multiple relationship using dapper code example

Example: multiple relationship using dapper

using (var connection = new SQLiteConnection(connString)){    var sql = @"select p.postid, headline, firstname, lastname, t.tagid, tagname                from posts p                 inner join authors a on p.authorid = a.authorid                inner join posttags pt on pt.postid = p.postid                inner join tags t on t.tagid = pt.tagid";    var posts = await connection.QueryAsync<Post, Author, Tag, Post>(sql, (post, author, tag) => {        post.Author = author;        post.Tags.Add(tag);        return post;    }, splitOn: "firstname, tagid");    var result = posts.GroupBy(p => p.PostId).Select(g =>    {        var groupedPost = g.First();        groupedPost.Tags = g.Select(p => p.Tags.Single()).ToList();        return groupedPost;    });    foreach(var post in result)    {        Console.Write($"{post.Headline}: ");        foreach(var tag in post.Tags)        {            Console.Write($" {tag.TagName} ");        }        Console.Write($" by {post.Author.FirstName} {post.Author.LastName} {Environment.NewLine}");    }}