我有一段Microsoft SQL代码，我正试图在MySQL(MariaDB 5.5.68)中使用。我尝试了一千种方法，但都无济于事。

SELECT t.title_id, t.title_name, p.pub_name,
    select a.au_fname + ' ' + a.au_lname from authors a
    join title_authors ta on a.au_id = ta.au_id
    where ta.au_order = 1 and ta.title_id = t.title_id)
    as author_1, isnull ((
    select a.au_fname + ' ' + a.au_lname from authors a
    join title_authors ta on a.au_id = ta.au id
    where ta.au_order = 2 and ta.title_id = t.title_id), '')
    as author_2, isnull((
    select a.au_fname + ' ' + a.au_lname from authors a
    join title_authors ta on a.au_id = ta.au_id
    where ta.au_order = 3 and ta.title_id = t.title_id), '')
    as author_3 from titles t
    join publishers p
    on p.pub_id = t.pub_id;

请救救我！

SELECT t.title_id, t.title_name, p.pub_name,
    (SELECT CONCAT(a.au_fname, ' ', a.au_lname)
        from authors a
        JOIN title_authors ta ON a.au_id = ta.au_id
        WHERE ta.au_order = 1 and ta.au_id = t.title_id) as author_1,
    ISNULL((
        SELECT CONCAT(a.au_fname, a.au_lname)
        from authors a
        JOIN title_authors ta ON a.au_id = ta.au_id
        WHERE ta.au_order = 2 and ta.au_id = t.title_id),'') as author_2,
    ISNULL((
        SELECT CONCAT(a.au_fname, a.au_lname)
        from authors a
        JOIN title_authors ta ON a.au_id = ta.au_id
        WHERE ta.au_order = 3 and ta.au_id = t.title_id),'') as author_3
FROM titles t
JOIN publishers p
ON p.pub_id = t.pub_id;

这将生成一个第一列为NULL、后两列为空的表。