[Konstantinos]

That's because you get the data from the row 0 only. You should use a loop for that:

pawn Код:

for (new i; i != num_rows; i++)
{
    cache_get_row(i, 0, temp_username); // only 1 field so no need to let it search for the fieldid
    iEcho(temp_username);
}

EDIT:
Also escape your strings to avoid from being victim of SQL Injection and also selecting only the field you want and not all the data.

pawn Код:

mysql_format(dbhandle,query,sizeof(query),"SELECT username FROM user WHERE regip ='%e'",temp_ip);