Impossible to install WP

My problem is I can’t install wordpress on my server.

Everytime I upload the files to the root of my site, I go on the install page, and when I press “Install wordpress”, there is the same error :

Fatal error: mysql_num_fields(): supplied argument is not a valid MySQL result resource in /mnt/147/sda/3/0/gschmitz/wp-includes/wp-db.php on line 1134

I’ve been trying to reload the page in order to repair the database, but it doesn’t works..

So, I looked at the line 1134 of the concerned file, and here is the line :
while ( $i < @mysql_num_fields( $this->result ) ) {

I don’t understand php, so I hope you’ll figure out something for me.

Thanks !