SQL performance ( MySQL ) -

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i have tabel,

create table `forum_rank` (   `id` int(11) not null auto_increment,   `user_id` int(11) not null default '0',   `rank` int(11) not null default '0',   `forum_id` int(11) not null default '0',   primary key (`id`) ) engine=myisam auto_increment=2 default charset=latin1;

now ask perfome best, * or alle felt 2 eg.

select * form forum_rank;

or 

select id, user_id, rank, forum_id forum_rank;

you should explicitly specify columns. otherwise database engine first have find out table's columns (resolve * operator) , after perform actual query.


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