Android SQLite Database Example Source Code: Creating a Simple Employee Database Application

In this tutorial, we will create a simple database application using SQLite on Android to store employee data. To achieve this, we will create a class that handles all the operations required to deal with the database such as creating the database, creating tables, inserting and deleting records.

The first step is to create a class that handles all the operations required to deal with the database. In our example, we will create a class called `DatabaseHandler` that has methods for creating the database, creating tables, inserting and deleting records.

Here's an example of how you can create the `DatabaseHandler` class:

```java

public class DatabaseHandler extends SQLiteOpenHelper {

private static final String DATABASE_NAME = 'employees.db';

private static final int DATABASE_VERSION = 1;

public DatabaseHandler(Context context) {

super(context, DATABASE_NAME, null, DATABASE_VERSION);

}

@Override

public void onCreate(SQLiteDatabase db) {

// Create the table for employees

db.execSQL('CREATE TABLE employees (_id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, department TEXT, email TEXT);');

}

@Override

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

// Drop the existing table and recreate it

db.execSQL('DROP TABLE IF EXISTS employees;');

onCreate(db);

}

```

In this class, we override the `onCreate` method to create the table for employees when the database is first created. We also override the `onUpgrade` method to drop the existing table and recreate it if the database version changes.

Now that we have the `DatabaseHandler` class, we can use it to interact with the database. For example, we can insert a new employee record using the following code:

```java

public void insertEmployee(String name, String department, String email) {

SQLiteDatabase db = this.getWritableDatabase();

ContentValues values = new ContentValues();

values.put('name', name);

values.put('department', department);

values.put('email', email);

db.insert('employees', null, values);

}

```

Similarly, we can delete an employee record using the following code:

```java

public void deleteEmployee(int id) {

SQLiteDatabase db = this.getWritableDatabase();

db.delete('employees', '_id=?', new String''{String.valueOf(id)});

}

```

In addition to inserting and deleting records, we also need to display employees and their relative departments. To achieve this, we can create a method that retrieves all the employee records from the database using the following code:

```java

public Cursor getAllEmployees() {

SQLiteDatabase db = this.getReadableDatabase();

return db.query('employees', new String''{'_id', 'name', 'department', 'email'}, null, null, null, null, null);

}

```

This method returns a cursor that contains all the employee records. We can then use this cursor to display the employees in a list view or grid view.

In conclusion, creating a simple database application using SQLite on Android involves creating a class that handles all the operations required to deal with the database such as creating the database, creating tables, inserting and deleting records. By following these steps and examples, you can create your own employee database application using SQLite on Android.

Android sqlite database example source code