在SQL中按组获取特定条目

Question

I've a database who contain some datas in that form:

icon(name, size, tag)
(myicon.png, 16, 'twitter')
(myicon.png, 32, 'twitter')
(myicon.png, 128, 'twitter')
(myicon.png, 256, 'twitter')
(anothericon.png, 32, 'facebook')
(anothericon.png, 128, 'facebook')
(anothericon.png, 256, 'facebook')

So as you see it, the name field is not uniq I can have multiple icons with the same name and they are separated with the size field. Now in PHP I have a query that get ONE icon set, for example :

mysql_query("SELECT * FROM icon WHERE tag='".$tag."' ORDER BY size LIMIT 0, 10");

With this example if $tag contain 'twitter' it will show ONLY the first SQL data entry with the tag 'twitter', so it will be :

(myicon.png, 16, 'twitter')

This is what I want, but I would prefer the '128' size by default. Is this possible to tell SQL to send me only the 128 size when existing and if not another size ?

Thanks !

Answer 1

ORDER BY size DESC?