mysql sortirowka

polojenieto e slednoto:

imam tablica, koqto izglejda po sledniq nachin:

------------------------------------------------
| id | cat | subcat | URL |
------------------------------------------------
| 0 | cat1 | subcat1 |[линк] |
------------------------------------------------
| 1 | cat1 | subcat1 |[линк] |
------------------------------------------------
| 2 | cat1 | subcat1 |[линк] |
------------------------------------------------
| 3 | cat1 | subcat2 |[линк] |
+-----------------------------------------------
natam prodyljawa do catN

wyprosa mi e ako w poleto 'cat' ima 300 podkategorii, a pyk te sami po sebe si imat po 600 linka na kategoriq kak da list-na subcategoriite bez da se powtarqt , zashtoto nqma da e udachno da gi pisha na ryka, a pyk ako izpolzwam neshto ot sorta na :

while($arr=mysql_fetch_array("select * from tablica where cat='cat1'") {

echo $row[subcat];

wryshta

subcat1
subcat1
subcat1
subcat1
subcat2
subcat2
subcat2

Shte byda blagodaren, ako nqkoi mi pomogne da izbegna towa powtorenie, taka che rezultatyt da izglejda po sledniq nachin:

subcat1
subcat2
subcat3.....

Predwaritelno blagodarq

Това е въпрос за клуб "Бази данни", ама все пак:


select distinct subcat from tablica where cat='cat1'