How to limit values when using distinct

Question

PHP

  SELECT DISTINCT bk.title AS Title, bk.year AS Year, aut.authorname AS Author, cat.category AS Category
         FROM book bk 

         JOIN book_category          


        

Answer 1

I think you might want to look into subquery-ing with the group_concat() so please give this a try:

group_concat() will merge the results of the sub-query and provide you with one string of authors separated by a comma-space like this author1, author2, author3

SELECT
    DISTINCT bk.title AS Title,
    bk.year AS 'Year',
    (
        SELECT
            group_concat(aut.authorname, ', ')
        FROM
            authors aut
            LEFT OUTER JOIN
                books_authors bk_aut
                ON
                    aut.id=bk_aut.author_id
        WHERE
            bk_aut.book_id = bk.book_id
    ) AS Author
FROM
    book bk
ORDER BY
    bk.title ASC