MySQL-多个内部联接和concat

Question

I have a database, here are the tables I need:

• special_issues
• journals
• journal_editors

The structure is like described here:

• I have special issues, each special issue belongs to a journal, so in the table special_issue, I have the journal_id
• For each journal, I have editors (one or more). This info can be obtained from the journal_editors table by matching the editors for the specific journal_id.

What I would like to get is for each special issue, the journal editors of the journal this special issue belongs.

For that, I would like to concat the id's, so at the end I will have something like this:

special issue    editors
     si1         1,5,10
     si2         14,25,5 

Etc...

I tryied that:

SELECT si.name, CONCAT(users.firstname,' ', users.lastname) AS journal_editors
FROM `special_issues` si
INNER JOIN journal_editors jeds ON si.journal_id = journal_id
WHERE si.journal_id =1 GROUP BY si.name"

Thank you very much in advance.

Answer 1

SELECT si.name, GROUP_CONCAT(users.firstname,' ', users.lastname) AS journal_editors 
FROM special_issues si 
INNER JOIN journal_editors jeds ON si.journal_id = journal_id 
WHERE si.journal_id =1 
GROUP BY si.name

Manual entry .

Answer 2

SELECT si.name, GROUP_CONCAT(users.firstname,' ', users.lastname) AS journal_editors
  FROM `special_issues` si
 INNER 
  JOIN journal_editors jeds ON si.journal_id = jeds.journal_id
 WHERE si.journal_id =1 
 GROUP BY si.name