onda ti ne treba distinct i mozes da stavis da ti pk bude user_datum ...
elem, mozes da ukrades malo .. zavisno od strukture samih podataka ovo moze da bude super brzo, samo onda kod tebe u aplikaciji iz group_concat izvadis samo prvi id posto te samo on zanima
Code:
select
*,
group_concat(dokument_id order by datum_dokumenta desc)
from
t1
group by
user_id;
primer:
Code:
mysql> select * from t1;
+-------------+-----------------+---------+
| dokument_id | datum_dokumenta | user_id |
+-------------+-----------------+---------+
| 1 | 1 | 1 |
| 2 | 2 | 1 |
| 3 | 3 | 1 |
| 10 | 10 | 1 |
| 4 | 4 | 1 |
| 2 | 2 | 2 |
| 3 | 3 | 2 |
| 10 | 4 | 2 |
| 20 | 6 | 2 |
| 50 | 5 | 2 |
+-------------+-----------------+---------+
10 rows in set (0.00 sec)
mysql> select *,group_concat(dokument_id order by datum_dokumenta desc) from t1 group by user_id;
+-------------+-----------------+---------+---------------------------------------------------------+
| dokument_id | datum_dokumenta | user_id | group_concat(dokument_id order by datum_dokumenta desc) |
+-------------+-----------------+---------+---------------------------------------------------------+
| 1 | 1 | 1 | 10,4,3,2,1 |
| 20 | 6 | 2 | 20,50,10,3,2 |
+-------------+-----------------+---------+---------------------------------------------------------+
2 rows in set (0.00 sec)
(obrati paznju da ti je u group concat id dokumenta sortiran po datumu i da ti polja dokument_id i datum_dokumenta ne vrede nicemu!!)