[Shaneisace]

pawn Code:

public OnPlayerConnect(playerid)
{
    mysql_format(gConnectionHandle,Query, "SELECT * FROM `users` WHERE `Username` = '%s'", GetName(playerid));
    mysql_function_query(gConnectionHandle, Query, false , "CheckPlayer", "d", playerid);
    return 1;
}

public OnPlayerDisconnect(playerid, reason)
{
    mysql_format(gConnectionHandle, Query, "UPDATE `users` SET `Money` = %d, `Score` = %d, `Admin` = %d, `Kills` = %d, `Deaths` = %d WHERE `Username` = '%s'",GetPlayerMoney(playerid),GetPlayerScore(playerid),PlayerInfo[playerid][pAdmin],PlayerInfo[playerid][pKills],PlayerInfo[playerid][pDeaths],GetName(playerid));
    mysql_function_query(gConnectionHandle, Query, false , "OnQueryFinish", "s", Query);
    return 1;
}

Don't use '' at UPDATE 'users' SET it must be UPDATE `users` SET and i have corrected your ' in the other places to `