Create Database class

Here is an example to create database using SqliteHelper class in android.
We are creating a database with the name "detail" and having 4 columns as :-Key, Name, City and Age.

public class CreateDatabase {
    public DatabaseHelper mDbHelper;
    public SQLiteDatabase mDb;  
    public static final String DATABASE_NAME= "Detail_database";    // Internal Database
//    public static final String DATABASE_NAME= Environment.getExternalStorageDirectory()+File.separator+"Detail_database.sqlite";      //External Database
    public static final String TAG = "tag";
    public static final int DATABASE_VERSION = 1;

    public static final String Id = "id";

    // Definition for Detail Table
    public static final String Key = "key";
    public static final String Name = "name";
    public static final String City = "city";
    public static final String Age = "age";
    public static final String DATABASE_TABLE_DETAIL = "DETAIL";

    /** * Database creation sql statement */

    //Detail Table creation
    private static final String DATABASE_CREATE_DETAIL = "CREATE TABLE IF NOT EXISTS "
            + DATABASE_TABLE_DETAIL + " (Key text PRIMARY KEY, "+" Name text, "+" City text" +
            ", "+" Age text)";


    private final Context mCtx;

    private static class DatabaseHelper extends SQLiteOpenHelper {
        DatabaseHelper(Context context) { 
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        /**
         * Creating Tables
         */

        @Override
        public void onCreate(SQLiteDatabase db) {
            try{
                db.execSQL(DATABASE_CREATE_DETAIL);

                Log.i(TAG, "DATABASE IS CREATING.............");
            }
            catch(SQLException e){

            }
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

        }
    }
    public CreateDatabase(Context ctx) {

        this.mCtx = ctx;
    }

    public void DeleteDatabase(String table)
    {
        mDb.delete(table, null, null);   
    }

    public CreateDatabase open() throws SQLException {

        //  Log.i(TAG, "OPening DataBase Connection....");
        mDbHelper = new DatabaseHelper(mCtx);
        mDb = mDbHelper.getWritableDatabase();
        return this;
    }

    public SQLiteDatabase openDB() throws SQLException{
        //  Log.i(TAG, "OPening DataBase Connection....");
        mDbHelper = new DatabaseHelper(mCtx);
        mDb = mDbHelper.getWritableDatabase();
        return mDb;
    }
    public void close() {
        //  Log.i(TAG, "Closing DataBase Connection....");
        mDbHelper.close();

    }

    // Inserting record values for Detail
    public long createElementsDetail(String key, String name, String city, String age) {
        //  Log.i(TAG, "Inserting Detail   ...");

        ContentValues initialValues = new ContentValues();
        initialValues.put(Key, key);
        initialValues.put(Name, name);
        initialValues.put(City, city);
        initialValues.put(Age, age);

        return mDb.insert(DATABASE_TABLE_DETAIL, null, initialValues);
    }

    /**
     * Cursor for Detail
     * @return
     * @throws android.database.SQLException
     */
    public Cursor fetchDetail() throws SQLException{
        Cursor mCursor = mDb.query(DATABASE_TABLE_DETAIL, new String[] {Key, Name, City, Age},null,null,null,null,null);
        if (mCursor != null) {
            mCursor.moveToFirst();
        }
        return mCursor;
    }
}

MainActivity

Here is the main activity class to call the create database class and to fill data in the columns of the table.

public class MainActivity extends Activity {
    CreateDatabase db;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        db = new CreateDatabase(MainActivity.this);
        db.open();
        db.createElementsDetail("1", "Ankit", "Dehradun", "12");
        db.close();
    }
}

Manifest Permissions
We need external storage permission if we make database on external storage.

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE">
    </uses-permission>