Android Sqlite Performance

Question

I have been doing some experiments to measure sqlite performance on android. I was disappointed a little bit with the results. What i did was inserting 10.000 queries to table and it took 130-140 seconds but with these conditions;

1. Samsung galaxy s3 in power saving mode

2. Inserted data(or class)has 3 strings and one float(real for sqlite)

3. Insert event is being done in asynctask.

4. In asynctask, i am showing a progress dialog with passed timer text in it (System.currentTimeMillis - seconds etc blala)

class AddStudentsTask extends AsyncTask<Void,Integer,Void>
{
    ProgressDialog prgDialog;
    int max = 10000;
    Student s;
    long seconds = System.currentTimeMillis();


    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        prgDialog = new ProgressDialog(MainActivity.this);
        prgDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
        prgDialog.setMessage(seconds+"");
        prgDialog.setMax(max);
        prgDialog.setCancelable(false);
        prgDialog.show();

    }

    @Override
    protected void onProgressUpdate(Integer... values) {
        super.onProgressUpdate();
        prgDialog.setProgress(values[0]);
        sList.add(s);
        String s = (System.currentTimeMillis()-seconds)/100+"";
        if(s.length()>2)
            s = s.substring(0,s.length()-1) + "." + s.charAt(s.length()-1);
        else if(s.length() == 2)
            s = s.charAt(0) + "." + s.charAt(1);
        prgDialog.setMessage(s + " seconds passed.");

    }

    @Override
    protected Void doInBackground(Void... voids) {

        for(int a = 0;a< max; a++ )
        {
            Random r = new Random();
            s = new Student();

            s.setGpa(r.nextFloat()*4);
            s.setLastName("asdasd");
            s.setFirstName("Oh My God");
            s.setAddress("1sadasd");
            s.setId(sda.insert(s));
            publishProgress(a);
        }

        return null;
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        super.onPostExecute(aVoid);
        prgDialog.dismiss();
        sa.notifyDataSetChanged();
    }
}

5. I am using contentValues with insertOrThrow method in helperdb class. THIS IS OLD SLOW CODE

public long insert(Student s)
{
    SQLiteDatabase db = sh.getWritableDatabase();
    ContentValues cv = new ContentValues();
    cv.put(StudentHelper.FIRSTNAME,s.getFirstName());
    cv.put(StudentHelper.LASTNAME,s.getLastName());
    cv.put(StudentHelper.ADDRESS,s.getAddress());
    cv.put(StudentHelper.GPA,s.getGpa());
    s.setId(db.insertOrThrow(StudentHelper.TABLE_NAME, null, cv));
    return s.getId();
}

6. This task is done in onCreate method of activity.

So what am i doing wrong here or expecting too much from it? Are these results ok or bad?

What can i do to improve my code?

EDIT

So i changed my insert code to this and it reduced to 4.5 seconds!!!

public ArrayList<Long> insertMany(ArrayList<Student> stus)
{
    ArrayList<Long> ids = new ArrayList();
    String sql = "INSERT INTO "+StudentHelper.TABLE_NAME+"" +
            "("+StudentHelper.FIRSTNAME+","+StudentHelper.LASTNAME+"," +
            " "+StudentHelper.GPA+") values(?,?,?)";
    SQLiteDatabase db = sh.getWritableDatabase();
    db.beginTransaction();

    for(Student s:stus) {
        SQLiteStatement stmt = db.compileStatement(sql);

        stmt.bindString(1, s.getFirstName());
        stmt.bindString(2, s.getLastName());
        stmt.bindDouble(3, s.getGpa());

        s.setId(stmt.executeInsert());
        ids.add(s.getId());
        stmt.clearBindings();
    }

    db.setTransactionSuccessful();
    db.endTransaction();

    return ids;
}

Answer 1

Use SQLite transaction for speed up

Use BEGIN TRANSACTION & END TRANSACTION for SQLite Optimization

Each SQL statement is enclosed in a new transaction block by SQLite runtime, by default. Sowhen you perform a basic DB operation such as INSERT, a transaction block will be created and wrapped around it.

Letting SQLite runtime manage the transaction for you is advisable only if your routine performs only one DB operation on a data set. However, if you are doing numerous DB operations (say INSERT inside for loop), this becomes very expensive, since it requires reopening, writing to, and closing the journal file for each statement. You may refer

1. Android SQLite database: slow insertion

2. http://www.androidcode.ninja/android-sqlite-transaction-tutorial/

3. http://www.techrepublic.com/blog/software-engineer/turbocharge-your-sqlite-inserts-on-android/

4. http://www.android-app-market.com/sqlite-optimization-in-android-programming-sqlite-optimization-in-android-apps.html

Answer 2

You can use SQL transactions in Android like this. It's better to insert multiple rows into the database in larger batches then making single commit (write into SQLlite datafile which is very slow) for every inserted row.

public void insert(List<Student> students)
{
    SQLiteDatabase db = sh.getWritableDatabase();
    ContentValues cv = new ContentValues();

    db.beginTransaction();

    try {
        for (Student s : students) {
            cv.put(StudentHelper.FIRSTNAME,s.getFirstName());
            cv.put(StudentHelper.LASTNAME,s.getLastName());
            cv.put(StudentHelper.ADDRESS,s.getAddress());
            cv.put(StudentHelper.GPA,s.getGpa());

            db.insertOrThrow(StudentHelper.TABLE_NAME, null, cv)
        }
        db.setTransactionSuccessful();
    } finally {
        db.endTransaction();
    }
}