SQL concatenated names get lost in rest of result - mysql

Question

I have a table containing zip, name and nb. If an entry has the same number (nb) as another one I wan to concatenate their names. So far it's working:
Here is SQL Fiddle with the following table and data:
CREATE TABLE `blubb` (
`zip` varchar(51) NOT NULL DEFAULT '',
`name` varchar(51) NOT NULL DEFAULT '',
`nb` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO blubb (zip, name, nb) VALUES ('1', 'aa', 1);
INSERT INTO blubb (zip, name, nb) VALUES ('2', 'bb', 2);
INSERT INTO blubb (zip, name, nb) VALUES ('3', 'cc', 3);
INSERT INTO blubb (zip, name, nb) VALUES ('4', 'dd', 2);
SELECT
zip,
name,
GROUP_CONCAT(name ORDER BY zip SEPARATOR '|') AS names
FROM blubb
GROUP BY nb
ORDER BY name ASC
Result:
+-----------------------+
| zip | name | names |
+-----------------------+
| 1 | aa | aa |
| 2 | bb | bb|dd |
| 3 | cc | cc |
+-----------------------+
But what I need is this:
+-----------------------+
| zip | name | names |
+-----------------------+
| 1 | aa | aa |
| 2 | bb | bb|dd |
| 3 | cc | cc |
| 4 | dd | dd|bb |
+-----------------------+
So if a number (nb) exists more then one time I don't want to lose it (which happend in my result). I want to select it and concatenate the names in alphabetic order. The name of the row itself should always be at first place in names followed by the other names in alphatbetic order.
Is this possible? How do I need to change my Query? I tried change the GROUP BY but nothing came closer to what I have.

Answer 1

You've been bitten by MySQL's notorious nonstandard extension to GROUP BY. A standard server would reject your query.
What you need is a subquery to get the list of names for each value of nb. Like so.
SELECT nb,
GROUP_CONCAT(name ORDER BY zip SEPARATOR '|') AS names
FROM blubb
GROUP BY nb
Then you join that to your detail table. Like so. (http://sqlfiddle.com/#!9/efbef6/9/0)
SELECT a.zip, a.name, b.names
FROM blubb a
JOIN (
SELECT nb,
GROUP_CONCAT(name ORDER BY zip SEPARATOR '|') AS names
FROM blubb
GROUP BY nb
) b ON a.nb = b.nb
ORDER BY a.zip

Answer 2

Try something like this:
SELECT q.zip, q.name,
( SELECT GROUP_CONCAT(w.name ORDER BY w.zip SEPARATOR '|')
FROM blubb AS w
WHERE w.nb = q.nb
ORDER BY w.name <> q.name, w.name ) AS names
FROM blubb AS q
ORDER BY q.name ASC
Edit
Added ordering, that the actual value would be the first. However, if there are multiple rows with the same value, all of them would go to the beginning of the list...

Answer 3

I would do like this:
select b.zip, b.name, g.names
from blubb b
inner join (SELECT
nb,
GROUP_CONCAT(name ORDER BY zip SEPARATOR '|') AS names
FROM blubb
GROUP BY nb) g on b.nb = g.nb
ORDER BY name ASC

Answer 4

Thanks to O. Jones answer it was easy to do some string manipulation to get the desired output at the end. This query is was I was looking for, maybe it's helpful to someone else:
SQL Fiddle
SELECT
a.zip,
a.name,
REPLACE(
CONCAT( a.name, '|', b.names ),
CONCAT('|', a.name),
''
) AS names
FROM blubb a
JOIN (
SELECT
nb,
GROUP_CONCAT(name ORDER BY name ASC SEPARATOR '|') AS names
FROM blubb
GROUP BY nb
) b ON a.nb = b.nb
ORDER BY a.zip
and the table with data:
CREATE TABLE `blubb` (
`zip` varchar(51) NOT NULL DEFAULT '',
`name` varchar(51) NOT NULL DEFAULT '',
`nb` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO blubb (zip, name, nb) VALUES ('1', 'aa', 1);
INSERT INTO blubb (zip, name, nb) VALUES ('2', 'bb', 2);
INSERT INTO blubb (zip, name, nb) VALUES ('3', 'cc', 3);
INSERT INTO blubb (zip, name, nb) VALUES ('4', 'dd', 2);
INSERT INTO blubb (zip, name, nb) VALUES ('5', 'ab', 2);
INSERT INTO blubb (zip, name, nb) VALUES ('5', 'cb', 2);
INSERT INTO blubb (zip, name, nb) VALUES ('6', 'ca', 2);
here is SQL Fiddle with alphabetical order on the resulting names