Question

In mysql db table I have projects with one to many relation with domain table like

projects

----------------
proId | domainId
----------------
  1        1
  1        2
  2        1
  3        3

domain

---------------------
domainId | domainName
---------------------
    1        Web
    2        Mobile
    3        iPhone

I query

SELECT p.*, d.* FROM projects p LEFT JOIN domain d ON p.domainId = d.domainId

which results

result

-----------------------------
proId | domainId | domainName
-----------------------------
  1       1          Web
  1       2          Mobile
  2       1          Web
  3       3          iPhone

but is it possible to show all domains as single value with concatenation some thing like

-----------------------------
proId | domainId | domainName
-----------------------------
  1       1, 2    Web, Mobile
  2       1       Web
  3       3       iPhone

Answer 1

probably you are looking for GROUP_CONCAT function.

SELECT  a.proID,
        GROUP_CONCAT(b.domainID) domainId,
        GROUP_CONCAT(b.domainName) domainName
FROM    projects a
        LEFT JOIN domain b
            ON a.domainID = b.domainID
GROUP BY a.proID

SQLFiddle Demo