Question

I have these fields in MySQL:

rpt_id, rpt_entrydate, rpt_exitdate, rpt_date

and the values of these fields are as follows:

1, 2012-11-02, 2012-11-03, 2011-11-26
2, 2011-11-23, 2012-11-16, 2011-11-26
3, 2011-11-25, 2012-11-26, 2011-11-26
4, 2011-10-14, 2012-10-17, 2011-10-13
5, 2011-10-05, 2012-10-09, 2011-10-13
6, 2011-10-15, 2012-10-18, 2011-10-13

I want my result to look like this but it doesn’t work:

2011-11-25, 2012-11-26, 2011-11-23, 2012-11-16, 2012-11-02, 2012-11-03, 2011-11-26
2011-10-15, 2012-10-18, 2011-10-05, 2012-10-09, 2011-10-14, 2012-10-17, 2011-10-13

Answer 1

It appears you are attempting to string together all the dates associated with each rpt_date by group. You can do this with a GROUP_CONCAT() and a couple of CONCAT_WS() concatenations.

The inner CONCAT_WS() combines the pair of rpt_entrydate, rpt_exitdate into a comma-separated string, and the outer CONCAT_WS() pairs the GROUP_CONCAT() string with its rpt_date group.

SELECT
  CONCAT_WS(', ',
    GROUP_CONCAT(
      CONCAT_WS(', ', rpt_entrydate, rpt_exitdate)
    ),  rpt_date
  ) AS datestring
FROM yourtable
GROUP BY rpt_date

http://sqlfiddle.com/#!2/9a07a/5