1、创建一个继承于SQLiteOpenHelper的子类

public class SqliteHelper extends SQLiteOpenHelper {
    private static SqliteHelper instance;
    public static synchronized SqliteHelper getInstance(Context context) {
        if (instance == null) {
            instance = new SqliteHelper(context, "myword.db", null, 1);
        }
        return instance;
    }

    private SqliteHelper(@Nullable Context context, @Nullable String name, @Nullable SQLiteDatabase.CursorFactory factory, int version) {
        super(context, name, factory, version);
    }

    //数据库初始化表
    @Override
    public void onCreate(SQLiteDatabase db) {
        String sql = "create table words(_id integer primary key autoincrement,word text unique,level integer,type text)";
        db.execSQL(sql);
    }

    //数据库升级
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

2、初始化数据库及