[JaTochNietDan]

That's because pass is a variable, it needs to be a string.

Also I've taken the liberty of re-writing this for you in dcmd/sscanf, I think it's alot easier/cleaner.

pawn Код:

dcmd_login(playerid,params[])
{
  new password[20];
  if(sscanf(params,"s",password)) SendClientMessage(playerid,red,"Usage: /login <password>");
  else
  {
    new
        query[128],
        name[24];
    GetPlayerName(playerid,name,sizeof(name));
    mysql_escape_string(password,password);
    format(query,sizeof(query),"SELECT id FROM `players` WHERE Nombre = '%s' AND Password = '%s'",name,password);
    mysql_query(query);
    mysql_store_result();
    if(mysql_num_rows() > 0)
    {
      //And you can continue on here yourself ;)

You need dcmd and sscanf, which are popular functions all over the forums