Question

I have a table like this

id | user_id | code  | type | time
-----------------------------------
2    2         fdsa    r      1358300000
3    2         barf    r      1358311000
4    2         yack    r      1358311220
5    3         surf    r      1358311000
6    3         yooo    r      1358300000
7    4         poot    r      1358311220

I want to get the concatenated ‘code’ column for user 2 and user 3 for each matching time.

I want to receive a result set like this:

code     | time
-------------------------------
fdsayooo   1358300000
barfsurf   1358311000

Please note that there is no yackpoot code because the query was not looking for user 4.

Answer 1

You can use GROUP_CONCAT function. Try this:

SELECT GROUP_CONCAT(code SEPARATOR '') code, time 
FROM tbl 
WHERE user_id in (2, 3)
GROUP BY time
HAVING COUNT(time) = 2;

SQL FIDDLE DEMO