React Native - Połączenie z baza danych SQlite

Witam. Czy ktoś może mi powiedzieć jak w react-native dokonać połączenia z bazą danych sqlite?

W ramach nauki zainstalowałem sobie tą bibliotekę https://github.com/andpor/react-native-sqlite-storage

i próbuję stworzyć bazę danych oraz dokonać jakichś operacji, ale niestety stoję w miejscu z tym samym błędem.

Mój kod wygląda w ten sposób:

constructor() {
    super();
    this.state = {
        countryName:'',
        progress:''
    };
    this.startDB();

}
startDB(){

        SQLite.openDatabase({name: 'test.db', createFromLocation : "~example.db", location: 'Library'}).then((DB) => {
            db = DB;
            this.setState({
                progress:this.state.progress+"Database OPEN"
            });
        }).catch(error => {
           console.log(error);
           this.setState({
                progress:error
            });

        });
}

createDB(){

    db.executeSql('CREATE TABLE IF NOT EXISTS countrys( '
        + 'country_id INTEGER PRIMARY KEY NOT NULL, '
        + 'name VARCHAR(30) )');
}
adValue(){
    db.executeSql('INSERT INTO countrys (name) VALUES ("Polska")');
}

showValue(){
    db.executeSql('SELECT name FROM countrys').then((results) => {
        let len = results.rows.length;
        for (let i = 0; i < len; i++) {
            let row = results.rows.item(i);
            this.setState({
                countryName:this.state.countryName+row.name,
            });
        }

    }).catch((error) => {
        console.log(error);
    });
};

render() {
    return (
        <View>
            <Button
                color={'royalblue'}
                onPress={this.createDB}
                title="Create DB"
            />
            <Button
                color={'orange'}
                onPress={this.adValue}
                title="Add"
            />
            <Button
                color={'brown'}
                onPress={this.showValue}
                title="Show"
            />

            <Text>{this.state.countryName}</Text>
            <Text>{this.state.progress}</Text>
        </View>
    )
}

 
AppRegistry.registerComponent('SqliteComponent', () => SqliteComponent);

Po uruchomieniu aplikacji i kliknięciu w kolejne przyciski otrzymuję w konsoli takie komunikaty:

03-22 13:55:55.248 3386 3545 I ReactNativeJS: OPEN database: test
.db
03-22 13:55:55.249 3386 3545 I ReactNativeJS: SQLite.open({"name"
:"test.db","createFromLocation":"~example.db","location":"Library",
"dblocation":"libs","assetFilename":"~example.db"})
03-22 13:55:56.531 3386 3545 I ReactNativeJS: SQLite.backgroundEx
ecuteSqlBatch({"dbargs":{"dbname":"test.db"},"executes":[{"qid":111
1,"sql":"SELECT 1","params":[]},{"qid":1111,"sql":"CREATE TABLE IF
NOT EXISTS countrys( country_id INTEGER PRIMARY KEY NOT NULL, name
VARCHAR(30) ); ","params":[]}]})
03-22 13:56:08.196 3386 3545 I ReactNativeJS: SQLite.backgroundEx
ecuteSqlBatch({"dbargs":{"dbname":"test.db"},"executes":[{"qid":111
1,"sql":"SELECT 1","params":[]},{"qid":1111,"sql":"INSERT INTO coun
trys (name) VALUES ("Polska")","params":[]}]})
03-22 13:56:11.047 3386 3545 I ReactNativeJS: SQLite.backgroundEx
ecuteSqlBatch({"dbargs":{"dbname":"test.db"},"executes":[{"qid":111
1,"sql":"SELECT 1","params":[]},{"qid":1111,"sql":"SELECT name FROM
countrys","params":[]}]})
03-22 13:56:11.051 3386 3545 I ReactNativeJS: { [TypeError: undef
ined is not an object (evaluating 'results.rows.length')]
03-22 13:56:11.051 3386 3545 I ReactNativeJS: line: 76888,
03-22 13:56:11.051 3386 3545 I ReactNativeJS: column: 21,
03-22 13:56:11.051 3386 3545 I ReactNativeJS: sourceURL: 'http:
//10.0.2.2:8081/index.android.bundle?platform=android&dev=true&hot=
true&minify=false' }
03-22 13:57:06.646 3386 3545 I ReactNativeJS: 'Setting debug to:'
, true
03-22 13:57:06.646 3386 3545 I ReactNativeJS: Promise based runti
me ready
03-22 13:57:06.646 3386 3545 I ReactNativeJS: [React Transform HM
R] Patching SqliteComponent