Cannot execute GROUP_CONCAT - mysql

Question

I'm trying to return as GROUP_CONCAT 5 matches associated to the joined records, I tried to setup the query in the following way:
$sql = $this->db->prepare("SELECT l.*,
t.name as team_name,
r.name AS rank_name,
r.color AS rank_color,
GROUP_CONCAT(DISTINCT m.* LIMIT 5, ORDER BY m.id) AS last_five_matches,
FROM league_ranking l
LEFT JOIN team t ON l.team_id = t.id
LEFT JOIN competition_ranks r ON l.rank = r.id
LEFT JOIN `match` m ON m.home_team_id = l.team_id OR m.away_team_id = l.team_id
WHERE l.round_id = :round_id AND m.status = 5");
as you can see I want return 5 matches which have the status = 5.
The problem's that I get:
SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '* LIMIT 5, ORDER BY m.id) AS last_five_matches,
FROM league_ranking l
I don't understand where is the problem on the GROUP_CONCAT, notice that if I remove GROUP_CONCAT the query working, any help?
UPDATE
this is the query edited:
"SELECT l.*,
t.name as team_name,
r.name AS rank_name,
r.color AS rank_color,
GROUP_CONCAT(DISTINCT m.id ORDER BY m.id) AS last_five_matches
FROM league_ranking l
LEFT JOIN team t ON l.team_id = t.id
LEFT JOIN competition_ranks r ON l.rank = r.id
LEFT JOIN `match` m ON m.home_team_id = l.team_id OR m.away_team_id = l.team_id
WHERE l.round_id = :round_id AND m.status = 5
GROUP BY team_name"
and I get:
Syntax error or access violation: 1055 Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'swp.l.position' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

Answer 1

I believe you want:
SELECT t.name as team_name, r.name AS rank_name, r.color AS rank_color,
SUBSTRING_INDEX(GROUP_CONCAT(DISTINCT m.id ORDER BY m.id), ',', 5) AS last_five_matches
FROM team t LEFT JOIN
league_ranking l
ON l.team_id = t.id LEFT JOIN
competition_ranks r
ON l.rank = r.id LEFT JOIN
`match` m
ON m.home_team_id = l.team_id OR m.away_team_id = l.team_id
WHERE l.round_id = :round_id AND m.status = 5
GROUP BY t.name, r.name, r.color;
Notes:
The GROUP BY keys exactly match the unaggregated columns in the SELECT.
I removed the l.*. It doesn't make sense in the GROUP BY query.
GROUP_CONCAT() doesn't support LIMIT. Sounds like a good idea, but it doesn't exist. Instead, form the list then take the first 5 elements.
I change the JOIN order to start with team. You seem to want one row per team, so that should be the first table in the FROM.

Answer 2

GROUP_CONTACT is an Aggregation Operation which you need to have a GROUP BY clause describe under which values you are aggregating the records
SELECT l.*,
t.name as team_name,
r.name AS rank_name,
r.color AS rank_color,
GROUP_CONCAT(DISTINCT m.<column_name> LIMIT 5, ORDER BY m.id) AS last_five_matches,
FROM league_ranking l
LEFT JOIN team t ON l.team_id = t.id
LEFT JOIN competition_ranks r ON l.rank = r.id
LEFT JOIN `match` m ON m.home_team_id = l.team_id OR m.away_team_id = l.team_id
WHERE l.round_id = :round_id AND m.status = 5
GROUP BY team_name, rank_name, rank_color

Answer 3

According to the mysql documentation you can't use LIMIT statement with GROUP_CONCAT(). Try this one :
.. GROUP_CONCAT(DISTINCT m.id, ORDER BY m.id) AS last_five_matches ..