL);";
    
            String create_t_friend
                    = "CREATE TABLE IF NOT EXISTS friend ("
                    + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                    + "username varchar(20) NOT NULL," 
                    + "connected INTEGER(0) NOT NULL);";
    
            String create_t_message
                    = "CREATE TABLE IF NOT EXISTS message ("
                    + "ID INTEGER PRIMARY KEY AUTOINCREMENT,"
                    + "ID_friend INTEGER NOT NULL,"
                    + "Sent bit(1) NOT NULL,"
                    + "Body text NOT NULL,"
                    + "DATE datetime NOT NULL);";
            //execution des requetes
            db_Read .execSQL(create_t_user);
            db_Read .execSQL(create_t_friend_request);
            db_Read .execSQL(create_t_friend);
            db_Read .execSQL(create_t_message);
            } else {
                // By calling this method and empty database will be created into
                // the default system path
                // of your application so we are gonna be able to overwrite that
                // database with our database.
                // By calling this method and empty database will be created into
                // the default system path
                // of your application so we are gonna be able to overwrite that
                // database with our database.
                // db_Read = this.getReadableDatabase(DB_Internal);
                db_Read = this.getReadableDatabase();
                db_Read.close();
    
                copyDataBase();
    
            }
        }
    
        /**
         * Restore whole database without any data
         * 
         * @throws IOException
         */
        public final void RestoreDatabase() throws IOException {
            SQLiteDatabase db_Read = this.getReadableDatabase();
            db_Read.close();
    
            copyDataBase();
            Log.i(TAG, "Database REstored");
        }
    
        /**
         * Check if the database already exist to avoid re-copying the file each
         * time you open the application.
         * 
         * @return true if it exists, false if it doesn't
         */
        private boolean checkDataBase() {
            final File dbFile = new File(DB_PATH + DB_NAME);
            return dbFile.exists();
        }
    
        /**
         * Copies your database from your local assets-folder to the just created
         * empty database in the system folder, from where it can be accessed and
         * handled. This is done by transfering bytestream.
         * 
         * @throws IOException
         * */
        private void copyDataBase() throws IOException {
    
            // Open your local db as the input stream
            final InputStream myInput = myContext.getAssets().open(DB_NAME);
    
            // Path to the just created empty db
            final String outFileName = DB_PATH + DB_NAME;
    
            // Open the empty db as the output stream
            final OutputStream myOutput = new FileOutputStream(outFileName);
    
            // transfer bytes from the inputfile to the outputfile
            final byte[] buffer = new byte[1024];
            int length;
            while ((length = myInput.read(buffer)) > 0) {
                myOutput.write(buffer, 0, length);
            }
    
            // Close the streams
            myOutput.flush();
            myOutput.close();
            myInput.close();
    
        }
    
        public final SQLiteDatabase openDataBase() {
            // Open the database
            final String myPath = DB_PATH + DB_NAME;
            if (myDataBase != null && myDataBase.isOpen()) {
                myDataBase.close();
            }
            return myDataBase = SQLiteDatabase.openDatabase(myPath, null,
                    SQLiteDatabase.OPEN_READWRITE);
    
        }
    
        public final synchronized void closeDatabase() {
            if (myDataBase != null)
                myDataBase.close();
            super.close();
        }
    
        @Override
        public void onCreate(final SQLiteDatabase arg0) {
        }
    
        @Override
        public void onUpgrade(final SQLiteDatabase arg0, final int arg1,
                final int arg2) {
        }
    
    }
    

    in your code you do not put code to create database (copy db from data/data/databases/ddd.db) so.you have to get this type of error..

    please try this one.I hope its useful to you..