运用SQLite存储数据

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //每个程序都与自己的数据库  默认情况下是各自互不干扰
        //1。创建一个数据库  并且打开
        SQLiteDatabase db=openOrCreateDatabase("user.db",MODE_PRIVATE,null);//名字，权限
        db.execSQL("create table if not exists usertb(_id integer primary key autoincrement,name text not null,age interger not null,sex text not null)");
        db.execSQL("insert into usertb(name,sex,age)values('张三','女',18)");
        db.execSQL("insert into usertb(name,sex,age)values('李四','女',19)");
        db.execSQL("insert into usertb(name,sex,age)values('王五','男',20)");

        Cursor c=db.rawQuery("select *from usertb",null);
        if(c!=null)
        {
            while(c.moveToNext())
            {
                Log.i("info","_id:"+c.getInt(c.getColumnIndex("_id")));
                Log.i("info","name:"+c.getString(c.getColumnIndex("name")));
                Log.i("info","sex:"+c.getString(c.getColumnIndex("sex")));
                Log.i("info","age:"+c.getInt(c.getColumnIndex("age")));
                Log.i("info","!!!!!!!!!!!!!!!!!!!!!!!!!");
            }
            c.close();
        }
        db.close();
    }
}