DatabaseHelper

package com.example.tugassqlfirebase;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import androidx.annotation.Nullable;

public class DatabaseHelper extends SQLiteOpenHelper {

    Context context;
    static final String DATABASE_NAME = "User.db";
    static final int DATABASE_VERSION = 1;

    static final String TABLE_NAME = "user";
    static final String COLUMN_ID = "_id";
    static final String COLUMN_NAME = "fullname";
    static final String COLUMN_USERNAME = "username";
    static final String COLUMN_AGE = "age";
    static final String COLUMN_STATUS = "status";

    DatabaseHelper(@Nullable Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        this.context = context;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String query = " CREATE TABLE " + TABLE_NAME +
                " (" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                COLUMN_NAME + " TEXT, " +
                COLUMN_USERNAME + " TEXT, " +
                COLUMN_AGE + " TEXT, " +
                COLUMN_STATUS + " TEXT); ";
        db.execSQL(query);

        String insert = " INSERT INTO " + TABLE_NAME + " VALUES ( 1, 'Herza Avicena', 'Apicendol',  '21', 'Available' )";

        db.execSQL(insert);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int i, int i1) {
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        onCreate(db);
    }

    void updateData (String id, String fullname, String username, String age, String status) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues cv = new ContentValues();
        cv.put(COLUMN_NAME, fullname);
        cv.put(COLUMN_USERNAME, username);
        cv.put(COLUMN_AGE, age);
        cv.put(COLUMN_STATUS, status);

        db.update("user", cv, "_id = ?", new String[]{"1"});
    }

    Cursor readData () {
        SQLiteDatabase DB = this.getWritableDatabase();
        Cursor cursor = DB.rawQuery("SELECT * FROM user", null);
        return cursor;
    }
}