Sql correct syntax for raw query in laravel - sql

Question

I have tested this query in mysql and it works.
it doesn't work in mine controller. Can anyone correct it please?
$albi = DB::table(DB::raw("(SELECT
albi.id,
albi.CoverAlbo,
albi.Nazione,
albi.Editore,
albi.NomeCollanaUfficiale,
albi.AnnoPubblicazione
FROM albi AS a LEFT JOIN albi_user AS au ON a.id = au.albi_id
AND au.user_id = $user_id
WHERE au.albi_id IS NULL)"));
this is the error:
SQLSTATE[42000]: Syntax error or access violation: 1248 Every derived table must have its own alias
please help me!!!

Answer 1

This is because you're using DB::table() and then placing a raw query inside it (creating a sub query) and then not giving it an alias.
To get your above code to work you should just need to change the last line to something like:
WHERE au.albi_id IS NULL) as t1")); //notice the "t1" alias
Or you could DB::select():
$albi = DB::select("SELECT
a.id,
a.CoverAlbo,
a.Nazione,
a.Editore,
a.NomeCollanaUfficiale,
a.AnnoPubblicazione
FROM albi AS a LEFT JOIN albi_user AS au ON a.id = au.albi_id
AND au.user_id = $user_id
WHERE au.albi_id IS NULL");
Please note this is not the same select() as DB::table()->select()
Or you could just use the the Query Builder:
$albi = DB::table('albi')
->select('id', 'CoverAlbo', 'Nazione', 'Editore', 'NomeCollanaUfficiale', 'AnnoPubblicazione')
->leftJoin('albi_user', 'albi.id', 'albi_user.alibi_id')
->where('albi_user.user_id', $user_id)
->whereNull('albi_user.albi_id')
->get();
Hope this helps!

Answer 2

You should use alias instead of table name. So try this:
$albi = DB::table(DB::raw("(SELECT
a.id,
a.CoverAlbo,
a.Nazione,
a.Editore,
a.NomeCollanaUfficiale,
a.AnnoPubblicazione
FROM albi AS a LEFT JOIN albi_user AS au ON a.id = au.albi_id
AND au.user_id = $user_id
WHERE au.albi_id IS NULL)"));