[Grim_]

Something like this: (Copied directly from rAdmin script)

pawn Код:

public MySQLCheckUserExistance(playerid)
{
    GetPlayerName(playerid, PlayerName, sizeof(PlayerName));

    format(query, sizeof(query), "SELECT `reg_id` FROM `users` WHERE `name` = '%s'", PlayerName);
    samp_mysql_query(query);
    samp_mysql_store_result();

    if(samp_mysql_num_rows() == 0)
    {
        return 0;
    }
    else
    {
      return 1;
    }
}

Usage:

pawn Код:

if(MySQLCheckUserExistance(playerid))
{
  //User is in the database (exists)
}